While there is significant controversy about the use of mobile phones and whether they will cause or contribute to particular diseases, there is no doubt that they have the potential to cause harm. A serious problem lies with our inability to measure the relationship between our exposure to radiofrequency radiation and resulting disease. Just as difficult is separating out the roles of vested interests. While the weight of evidence from industry and government studies suggests that there is little, if any, problem, the majority of evidence from independent studies indicates that there are very serious issues that require careful consideration. However, once technology is rolled out it is almost impossible to roll it back.
The problem with mobile phones is that they emit radio frequency from the base station antennas, producing low but continuous exposure to entire communities and to the mobile phone or handset, which produces intense, intermittent exposure to the head of the user. Mobile telephones operate on sending and receiving frequencies in the approximate range of 825 MHz to 915 MHz, although with the continued expansion of this technology, the range of frequencies to which users are potentially exposed may be broadened to 450 MHz to 2500 MHz. The antenna of the phone radiates power equally in all directions at peak levels of 1-2 W when the phone is operating. Also emitted from the phone is a low-frequency magnetic field, associated with surges in electric current from the battery, generally in the range of 0.125 W – 0.25 W.
The amount of this radiation that is actually absorbed by the user varies according to the amount of power emitted from particular phones. The amount of power depends on design factors such as make, model and type of aerial as well as individual use of the device—including the proximity of the phone to the ear or skull, the orientation of the phone and the use of “hands-free” phone kits. The proximity of the phone to the user’s head has been found to have the most significant relationship between mobile phone use and the amount of microwave and radiofrequency radiation the head absorbs.
From the phone being in contact with the head, the amount of power that is absorbed decreases exponentially as the phone is moved farther away from the ear. That is, exposure to the radiation decreases a lot with just a small move of the phone away from the head. The amount of power that is absorbed can decrease by as much as 25 percent with the phone being placed one centimetre from the head when in use. “Hands-free” kits are also a practicable means of reducing exposure to radiation by two orders of magnitude, due to the increased distance of the phone to the sensitive tissues of the human body. Similarly, the use of the speakerphone held away from the head can also dramatically reduce exposure.
Health effects
The effects of non-ionising radiation from mobile phones can be broadly categorised into thermally (heat) induced and non-thermally induced biological effects. Non thermal effects of mobile phones include headache, memory problems, increase in frequency of seizures in children, decrease in duration of deep sleep and inhibition of secretion of melatonin.
Typical effects that have been noted in human studies include radiofrequency sickness, electroencephalographic changes, cell proliferation, blood pressure changes and blood-brain barrier leakages. Also confirmed have been transient, but significant, modifications in dermal or cutaneous blood flow as a result of standard operation of mobile phones. There are many less severe effects linked to mobile phone use; these include headache, sore muscles (radiating from the ear to the temple and through the shoulders) and sleep disturbances.
There is also growing concern about the potential contribution of mobile phones to brain cancer, leukaemia and acoustic neuroma (a particular tumour) in the head and neck. Few epidemiological studies have managed to confirm a solid link between mobile phone usage and tumour formation; making such links is extremely complicated due to issues such as the latency period between exposure and onset of symptoms. It may also be due to the strong industry bias in research. However, several population and surrogate studies have produced alarming results. In a national US study, a significantly increased incidence of neuroepithelial tumours was found to be consistent with mobile phone usage. This was indicated by increased DNA strand breaks and chromosomal aberrations, which promote the development of tumours. Other studies have reported similar findings, noting changes in the development of enzymes associated with carcinogenesis after exposure to radiofrequency radiation. This suggests that the influence of radiofrequency and microwave radiation is more localised to the source of the energy and perhaps aided by the ability of radiofrequency radiation to interfere with the blood-brain barrier. This is supported in surrogate studies on animals, which showed influences on immuno-reactivity and neurotransmitters within the brain. My take is that mobile phones contribute to brain tumours and exposure should be limited as much as possible.
The impact of radiofrequency on male reproductive organs is also an area of increasing distress due to the known interference of radiofrequency and microwave radiation on the testes. A recent study found that electromagnetic radiation from mobile phones interferes with human sperm motility, the ability of the sperm to progress through the reproductive tract. This is of prime concern as this interference may lead to structural and behavioural changes in the male germ cell that may not be apparent until later in life. In a study of laboratory animals exposed to low-energy radiofrequency radiation (that is, from a mobile phone), the exposure group experienced higher percentages of non-progressive or no-motility sperm. This could generate problems in the future for many, given the young age at which individuals start to use mobile phones.
While there are many concerns about the use of mobile phones, most governments are locked into the continued and expanded use of these devices. Authorities around the world are vague on the subject of mobile phones, mainly because of economic reasons. Despite this, the World Health Organization recommends that one limit time on mobile phones and use hands free devices whenever possible. The WHO also advises to use a “land line” phone when available, limit the duration of mobile phone conversations, fully extend the phone’s antenna where possible (i.e., if the phone has an external antenna) and use one’s mobile phone in an open area so the phone transmits at a lower power level.
The controversy about the health effects of mobile phones is illustrated by a 2001 report from the Independent Expert Group on Mobile Phones, which stated that children under the age of 16 should be discouraged from using these devices. The reason for this recommendation is the potential for children to absorb more energy from radiation as a result of their relatively smaller head sizes, thinner skulls and higher tissue conductivity. The age recommendation was lowered to 10 years in 2004. This was due to pressure from the mobile phone companies, especially given that teenagers are probably the biggest users of mobile phones and these companies could have lost a significant portion of a growing, captive market.
Mobile phone towers are another big potential problem. They emit microwave signals in a relatively wide beam. These emissions have intensities that are quite high at close range to the antenna but which drop in intensity with distance. By any measure, the level of the signal is relatively low on the ground but residents nearby are exposed to these emissions 24 hours a day. No one knows the long-term effects of this type of exposure or the range of susceptibility.
Wednesday, June 1, 2011
Monday, May 30, 2011
The costs of workplace stress
Recent statistics indicate that between 70-80 percent of all health related problems are either precipitated or aggravated by stress and it is estimated that 75-90% of all healthcare visits still result from stress related health problems. Conservatively stress costs the economy billions of dollars per year. Up to 75% of sick days are stress related and the American Institute of Stress report that stress was a major factor in up to 80 percent of all work related injuries and 40 percent of workplace turnovers
Other problems associated with workplace stress include sleep problems, digestive disorders, headaches, anxiety, depression, anger and hostility, alcoholism and drug abuse, heart and cardiovascular disease have reached epidemic proportions in affluent society.
In the workplace other consequences of stress include
•lost productivity
•increased absenteeism
•increased presenteeism
•decreased concentration, mental focus
•working at 50% of capacity or less
•shorter work life
•less fun and motivation
While some of the health effects of stress include
•Migraines
•Peptic ulcers
•Irritable bowel syndrome
•Hypertension
•Coronary heart disease
•Diabetes
•Asthma
One study found that those who expressed a high amount of despair had a 20% greater chance of developing atherosclerosis over a 4-year period. They suggested this was the same magnitude of increased risk as seen in a pack-a-day smoker. While another study showed that a sense of hopelessness can affect the arteries in the process of plaque build up.
As well as the effects on the immune system and an increased risk of
•Viral infections
•Allergies
•AIDS
•Cancer
•Lupus
•Arthritis
Current research reveals that psychological stress is responsible for immune suppression on a range of fronts, including T-Cell response, antibody production and breaking down the natural killer cell which fight off viruses and cancer.
Unfortunately a lot of stress goes unrecognised and we rarely take action yet a few simple strategies like the meditation I have written about above can have such a profound effect on your stress. So if you have a bit of stress in your life do the little mediation exercise I have suggested.
Other problems associated with workplace stress include sleep problems, digestive disorders, headaches, anxiety, depression, anger and hostility, alcoholism and drug abuse, heart and cardiovascular disease have reached epidemic proportions in affluent society.
In the workplace other consequences of stress include
•lost productivity
•increased absenteeism
•increased presenteeism
•decreased concentration, mental focus
•working at 50% of capacity or less
•shorter work life
•less fun and motivation
While some of the health effects of stress include
•Migraines
•Peptic ulcers
•Irritable bowel syndrome
•Hypertension
•Coronary heart disease
•Diabetes
•Asthma
One study found that those who expressed a high amount of despair had a 20% greater chance of developing atherosclerosis over a 4-year period. They suggested this was the same magnitude of increased risk as seen in a pack-a-day smoker. While another study showed that a sense of hopelessness can affect the arteries in the process of plaque build up.
As well as the effects on the immune system and an increased risk of
•Viral infections
•Allergies
•AIDS
•Cancer
•Lupus
•Arthritis
Current research reveals that psychological stress is responsible for immune suppression on a range of fronts, including T-Cell response, antibody production and breaking down the natural killer cell which fight off viruses and cancer.
Unfortunately a lot of stress goes unrecognised and we rarely take action yet a few simple strategies like the meditation I have written about above can have such a profound effect on your stress. So if you have a bit of stress in your life do the little mediation exercise I have suggested.
Stress Management – Meditation exercise
Meditation is a great and simple way to deal with life’s stresses. Meditation calms the mind and the body. It produces a state of being all of us can learn and apply our daily lives. As a part of a healthy lifestyle, meditation can add energy, focus and enjoyment to our personal experience. With as little as ten minutes a day, significant mental and physical improvements can be gained.
As we age, our bodies and minds begin to show signs of long-term stress. Meditation strengthens and promotes continued health and vigour. It is an invaluable tool that balances our minds, bodies and spirits. Regular practice creates a marvelous integration physically, emotionally and spiritually.
Meditation for beginners
The breath
This meditation is a simple introduction if you are new to the practice. It is also recommended for experienced meditators, strengthening concentration and focus.
Close your eyes, and start to focus on your breath as you inhale and exhale.
Become aware of how the breath feels as it goes in and out of your body.
Relax your body as your breath and find your natural rhythm.
Continue to focus on your breath.
To maintain your focus it helps to keep your attention on an area where you can actually feel the breath is some way as it moves in and out, like the nose or abdomen.
If you find your mind wandering, simply bring your focus and attention back.
When starting out, you may find your mind begins to wander within seconds.
It may take many minutes before you even realize. Know that this is a natural party of the process.
With practice you will be able to continuously focus on your breath for longer periods of time. You will become aware faster that the mind has wandered.
Try this exercise for 1-5 minutes, gradually increasing your time as you improve. When you feel ready, bring your awareness back to your body and open your eyes.
Inner stability
Developing an inner stability allows us to experience and maintain emotional balance, even whilst our outer world fluxes and changes around us.
Close your eyes and notice your breath as you deeply inhale (for the count of 4) and exhale (for the count of 6). With each in breath imagine a soft calming energy entering your being, filling it with a soothing sense of peace. With each exhale, relax your muscles, breathing out any tension and worries you may be holding. Try exhaling through your mouth, as this will facilitate a 'sigh' style of relaxation.
Take your attention to the very centre of your being, and see a golden ball of energy there glowing brightly. Here is the source of all that you need to know, and all that you need to feel and experience. It is made up entirely of love. If you are ever needing guidance or needing to feel loved, supported or nurtured this is where you can go. See this golden energy grow, filling your entire being with its light. See this light expand out, filling your environment, town, country, the earth and the entire universe with its glowing energy. Allow it to radiate whatever you most desire to feel in this moment; eg. love, warmth, peace, calm, vibrancy, vitality, joy. Immerse yourself in feeling. Staying with this feeling bring your focus back to your centre and open your eyes. Take this feeling with you into the day, re-connecting with it whenever you need to.
As we age, our bodies and minds begin to show signs of long-term stress. Meditation strengthens and promotes continued health and vigour. It is an invaluable tool that balances our minds, bodies and spirits. Regular practice creates a marvelous integration physically, emotionally and spiritually.
Meditation for beginners
The breath
This meditation is a simple introduction if you are new to the practice. It is also recommended for experienced meditators, strengthening concentration and focus.
Close your eyes, and start to focus on your breath as you inhale and exhale.
Become aware of how the breath feels as it goes in and out of your body.
Relax your body as your breath and find your natural rhythm.
Continue to focus on your breath.
To maintain your focus it helps to keep your attention on an area where you can actually feel the breath is some way as it moves in and out, like the nose or abdomen.
If you find your mind wandering, simply bring your focus and attention back.
When starting out, you may find your mind begins to wander within seconds.
It may take many minutes before you even realize. Know that this is a natural party of the process.
With practice you will be able to continuously focus on your breath for longer periods of time. You will become aware faster that the mind has wandered.
Try this exercise for 1-5 minutes, gradually increasing your time as you improve. When you feel ready, bring your awareness back to your body and open your eyes.
Inner stability
Developing an inner stability allows us to experience and maintain emotional balance, even whilst our outer world fluxes and changes around us.
Close your eyes and notice your breath as you deeply inhale (for the count of 4) and exhale (for the count of 6). With each in breath imagine a soft calming energy entering your being, filling it with a soothing sense of peace. With each exhale, relax your muscles, breathing out any tension and worries you may be holding. Try exhaling through your mouth, as this will facilitate a 'sigh' style of relaxation.
Take your attention to the very centre of your being, and see a golden ball of energy there glowing brightly. Here is the source of all that you need to know, and all that you need to feel and experience. It is made up entirely of love. If you are ever needing guidance or needing to feel loved, supported or nurtured this is where you can go. See this golden energy grow, filling your entire being with its light. See this light expand out, filling your environment, town, country, the earth and the entire universe with its glowing energy. Allow it to radiate whatever you most desire to feel in this moment; eg. love, warmth, peace, calm, vibrancy, vitality, joy. Immerse yourself in feeling. Staying with this feeling bring your focus back to your centre and open your eyes. Take this feeling with you into the day, re-connecting with it whenever you need to.
Meditation
As someone who practices meditation daily I can honestly say it has saved my life and is the single most important factor in overcoming major trauma in my life. Last year, despite finding no negative outcomes against me, the Western Australian media had totally destroyed my professional and personal reputation. In the coroners court the absence of rules of evidence meant that anyone can say anything even 5th person hearsay or make wild and unsubstantiated claims and it is reported as evidence and put on the front page of the paper, as it was in my case. My whole life seemed shattered at the time, what had taken me 25 years to build up was taken from me in days and I had done nothing wrong. My response, more meditation and through the mediation and my writing I got immense clarity and my new direction. It is really only when you take the time to stop and take control of your mind do you really see what is important.
Meditation is about learning to control the mind and not allowing it to control you. Meditation has been practiced by most cultures for thousands of years. However, the first Western study was not until the 1960s at Harvard Medical School. Today, many doctors advise their patients to meditate to reduce stress or blood pressure and to help manage other health problems and meditation classes are run all over the country. Research has shown the benefits of meditation in reversing the effects of cardiovascular disease and aging. From what I can glean from the scientific literature meditation adds about five years to your youth span.
In case you’re thinking “it is not for me” it will benefit everyone and so many chronic health conditions. Meditation shows benefits for many conditions including: anxiety disorders, panic attacks, headaches, back pain, arthritis, cancer pain, other chronic pain conditions, gastro-intestinal problems such as irritable bowel syndrome, hypertension, angina and heart disease, menopausal hot flashes, pre-menstrual syndrome, infertility, and nausea and vomiting associated with chemotherapy. It has also been used to stabilise blood sugar levels in diabetics and reduce their recovery time after surgery, reduce the length of labour and discomfort during childbirth, strengthen the immune system to reduce upper respiratory infections and help cancer and HIV patients. So you can see it has many benefits for everyone not just me.
Meditation has been demonstrated to dampen the busy neural activity in the frontal cortex. This probably exerts its therapeutic effects in part by quieting the emotional activity in the internal monologue of the frontal lobes. During meditation the alpha brainwave activity typically rises during the first few minutes followed by increases in theta levels. It appears that the level of brainwave change is also associated with the length of time subjects have practised meditation. Theta is the key brain wave that changes during meditation and increases with the number of weeks practised. The slower brain wave patterns such as theta waves indicate reduced arousal level of the cortex and the more you are in control.
Research shows meditation reduces the level of the stress hormones adrenaline and cortisol. Elevated cortisol is closely linked with cardio vascular disease as well as other forms of chronic illness. In a study, people who meditated had decreased cortisol (the major stress hormone) during and between meditating. These levels remained lower even after the meditation compared to people who did not meditate. Research shows that increasing meditation increases the activity of the left prefrontal cortex. Depressed, stressed or angry people tend to have greater activity on the right side, whereas the left prefrontal cortex is associated with happiness and relaxation. These studies have shown that people who meditate also produce more melatonin, the body’s main sleep chemical, than people who do not meditate. Related to this is a study of insomniacs in which 75% were able to sleep after regularly practicing meditation. Another by product of anxiety and tension is a rise in the level of lactate in the blood. Meditation decreases the level of lactate in the blood, bringing on a feeling of calm.
Other studies have shown that DHEA (Dehydroepiandrosterone, also known as the youth hormone) is much higher in people who meditate. People who meditate regularly have average DHEA levels of people ten years younger than they are! Various studies have shown that those people meditating for more than five years had an average biological age that was 12 years lower than their chronological age.
Meditation also reduces activity in the nervous system. It stimulates the parasympathetic branch of the autonomic nervous system; as a result the area of the system which is responsible for calm energy becomes dominant. When the body runs on calm energy it doesn’t tire as quickly. When the parasympathetic nervous system is stimulated, a person is able to think more clearly and perform at a comfortable level for longer periods of time. Taking deep breaths and smiling also stimulate the parasympathetic nervous system.
The major benefits of stimulating the parasympathetic nervous system include:
• Improved thinking, clarity of mind, creativity and memory;
• Reduced cardiovascular disease;
• Improved sleep;
• Increased sense of relaxation;
• Reduced pain and reduced healing time;
• Reduced stress and anxiety;
• Enhanced psychological well being;
• Enhanced self control, confidence and self esteem; and
• A longer life.
There are also many potential social benefits of meditation. In the 1990s, Professor John S. Hagelin brought 4,000 TM practitioners to Washington, D.C. He had designed an experiment to test the effects that mass meditation would have on homicide, rape and assault (HRA) crimes in the city district. The idea of the experiment was to reduce crime through reducing social stress, as it is a fact that 44 percent of Americans suffer from stress-related health problems. Meditation was conducted for fifteen to twenty minutes in the morning and again in the evening. The experiment worked on the theory of a collective consciousness in the community, so theoretically there would be a drop in communal stress also. During the course of the experiment HRA crimes dropped by up to 24.6% and overall violent crime rates dropped by 15.6%. It was estimated that if this experiment were continued for the long term, HRA crimes would be reduced by 48%.
Premeditated crime, such as robbery, was not reduced during the experiment, but unpremeditated, violent crime was reduced in proportion to the number of people meditating. This study was very thorough and built upon more than 100 previous studies. It’s amazing to think we could reduce violent crime if more people meditated. The social benefits would be enormous, not to mention huge savings of taxpayer money. On this topic there are many cases now where meditation is used in prisons and has a dramatic impact on reducing violent and aggressive behaviour of the prisoners. Maybe we should get everyone to do it so we don’t have so many prisoners.
Probably most confusing about meditation are the different styles and the claims by some schools that their meditation is the only way (which sounds a bit too much like promoting a religion). Meditation can come in many forms. For example, the connection to nature (looking out on trees) by hospital patients mentioned earlier can be considered a form of meditation. My perspective is that there are many forms of meditation and each has some benefit.
Prayer is probably the best known form of meditation. Every culture has adopted some type of meditation to suit its needs and desires. For example prayer is usually used to ask for help and guidance, whereas mindfulness meditation is used to release unwanted emotions and focus on the inner light. The common link between all forms of meditation is the purpose of quieting one’s mind. The idea is not to remove stimuli but to focus concentration upon one healing element. When the mind is at ease and filled with peace and tranquillity it cannot become stressed, worried or depressed and therefore can become refreshed and rejuvenated.
Meditation is about learning to control the mind and not allowing it to control you. Meditation has been practiced by most cultures for thousands of years. However, the first Western study was not until the 1960s at Harvard Medical School. Today, many doctors advise their patients to meditate to reduce stress or blood pressure and to help manage other health problems and meditation classes are run all over the country. Research has shown the benefits of meditation in reversing the effects of cardiovascular disease and aging. From what I can glean from the scientific literature meditation adds about five years to your youth span.
In case you’re thinking “it is not for me” it will benefit everyone and so many chronic health conditions. Meditation shows benefits for many conditions including: anxiety disorders, panic attacks, headaches, back pain, arthritis, cancer pain, other chronic pain conditions, gastro-intestinal problems such as irritable bowel syndrome, hypertension, angina and heart disease, menopausal hot flashes, pre-menstrual syndrome, infertility, and nausea and vomiting associated with chemotherapy. It has also been used to stabilise blood sugar levels in diabetics and reduce their recovery time after surgery, reduce the length of labour and discomfort during childbirth, strengthen the immune system to reduce upper respiratory infections and help cancer and HIV patients. So you can see it has many benefits for everyone not just me.
Meditation has been demonstrated to dampen the busy neural activity in the frontal cortex. This probably exerts its therapeutic effects in part by quieting the emotional activity in the internal monologue of the frontal lobes. During meditation the alpha brainwave activity typically rises during the first few minutes followed by increases in theta levels. It appears that the level of brainwave change is also associated with the length of time subjects have practised meditation. Theta is the key brain wave that changes during meditation and increases with the number of weeks practised. The slower brain wave patterns such as theta waves indicate reduced arousal level of the cortex and the more you are in control.
Research shows meditation reduces the level of the stress hormones adrenaline and cortisol. Elevated cortisol is closely linked with cardio vascular disease as well as other forms of chronic illness. In a study, people who meditated had decreased cortisol (the major stress hormone) during and between meditating. These levels remained lower even after the meditation compared to people who did not meditate. Research shows that increasing meditation increases the activity of the left prefrontal cortex. Depressed, stressed or angry people tend to have greater activity on the right side, whereas the left prefrontal cortex is associated with happiness and relaxation. These studies have shown that people who meditate also produce more melatonin, the body’s main sleep chemical, than people who do not meditate. Related to this is a study of insomniacs in which 75% were able to sleep after regularly practicing meditation. Another by product of anxiety and tension is a rise in the level of lactate in the blood. Meditation decreases the level of lactate in the blood, bringing on a feeling of calm.
Other studies have shown that DHEA (Dehydroepiandrosterone, also known as the youth hormone) is much higher in people who meditate. People who meditate regularly have average DHEA levels of people ten years younger than they are! Various studies have shown that those people meditating for more than five years had an average biological age that was 12 years lower than their chronological age.
Meditation also reduces activity in the nervous system. It stimulates the parasympathetic branch of the autonomic nervous system; as a result the area of the system which is responsible for calm energy becomes dominant. When the body runs on calm energy it doesn’t tire as quickly. When the parasympathetic nervous system is stimulated, a person is able to think more clearly and perform at a comfortable level for longer periods of time. Taking deep breaths and smiling also stimulate the parasympathetic nervous system.
The major benefits of stimulating the parasympathetic nervous system include:
• Improved thinking, clarity of mind, creativity and memory;
• Reduced cardiovascular disease;
• Improved sleep;
• Increased sense of relaxation;
• Reduced pain and reduced healing time;
• Reduced stress and anxiety;
• Enhanced psychological well being;
• Enhanced self control, confidence and self esteem; and
• A longer life.
There are also many potential social benefits of meditation. In the 1990s, Professor John S. Hagelin brought 4,000 TM practitioners to Washington, D.C. He had designed an experiment to test the effects that mass meditation would have on homicide, rape and assault (HRA) crimes in the city district. The idea of the experiment was to reduce crime through reducing social stress, as it is a fact that 44 percent of Americans suffer from stress-related health problems. Meditation was conducted for fifteen to twenty minutes in the morning and again in the evening. The experiment worked on the theory of a collective consciousness in the community, so theoretically there would be a drop in communal stress also. During the course of the experiment HRA crimes dropped by up to 24.6% and overall violent crime rates dropped by 15.6%. It was estimated that if this experiment were continued for the long term, HRA crimes would be reduced by 48%.
Premeditated crime, such as robbery, was not reduced during the experiment, but unpremeditated, violent crime was reduced in proportion to the number of people meditating. This study was very thorough and built upon more than 100 previous studies. It’s amazing to think we could reduce violent crime if more people meditated. The social benefits would be enormous, not to mention huge savings of taxpayer money. On this topic there are many cases now where meditation is used in prisons and has a dramatic impact on reducing violent and aggressive behaviour of the prisoners. Maybe we should get everyone to do it so we don’t have so many prisoners.
Probably most confusing about meditation are the different styles and the claims by some schools that their meditation is the only way (which sounds a bit too much like promoting a religion). Meditation can come in many forms. For example, the connection to nature (looking out on trees) by hospital patients mentioned earlier can be considered a form of meditation. My perspective is that there are many forms of meditation and each has some benefit.
Prayer is probably the best known form of meditation. Every culture has adopted some type of meditation to suit its needs and desires. For example prayer is usually used to ask for help and guidance, whereas mindfulness meditation is used to release unwanted emotions and focus on the inner light. The common link between all forms of meditation is the purpose of quieting one’s mind. The idea is not to remove stimuli but to focus concentration upon one healing element. When the mind is at ease and filled with peace and tranquillity it cannot become stressed, worried or depressed and therefore can become refreshed and rejuvenated.
Multiple Sclerosis (MS) a preventable disease
Just over a year ago a student of mine motivated me to look into multiple Sclerosis. Bruce put up a slide quoting the official authorities saying there was no link between MS and nutrition. He then presented a slide with more than 40 peer reviewed scientific papers on the link between MS and nutrition. Along with Bruce it continually confuses me as to why such supposed authorities continue to deny the existence of nutritional treatments and even worse the role of poor nutrition in the causes. Since inspiring me I have now seen dozens of people suffering from MS begin a new life through really simple changes in nutrition and one of the simplest changes follows on from one of my earlier articles on vitamin D. Many Australians just don’t get enough sun anymore. But more on that later. What is even more important is that this information can help prevent the development of MS in the beginning.
There is now overwhelming evidence of the risk of developing MS is linked to a number of environmental factors such as excessive dietary intake of saturated fats and deficiencies in polyunsaturated fatty acids, vitamin D and antioxidants (1,2). As a result of these findings good nutrition appears critical in limiting the development and ongoing effects of MS and enhance quality of life while limiting the risk of secondary conditions (3).
Over the past 200 years MS has significantly increased in incidence and prevalence. MS is a disease that effects an estimated 2.5 million people worldwide with over 18, 000 people in Australia with the disease, the incidence rate in Australia is increasing by 7% each year and financially costs approximately 2 billion dollars each year 4. It is twice as common in females (who have lower vitamin D than males) as in males and is the most frequent neurodegenerative disease in young adults 5,1. Geographically MS is common across northern Europe, Scandinavia and across the US and is much higher in incidence among whites then other racial groups (5).The disease is very rare in Japan, the Indian subcontinent and is unknown to black Africans however these groups are at significant risk to developing MS, when they go to other places to live, which supports the concept that an environmental factor is responsible for MS (5).
MS is a chronic, degenerative and autoimmune initiated inflammatory disease of the central nervous system, which may involve the brain, optic nerve or spinal cord and is characterized by demyelination (5,6). That is the myelin, that wraps around and insulates the nerve axons in the central nervous system, suffers self-destruction and degeneration (7). This means damaged myelin results in damaged nerve axons and causes the various disabilities of MS (7). It is worth noting here that myelin is around 80% lipids (fats) and cholesterol (which I have written on in past articles) makes up an indispensable component of myelin membranes (8). The inflammatory reactions are poorly controlled and result in substantial damage to the myelin (7). As a result of demyelination MS patients suffer functional impairments such as abnormal walking mechanics, poor balance, muscle weakness and fatigue which result in individuals reduced ability to perform activities of daily living (9).
The single most important factor linked to the development of MS is a reduced supply of vitamin D (7), which I have written on extensively in the past. Research has shown that the active hormonal form of vitamin D, 1,25-dihydroxyvitamin is a natural immune system regulator with anti-inflammatory action (10). Vitamin D is received from two sources, diet and sunshine, however it is considered diet provides insignificant amounts and therefore sensible exposure to sunlight is considered the most effective source (11). Even Scandinavian diets (rich in oily fish) scarcely exceed a few hundred IU/d of vitamin D (12). Sunshine is therefore the principal natural source of vitamin D, providing approximately 90% of requirements. Sunbathing can provide 10,000–20,000 IU in 15–30 min, but this will only last a few weeks before it needs to be replenished (13,14). It is interesting to note that women generally have lower serum levels than men (15,16) and have significantly higher levels of MS.
There is a 41% decrease in MS risk for every 50 nanomoles per liter increase in vitamin D (1,25-hydroxyvitamin) in the blood. The prevalence of MS is highest where environmental supplies of vitamin D are lowest (18). There is significant epidemiological data from Australia that shows a very strong correlation between vitamin D supply from ultraviolet (UV) radiation and MS prevalence (7). The correlation is indeed stronger than that of UV radiation exposure and melanoma development (7). Globally countries of high latitudes with insufficient UV radiation for most of the year report a higher incidence of MS 19,20. One case-control study has also shown that vitamin D status in individuals at the time of diagnosis of MS is significantly lower then healthy controls, indicating a further link (19).
It is theorized that vitamin D deficiencies may lead to an increase in T-helper cell autoimmune responses and therefore resulting in excessive damage to the myelin and MS symptoms (21).
Vitamin D supply through dietary intake also appears critical, as it has been reported that through vitamin D supplements there is an inverse relationship with MS (19). The role of vitamin D is supported by animal studies where mouse models have shown that vitamin D deficient mice succumb faster to MS but once administered with vitamin D the symptoms diminish (22).
The idea that an increase in saturated fats in modern diets may result in increased risks for MS (and diabetes type 2) has been known since the early 1950’s and reinforced on several occasions (23). Epidemiological studies in Norway have shown inland farming communities with high intake of animal products had higher MS incidence rates then coastal communities where consumption of fish is high while subsequent studies have also shown a negative correlation between MS and the consumption of fish, fruits and vegetables (23). Any wonder the rates of MS are increasing so fast in Australia knowing the poor diet most kids are having. It has been shown that MS sufferers have deficiencies in essential polyunsaturated fatty acids (PUFA), primarily the omega 3 fats which is demonstrated in that the lipid and fatty acid composition in plaque tissue from the MS brain is altered compared to the normal brain white matter (1).
It is believed that humans evolved on a diet with a ratio of omega-6 to omega-3 of approximately 1:1 where as in western diets the ratio is varied between 15:1 – 20:1 24. We just have too much vegetable oil (omega 6) in our diet. It is literally added liberally to all processed foods.
A large study conducted over a 35 year period showed MS patients on a diet with low saturated fat and supplementation with cod liver oil provided long term benefits on mortality, relapse severity and disability, particularly if initiated during the earliest stages of MS (25). The results of this have shown that MS patients can expect to survive and be ambulant and otherwise normal to an advanced age if following an extreme low fat diet and omega-3 supplementation (26). The rarity of MS in the Japanese, whose diet consist of low saturated fat and high omega-3 fatty acids is another indication of the role of omega 3 oils in MS (27). There is now significant evidence to show it is a contributing factor to the development of the disease in conjunction with other environmental factors (7).
The development of MS is also believed to be linked to oxidant stress in the body from a lack of antioxidants (28). Along with other possible environmental factors the actual role of oxidative stress in patients with MS is poorly understood (29). The brain and nervous system are particularly susceptible to oxidative damage due to the low content of antioxidants in this area of the body due to them having to be imported (30).
Studies have shown that oxidative stress causes an activation where the production of pro-inflammatory chemical messengers called cytokines occurs which then contributes to the process of demyelination (31). Having sufficient antioxidants therefore ensures neuroprotection through suppression of inflammation, this limits the effects of MS (29,31,32).
Oligodendrocytes, a particular type of brain cell, that produce the extensive myelin sheaths are known to be particularly vulnerable to oxidative stress, this helps explain the lack of remyelination during remission stages 1. Oxidation (free radicals) literally stops the repair work on any damage to the myelin sheath.
In helping to prevent and restrict the development of MS there are a number of recommendations that can be applied as determined through scientific studies:
• Regular moderate sun exposure (15-30 min/day)
• Decreased intake of saturated fat and omega-6 PUFA accompanied with an increased consumption of omega-3 PUFA through consumption of fish and supplementation
• Daily supplement of vitamin D to ensure circulating level of vitamin D remains between 100 – 150 nanomoles per liter
• Consume at least 5-7 serves of antioxidant rich fruits and vegetables each day and supplement.
Acknowledgements. Bruce Greatwitch
References:
1. Meeteren et. al. 2005
2. Liuzzi et. al. 2007
3. Timmerman, Stuifbergin 1999
4. MS research Australia 2008
5. Undurti 2003
6. Kanwar, 2005
7. Embry 2004
8. Saher et al 2005
9. White et. al. 2004
10. Van Amerongen 2004
11. Cantorna, Mahon 2004
12. Mark and Carson, 2006
13. Hollis, 2005
14. Vieth, 2007
15. Yetley, 2008
16. Zadshir et al 2005
17. Anonymous 2007
18. VanAmerongen et. al. 2004
19. Barnes et. al. 2007
20. Kampman et. al. 2007
21. Toohey 2004
22. Mandavilli 2007
23. Nordvik et. al. 2000
24. Simopoulos 2002
25. Swank cited in Weinstock-Guttman et. al. 2005
26. Swank, Goodwin 2003
27. Undurti 2003
28. Lutskii, Esaulenko 2007
29. Koch et. al. 2006
30. Syburra, Passi, 1999
31. Gonsette 2008
32. Gilgun-Sherki et. al. 2004
There is now overwhelming evidence of the risk of developing MS is linked to a number of environmental factors such as excessive dietary intake of saturated fats and deficiencies in polyunsaturated fatty acids, vitamin D and antioxidants (1,2). As a result of these findings good nutrition appears critical in limiting the development and ongoing effects of MS and enhance quality of life while limiting the risk of secondary conditions (3).
Over the past 200 years MS has significantly increased in incidence and prevalence. MS is a disease that effects an estimated 2.5 million people worldwide with over 18, 000 people in Australia with the disease, the incidence rate in Australia is increasing by 7% each year and financially costs approximately 2 billion dollars each year 4. It is twice as common in females (who have lower vitamin D than males) as in males and is the most frequent neurodegenerative disease in young adults 5,1. Geographically MS is common across northern Europe, Scandinavia and across the US and is much higher in incidence among whites then other racial groups (5).The disease is very rare in Japan, the Indian subcontinent and is unknown to black Africans however these groups are at significant risk to developing MS, when they go to other places to live, which supports the concept that an environmental factor is responsible for MS (5).
MS is a chronic, degenerative and autoimmune initiated inflammatory disease of the central nervous system, which may involve the brain, optic nerve or spinal cord and is characterized by demyelination (5,6). That is the myelin, that wraps around and insulates the nerve axons in the central nervous system, suffers self-destruction and degeneration (7). This means damaged myelin results in damaged nerve axons and causes the various disabilities of MS (7). It is worth noting here that myelin is around 80% lipids (fats) and cholesterol (which I have written on in past articles) makes up an indispensable component of myelin membranes (8). The inflammatory reactions are poorly controlled and result in substantial damage to the myelin (7). As a result of demyelination MS patients suffer functional impairments such as abnormal walking mechanics, poor balance, muscle weakness and fatigue which result in individuals reduced ability to perform activities of daily living (9).
The single most important factor linked to the development of MS is a reduced supply of vitamin D (7), which I have written on extensively in the past. Research has shown that the active hormonal form of vitamin D, 1,25-dihydroxyvitamin is a natural immune system regulator with anti-inflammatory action (10). Vitamin D is received from two sources, diet and sunshine, however it is considered diet provides insignificant amounts and therefore sensible exposure to sunlight is considered the most effective source (11). Even Scandinavian diets (rich in oily fish) scarcely exceed a few hundred IU/d of vitamin D (12). Sunshine is therefore the principal natural source of vitamin D, providing approximately 90% of requirements. Sunbathing can provide 10,000–20,000 IU in 15–30 min, but this will only last a few weeks before it needs to be replenished (13,14). It is interesting to note that women generally have lower serum levels than men (15,16) and have significantly higher levels of MS.
There is a 41% decrease in MS risk for every 50 nanomoles per liter increase in vitamin D (1,25-hydroxyvitamin) in the blood. The prevalence of MS is highest where environmental supplies of vitamin D are lowest (18). There is significant epidemiological data from Australia that shows a very strong correlation between vitamin D supply from ultraviolet (UV) radiation and MS prevalence (7). The correlation is indeed stronger than that of UV radiation exposure and melanoma development (7). Globally countries of high latitudes with insufficient UV radiation for most of the year report a higher incidence of MS 19,20. One case-control study has also shown that vitamin D status in individuals at the time of diagnosis of MS is significantly lower then healthy controls, indicating a further link (19).
It is theorized that vitamin D deficiencies may lead to an increase in T-helper cell autoimmune responses and therefore resulting in excessive damage to the myelin and MS symptoms (21).
Vitamin D supply through dietary intake also appears critical, as it has been reported that through vitamin D supplements there is an inverse relationship with MS (19). The role of vitamin D is supported by animal studies where mouse models have shown that vitamin D deficient mice succumb faster to MS but once administered with vitamin D the symptoms diminish (22).
The idea that an increase in saturated fats in modern diets may result in increased risks for MS (and diabetes type 2) has been known since the early 1950’s and reinforced on several occasions (23). Epidemiological studies in Norway have shown inland farming communities with high intake of animal products had higher MS incidence rates then coastal communities where consumption of fish is high while subsequent studies have also shown a negative correlation between MS and the consumption of fish, fruits and vegetables (23). Any wonder the rates of MS are increasing so fast in Australia knowing the poor diet most kids are having. It has been shown that MS sufferers have deficiencies in essential polyunsaturated fatty acids (PUFA), primarily the omega 3 fats which is demonstrated in that the lipid and fatty acid composition in plaque tissue from the MS brain is altered compared to the normal brain white matter (1).
It is believed that humans evolved on a diet with a ratio of omega-6 to omega-3 of approximately 1:1 where as in western diets the ratio is varied between 15:1 – 20:1 24. We just have too much vegetable oil (omega 6) in our diet. It is literally added liberally to all processed foods.
A large study conducted over a 35 year period showed MS patients on a diet with low saturated fat and supplementation with cod liver oil provided long term benefits on mortality, relapse severity and disability, particularly if initiated during the earliest stages of MS (25). The results of this have shown that MS patients can expect to survive and be ambulant and otherwise normal to an advanced age if following an extreme low fat diet and omega-3 supplementation (26). The rarity of MS in the Japanese, whose diet consist of low saturated fat and high omega-3 fatty acids is another indication of the role of omega 3 oils in MS (27). There is now significant evidence to show it is a contributing factor to the development of the disease in conjunction with other environmental factors (7).
The development of MS is also believed to be linked to oxidant stress in the body from a lack of antioxidants (28). Along with other possible environmental factors the actual role of oxidative stress in patients with MS is poorly understood (29). The brain and nervous system are particularly susceptible to oxidative damage due to the low content of antioxidants in this area of the body due to them having to be imported (30).
Studies have shown that oxidative stress causes an activation where the production of pro-inflammatory chemical messengers called cytokines occurs which then contributes to the process of demyelination (31). Having sufficient antioxidants therefore ensures neuroprotection through suppression of inflammation, this limits the effects of MS (29,31,32).
Oligodendrocytes, a particular type of brain cell, that produce the extensive myelin sheaths are known to be particularly vulnerable to oxidative stress, this helps explain the lack of remyelination during remission stages 1. Oxidation (free radicals) literally stops the repair work on any damage to the myelin sheath.
In helping to prevent and restrict the development of MS there are a number of recommendations that can be applied as determined through scientific studies:
• Regular moderate sun exposure (15-30 min/day)
• Decreased intake of saturated fat and omega-6 PUFA accompanied with an increased consumption of omega-3 PUFA through consumption of fish and supplementation
• Daily supplement of vitamin D to ensure circulating level of vitamin D remains between 100 – 150 nanomoles per liter
• Consume at least 5-7 serves of antioxidant rich fruits and vegetables each day and supplement.
Acknowledgements. Bruce Greatwitch
References:
1. Meeteren et. al. 2005
2. Liuzzi et. al. 2007
3. Timmerman, Stuifbergin 1999
4. MS research Australia 2008
5. Undurti 2003
6. Kanwar, 2005
7. Embry 2004
8. Saher et al 2005
9. White et. al. 2004
10. Van Amerongen 2004
11. Cantorna, Mahon 2004
12. Mark and Carson, 2006
13. Hollis, 2005
14. Vieth, 2007
15. Yetley, 2008
16. Zadshir et al 2005
17. Anonymous 2007
18. VanAmerongen et. al. 2004
19. Barnes et. al. 2007
20. Kampman et. al. 2007
21. Toohey 2004
22. Mandavilli 2007
23. Nordvik et. al. 2000
24. Simopoulos 2002
25. Swank cited in Weinstock-Guttman et. al. 2005
26. Swank, Goodwin 2003
27. Undurti 2003
28. Lutskii, Esaulenko 2007
29. Koch et. al. 2006
30. Syburra, Passi, 1999
31. Gonsette 2008
32. Gilgun-Sherki et. al. 2004
Salt
Is salt the real problem that it is made out to be? It seems that by oversimplifying the information on salt and its relationship to health we complicate what is a really simple and important issue. After reviewing more than 100 scientific papers it became clear that salt is not the public enemy that it is made out to be, rather it appears to be an imbalance of minerals as a result of eating processed foods. And some very simple changes can make a lot of difference. This does not mean you go out and lather salt on all your food and justify it from my article, instead it means back to some common sense dietary changes.
Salt, in the form of sodium chloride, has been consumed by humans since the late Palaeolithic period, when it was used to preserve and flavour food. In modern times, however, some very limited studies and an incomplete understanding of nutrition have led to salt being labelled “public enemy number one” when it comes to blood pressure and cardiovascular disease. But is salt really so bad?
Salt in the human diet has been the subject of a great deal of research. Health professionals have, for many years, recommended reduction or even elimination of salt intake. This is mainly due to findings that link the excessive salt in the modern human diet to health problems such as high blood pressure. Yet it would be shortsighted to simply accept or reject such recommendations, as there are other factors involved requiring further investigation.
Salt intake is widely recognised by public health and medical organisations as the leading cause of blood pressure disparities (1). However, it is simply not valid to state that reducing salt intake will lower our prevalence of hypertension; the truth is that a number of factors, including lifestyle and nutrition, play an important role.
Sodium
Sodium is essential for many functions in the human body. The average human body contains around 90 grams of sodium, most of which is in the fluids that surround cells, some in bones and the rest retained in the cells (2). Sodium is passively absorbed and hence excess intakes are easily achieved. Sodium is excreted mainly by the kidneys; therefore a high sodium intake must be balanced with a large intake of water and other fluids. Sodium is the main component of the body’s extracellular fluids; it helps carry nutrients into and waste products out of the cells, regulates body functions such as blood pressure and fluid volume and works on the lining of blood vessels to keep the pressure balance normal (3). So you can see it is pretty important.
Chloride (Cl), the other half of the salt molecule (NaCl), is just as important as sodium yet often ignored. Chloride is essential for the production of hydrochloric acid, which is necessary to digest proteins in the gut and is essential for destroying bacteria and other potentially toxic microbes.
How much salt?
In terms of the adequate amount of daily intake of salt, various organizations, including the National Academy of Sciences’ Institute of Medicine, have published recommendations for daily sodium intake between 1,500 milligrams (mg) and 2,400mg per day for healthy adults (4)
The main regulators of sodium levels in the body are the kidneys. If sodium levels drop too low, the hormone aldosterone is released and this increases the amount of sodium held in the body by reducing the amount lost in urine. Excessive sodium loss is very rare, but low sodium levels in the body can be dangerous if not treated. Some people do not get rid of enough sodium through their urine; this causes the body to retain water, resulting in swelling of the body and, with the increased blood and fluid volume, in turn causes high blood pressure (5). The high blood pressure puts a strain on the heart, which must work harder to pump the increased volume of blood (Fox 2007). This is one reason that many health professionals recommend a reduction of salt intake—to reduce the risk of excess sodium in the blood; they believe that lower sodium intake has a beneficial effect on blood pressure. Thus people with existing hypertension and kidney disease may benefit from a reduction in salt intake.
Health problems
While there is evidence to suggest that salt plays a role in hypertension, it is a bit simplistic to target salt and ignore information that contradicts this. It is critical that we assess all the information available. It is important to take a multidimensional approach and look at the whole body. The increase in blood pressure as a result of increased salt intake may be due to the human kidney’s inability to excrete large amounts of (6,7,8). Results from various studies—including epidemiological, animal and migration studies as well as randomised trials—support the claim that as dietary salt increases, blood pressure increases (6). However, in humans at least, individuals seem to vary significantly in how they tolerate salt. Some people appear to be salt sensitive or have certain conditions that predispose them to hypertension.
High dietary salt intake in some individuals has been shown to contribute to cardio vascular conditions including the incidence of stroke (9). Research has found that individuals with a high salt sensitivity (in particular those with hypertension) have an increased risk of cardiovascular disease and death (10). High dietary salt intake can increase the risk of osteoporosis because of high urinary calcium excretion. In particular, it has been found that individuals with hypertension excrete high levels of calcium in their urine (11,12). However, provided that intake of calcium and potassium are at recommended levels, the risk of osteoporosis is low (13).
Salt is not the problem
So what is the problem? Research dating back to 1964 contradicts the simplicity of the link between salt and hypertension (14). In one study, a significant blood pressure decline was observed as a result of acute dietary salt increase (14). While limited studies of salt levels and blood pressure support the salt-hypertension link, the data are somewhat contradictory (14-23). It appears that this link affects only those with existing health conditions, not healthy persons. The question that remains is whether beneficial hypertensive effects of sodium restriction will outweigh its hazards.
Inadequate salt intake has also been associated with undesirable metabolic situations such as alteration in plasma lipoproteins and inflammation (24), a potential increase in cardiovascular stress, and increased serum cholesterol, triglycerides and insulin resistance (25). Contrary to common belief, the effects of low-salt diets—the unfavourable effects on blood coagulation, inflammatory and metabolic disturbances—outweigh the benefits of lowered blood pressure (Nakandakare et al. 2008). One study found that low-salt diets can actually cause harm to people with high blood pressure (26,27). So too little salt has greater adverse effect on health than too much salt. Epidemiological evidence suggests that a reduction in salt can decrease the risk of coronary disease significantly for overweight patients (28); however, low-salt diets are not warranted in patients with normal blood pressure (24).
Many studies show that hypertension is not related solely to dietary salt intake but to other factors such as a sedentary lifestyle, alcohol consumption, protein intake and lack of potassium, calcium and magnesium (29,30,31). The most realistic strategy for preventing and treating hypertension is not focusing on one risk factor but instead on a combination of interventions to reduce a number of risk factors (30). A proven effective intervention is Dietary Approaches to Stop Hypertension (DASH), which is a diet rich in fruit and vegetables, therefore rich in potassium, magnesium and other minerals (30,32). Not only has the DASH diet shown a beneficial effect on lowering blood pressure but also it is accompanied by the benefits of cholesterol-lowering and high antioxidant content, which could improve overall health and lower the risk of other diseases (32).
Studies indicate that only about 12% of subjects in a society with a high salt intake (eight grams to 12 grams of salt per day) will become hypertensive (33). According to a Tufts University research group (1997), only people with high blood pressure should be advised to limit sodium. Data from several large studies show that when adults meet or exceed the recommended dietary allowance of calcium, potassium and magnesium, the simultaneous ingestion of a diet high in sodium chloride is not associated with high blood pressure (34).
Overall there is only a weak relationship between dietary salt intake and high blood pressure in the general population (10). The effects of dietary salt on blood pressure are governed by “salt sensitivity” of individuals where large blood pressure changes can occur due to varying levels of salt intake (Franco and Oparil 2006). To compound the issue, research shows that sodium reduction in younger people frequently results in increased blood pressure, whereas those over 45 generally experience decreased blood pressure when sodium intake is restricted (34,35). Diet can also affect the response of dietary salt intake on blood pressure. An appropriate diet and a high potassium intake can curb the rise in blood pressure associated with an increase in dietary salt intake (10,37). More than 25 separate studies show that increasing potassium intake (without decreasing sodium) is an effective way to lower blood pressure. One of those studies demonstrated that with just one daily serving of a potassium-rich food the risk of death by stroke may be cut by as much as half (21). So why don’t we take this approach?
An eight-year study found those on low-salt diets had more than four times as many heart attacks as those on normal-sodium diets—the exact opposite of what the “salt hypothesis” would have predicted 38. Scientists at the University of Toronto concluded that limiting salt in the diet has no effect on people with normal blood pressure. In another study, 269 medical students were tracked; about 50% had no change in blood pressure when salt intake was increased by 12 times 39. Half of the remainder had a rise in blood pressure and the other half experienced a drop in blood pressure.
Data from the National Health and Nutrition Examination Survey found that individuals with the lowest sodium intake had a 20% higher chance of dying from a cardiovascular cause than individuals with the highest sodium intake (40). An earlier study also found an independent relationship between levels of sodium measured in urine and subsequent heart attacks and strokes: the lower the levels, the higher the rate of heart attacks and strokes (41). So not enough salt may kill you.
In support of this most of the big observational studies indicate an inverse relationship between salt intake and health outcomes (21). That is more salt less overall poor health. While a low salt diet may reduce blood pressure, it isn’t necessarily good for one’s overall health. It may make things worse (21) and could be outweighed by its negative effects on other health outcomes (21). In one of the big studies on hypertensive patients those who took in the least amount of salt were most likely to have heart attacks (21). A low-sodium diet also increases your resistance to insulin (21).
When salt is not salt
Some types of salts are: mine salts, sea salt and refined salt. The difference between sea salt and salt from saltshakers is that sea salt is richer in minerals such as magnesium, although it does not have iodine (42). Sea salt contains 84 different mineral elements but, during the process of refining sea salt to make “table salt,” 82 of the 84 mineral elements are extracted (43). Thus refined salt or table salt is not a healthy choice as it contains mainly sodium chloride.
The solution
Rather than viewing sodium as the direct culprit leading to various diseases, it may be more useful to look at sodium as an indicator of diets that are low in calcium, potassium and magnesium (44) while containing too many overly processed foods and soft drinks.
No single universal prescription for sodium intake can be scientifically justified (40). A healthy person can regulate a reasonable excess of salt especially if the diet contains a balance of other essential minerals. People with existing health problems may require a reduction in salt from their diet based on their individual needs and advice by health professionals but it is probably more important to increase their other mineral levels.
Rather than eradicate salt from the diet altogether, it makes more sense to restrict the ingestion of salt to a feasible level while encouraging consumption of organic sodium salts in conjunction with good nutrition to control blood pressure, promoting vascular health and preserving bone density (45). It is easy to increase the potassium in your diet. High potassium fruits include apricots, bananas, melons and citrus fruits. Vegetables with good amounts of potassium are mushrooms, spinach, asparagus, potatoes, green beans, avocados, lima beans, winter squash and cauliflower. Other foods high in potassium include whole grain products, seafood and dry beans such as peas and lentils. All these foods contain significant amounts of magnesium and calcium, which will also contribute to the lowering of blood pressure.
It is too simplistic to target salt as the enemy. Rarely is anything simple when we are dealing with the human body. If we adopt a healthy diet with the nutrients we need and reduce our intake of processed foods and soft drinks, we reduce not only blood pressure but also many other forms of chronic illness including all forms of cardiovascular disease. What I don’t understand is why we don’t target the real culprits? We need to adopt a multidimensional view of health and illness rather than looking at just one aspect. For the sake of our health, we must look at the entire picture.
References
1. Antonios and MacGregor 1996
2. Reavley 1998
3. Greeley 1997
4. Mayo Clinic 2007
5. Fox 2007
6. Appel 2008
7. Menton et al. 2005
8. Havas et al. 2008
9. Sergei and Mongin 2007
10. Franco and Oparl 2006
11. Gilbert and Heiser 2005
12. Navidi et al. 1995
13. Heaney 2006.
14. Brown et al. 1964
15. Freedman et al. 2001
16. Alderman 2000
17. Cassels 2008
18. McCarron et al. 1997 and 1998
19. Freeman and Petitti 2002
20. Graudal et al. 1998
21. Cohen et al. 2006
22. Meneton et al. 2005
23. Taubes 1998
24. Nakandakare et al. 2008
25. Ivanovski et al. 2005
26. Rivera 1999;
27. Grassi et al. 2002
28. McCarty 2003
29. Boyles 2003
30. Suter et al. 2002
31. Cann 2005
32. Beilin et al. 2001
33. Finn 1999
34. McCarron et al. 1997
35. Ian and Robertson 2003
36. Overlack et al. 1993
37. Appel 2008
38. Young 2008
39. Freeman and Petitti 2002
40. Alderman 2000
41. Alderman 1995
42. Largeman 2006
43. Dearing 2008
44. Boyles 2003
45. McCarty 2003
Salt, in the form of sodium chloride, has been consumed by humans since the late Palaeolithic period, when it was used to preserve and flavour food. In modern times, however, some very limited studies and an incomplete understanding of nutrition have led to salt being labelled “public enemy number one” when it comes to blood pressure and cardiovascular disease. But is salt really so bad?
Salt in the human diet has been the subject of a great deal of research. Health professionals have, for many years, recommended reduction or even elimination of salt intake. This is mainly due to findings that link the excessive salt in the modern human diet to health problems such as high blood pressure. Yet it would be shortsighted to simply accept or reject such recommendations, as there are other factors involved requiring further investigation.
Salt intake is widely recognised by public health and medical organisations as the leading cause of blood pressure disparities (1). However, it is simply not valid to state that reducing salt intake will lower our prevalence of hypertension; the truth is that a number of factors, including lifestyle and nutrition, play an important role.
Sodium
Sodium is essential for many functions in the human body. The average human body contains around 90 grams of sodium, most of which is in the fluids that surround cells, some in bones and the rest retained in the cells (2). Sodium is passively absorbed and hence excess intakes are easily achieved. Sodium is excreted mainly by the kidneys; therefore a high sodium intake must be balanced with a large intake of water and other fluids. Sodium is the main component of the body’s extracellular fluids; it helps carry nutrients into and waste products out of the cells, regulates body functions such as blood pressure and fluid volume and works on the lining of blood vessels to keep the pressure balance normal (3). So you can see it is pretty important.
Chloride (Cl), the other half of the salt molecule (NaCl), is just as important as sodium yet often ignored. Chloride is essential for the production of hydrochloric acid, which is necessary to digest proteins in the gut and is essential for destroying bacteria and other potentially toxic microbes.
How much salt?
In terms of the adequate amount of daily intake of salt, various organizations, including the National Academy of Sciences’ Institute of Medicine, have published recommendations for daily sodium intake between 1,500 milligrams (mg) and 2,400mg per day for healthy adults (4)
The main regulators of sodium levels in the body are the kidneys. If sodium levels drop too low, the hormone aldosterone is released and this increases the amount of sodium held in the body by reducing the amount lost in urine. Excessive sodium loss is very rare, but low sodium levels in the body can be dangerous if not treated. Some people do not get rid of enough sodium through their urine; this causes the body to retain water, resulting in swelling of the body and, with the increased blood and fluid volume, in turn causes high blood pressure (5). The high blood pressure puts a strain on the heart, which must work harder to pump the increased volume of blood (Fox 2007). This is one reason that many health professionals recommend a reduction of salt intake—to reduce the risk of excess sodium in the blood; they believe that lower sodium intake has a beneficial effect on blood pressure. Thus people with existing hypertension and kidney disease may benefit from a reduction in salt intake.
Health problems
While there is evidence to suggest that salt plays a role in hypertension, it is a bit simplistic to target salt and ignore information that contradicts this. It is critical that we assess all the information available. It is important to take a multidimensional approach and look at the whole body. The increase in blood pressure as a result of increased salt intake may be due to the human kidney’s inability to excrete large amounts of (6,7,8). Results from various studies—including epidemiological, animal and migration studies as well as randomised trials—support the claim that as dietary salt increases, blood pressure increases (6). However, in humans at least, individuals seem to vary significantly in how they tolerate salt. Some people appear to be salt sensitive or have certain conditions that predispose them to hypertension.
High dietary salt intake in some individuals has been shown to contribute to cardio vascular conditions including the incidence of stroke (9). Research has found that individuals with a high salt sensitivity (in particular those with hypertension) have an increased risk of cardiovascular disease and death (10). High dietary salt intake can increase the risk of osteoporosis because of high urinary calcium excretion. In particular, it has been found that individuals with hypertension excrete high levels of calcium in their urine (11,12). However, provided that intake of calcium and potassium are at recommended levels, the risk of osteoporosis is low (13).
Salt is not the problem
So what is the problem? Research dating back to 1964 contradicts the simplicity of the link between salt and hypertension (14). In one study, a significant blood pressure decline was observed as a result of acute dietary salt increase (14). While limited studies of salt levels and blood pressure support the salt-hypertension link, the data are somewhat contradictory (14-23). It appears that this link affects only those with existing health conditions, not healthy persons. The question that remains is whether beneficial hypertensive effects of sodium restriction will outweigh its hazards.
Inadequate salt intake has also been associated with undesirable metabolic situations such as alteration in plasma lipoproteins and inflammation (24), a potential increase in cardiovascular stress, and increased serum cholesterol, triglycerides and insulin resistance (25). Contrary to common belief, the effects of low-salt diets—the unfavourable effects on blood coagulation, inflammatory and metabolic disturbances—outweigh the benefits of lowered blood pressure (Nakandakare et al. 2008). One study found that low-salt diets can actually cause harm to people with high blood pressure (26,27). So too little salt has greater adverse effect on health than too much salt. Epidemiological evidence suggests that a reduction in salt can decrease the risk of coronary disease significantly for overweight patients (28); however, low-salt diets are not warranted in patients with normal blood pressure (24).
Many studies show that hypertension is not related solely to dietary salt intake but to other factors such as a sedentary lifestyle, alcohol consumption, protein intake and lack of potassium, calcium and magnesium (29,30,31). The most realistic strategy for preventing and treating hypertension is not focusing on one risk factor but instead on a combination of interventions to reduce a number of risk factors (30). A proven effective intervention is Dietary Approaches to Stop Hypertension (DASH), which is a diet rich in fruit and vegetables, therefore rich in potassium, magnesium and other minerals (30,32). Not only has the DASH diet shown a beneficial effect on lowering blood pressure but also it is accompanied by the benefits of cholesterol-lowering and high antioxidant content, which could improve overall health and lower the risk of other diseases (32).
Studies indicate that only about 12% of subjects in a society with a high salt intake (eight grams to 12 grams of salt per day) will become hypertensive (33). According to a Tufts University research group (1997), only people with high blood pressure should be advised to limit sodium. Data from several large studies show that when adults meet or exceed the recommended dietary allowance of calcium, potassium and magnesium, the simultaneous ingestion of a diet high in sodium chloride is not associated with high blood pressure (34).
Overall there is only a weak relationship between dietary salt intake and high blood pressure in the general population (10). The effects of dietary salt on blood pressure are governed by “salt sensitivity” of individuals where large blood pressure changes can occur due to varying levels of salt intake (Franco and Oparil 2006). To compound the issue, research shows that sodium reduction in younger people frequently results in increased blood pressure, whereas those over 45 generally experience decreased blood pressure when sodium intake is restricted (34,35). Diet can also affect the response of dietary salt intake on blood pressure. An appropriate diet and a high potassium intake can curb the rise in blood pressure associated with an increase in dietary salt intake (10,37). More than 25 separate studies show that increasing potassium intake (without decreasing sodium) is an effective way to lower blood pressure. One of those studies demonstrated that with just one daily serving of a potassium-rich food the risk of death by stroke may be cut by as much as half (21). So why don’t we take this approach?
An eight-year study found those on low-salt diets had more than four times as many heart attacks as those on normal-sodium diets—the exact opposite of what the “salt hypothesis” would have predicted 38. Scientists at the University of Toronto concluded that limiting salt in the diet has no effect on people with normal blood pressure. In another study, 269 medical students were tracked; about 50% had no change in blood pressure when salt intake was increased by 12 times 39. Half of the remainder had a rise in blood pressure and the other half experienced a drop in blood pressure.
Data from the National Health and Nutrition Examination Survey found that individuals with the lowest sodium intake had a 20% higher chance of dying from a cardiovascular cause than individuals with the highest sodium intake (40). An earlier study also found an independent relationship between levels of sodium measured in urine and subsequent heart attacks and strokes: the lower the levels, the higher the rate of heart attacks and strokes (41). So not enough salt may kill you.
In support of this most of the big observational studies indicate an inverse relationship between salt intake and health outcomes (21). That is more salt less overall poor health. While a low salt diet may reduce blood pressure, it isn’t necessarily good for one’s overall health. It may make things worse (21) and could be outweighed by its negative effects on other health outcomes (21). In one of the big studies on hypertensive patients those who took in the least amount of salt were most likely to have heart attacks (21). A low-sodium diet also increases your resistance to insulin (21).
When salt is not salt
Some types of salts are: mine salts, sea salt and refined salt. The difference between sea salt and salt from saltshakers is that sea salt is richer in minerals such as magnesium, although it does not have iodine (42). Sea salt contains 84 different mineral elements but, during the process of refining sea salt to make “table salt,” 82 of the 84 mineral elements are extracted (43). Thus refined salt or table salt is not a healthy choice as it contains mainly sodium chloride.
The solution
Rather than viewing sodium as the direct culprit leading to various diseases, it may be more useful to look at sodium as an indicator of diets that are low in calcium, potassium and magnesium (44) while containing too many overly processed foods and soft drinks.
No single universal prescription for sodium intake can be scientifically justified (40). A healthy person can regulate a reasonable excess of salt especially if the diet contains a balance of other essential minerals. People with existing health problems may require a reduction in salt from their diet based on their individual needs and advice by health professionals but it is probably more important to increase their other mineral levels.
Rather than eradicate salt from the diet altogether, it makes more sense to restrict the ingestion of salt to a feasible level while encouraging consumption of organic sodium salts in conjunction with good nutrition to control blood pressure, promoting vascular health and preserving bone density (45). It is easy to increase the potassium in your diet. High potassium fruits include apricots, bananas, melons and citrus fruits. Vegetables with good amounts of potassium are mushrooms, spinach, asparagus, potatoes, green beans, avocados, lima beans, winter squash and cauliflower. Other foods high in potassium include whole grain products, seafood and dry beans such as peas and lentils. All these foods contain significant amounts of magnesium and calcium, which will also contribute to the lowering of blood pressure.
It is too simplistic to target salt as the enemy. Rarely is anything simple when we are dealing with the human body. If we adopt a healthy diet with the nutrients we need and reduce our intake of processed foods and soft drinks, we reduce not only blood pressure but also many other forms of chronic illness including all forms of cardiovascular disease. What I don’t understand is why we don’t target the real culprits? We need to adopt a multidimensional view of health and illness rather than looking at just one aspect. For the sake of our health, we must look at the entire picture.
References
1. Antonios and MacGregor 1996
2. Reavley 1998
3. Greeley 1997
4. Mayo Clinic 2007
5. Fox 2007
6. Appel 2008
7. Menton et al. 2005
8. Havas et al. 2008
9. Sergei and Mongin 2007
10. Franco and Oparl 2006
11. Gilbert and Heiser 2005
12. Navidi et al. 1995
13. Heaney 2006.
14. Brown et al. 1964
15. Freedman et al. 2001
16. Alderman 2000
17. Cassels 2008
18. McCarron et al. 1997 and 1998
19. Freeman and Petitti 2002
20. Graudal et al. 1998
21. Cohen et al. 2006
22. Meneton et al. 2005
23. Taubes 1998
24. Nakandakare et al. 2008
25. Ivanovski et al. 2005
26. Rivera 1999;
27. Grassi et al. 2002
28. McCarty 2003
29. Boyles 2003
30. Suter et al. 2002
31. Cann 2005
32. Beilin et al. 2001
33. Finn 1999
34. McCarron et al. 1997
35. Ian and Robertson 2003
36. Overlack et al. 1993
37. Appel 2008
38. Young 2008
39. Freeman and Petitti 2002
40. Alderman 2000
41. Alderman 1995
42. Largeman 2006
43. Dearing 2008
44. Boyles 2003
45. McCarty 2003
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