Instead, modern medicine maintains that the average, healthy person can get all the nutrients he or she needs by eating a balanced diet.
It's a view taught to doctors at medical schools-which often devote just a day out of a five-year training programme to nutrition-and one supported by drugs regulators such as America's Food and Drug Administration (FDA). As the UK's National Health Service (NHS) states categorically on its website: "Most people can get all the vitamins and minerals they need by eating a balanced, varied diet."
Vitamin and mineral supplements are, according to this view, a waste of money. Worse, they can kill you, as headline-grabbing studies occasionally tell us. The latest-the Iowa Women's Health Study-con-cludes that older women who supplement their diet increase their risk of dying at a younger age than those who don't take supplements. Iron supplements appear to pose the greatest risk (Arch Intern Med, 2011; 171: 1625-33).
In 2008, the influential Cochrane Collaboration came to a similar conclusion that also dominated the news agenda for days afterwards. The Cochrane researchers discovered, in a meta-analysis of 67 medical trials, that people who took a high-dose antioxidant, such as vitamin A, beta-carotene (converted by the body into vitamin A) or E, were more likely to die than those who didn't take a supplement (Cochrane Database Syst Rev, 2008, 2: CD007176).
With these studies as a backdrop, the European Union is currently deliberating on the potency of vitamin and mineral supplements that can be sold in stores throughout Europe. The Alliance for Natural Health (ANH), a lobby group, fears the 'maximum permitted levels' (MPLs) of supplements will be set very low, and will have no therapeutic value.
The FDA is putting forward proposals to restrict the sale of nutritional products available in stores in the US, and even blocking those that have been introduced within the past 20 years until they pass prohibitively expensive trials.
So, can we stay healthy only by eating a balanced diet or do we need to supplement? And if we do take vitamin and mineral supplements, are we raising our chances of dying prematurely?
The average person
The baseline for adequate levels of nutrition needed to maintain a healthy body is the 'Reference Daily Intake' (RDI), which replaced the 'Recom-mended Daily Allowance' (RDA). These levels (see Factfile B) are considered to be sufficient to meet the needs of up to 98 per cent of healthy individuals, and can be obtained by eating a healthy diet, say health officials. Exceptions include pregnant and breast-feeding women, children aged from six months to five years, the over-65s and people with darker skin, all of whom should supplement with vitamin D tablets. Children should also supplement with vitamins A and C until the age of five years, according to the NHS.
However, the first problem with the one-size-fits-all approach is that few of us are either average or healthy, or both. Each of us is biochemically unique. According to nutritionist Dr Damien Downing, a research study of guinea pigs discovered that individual requirements for vitamin C differed 20-fold among the animals, and "the range of human individual requirements can be assumed to be at least as great", he said.
Our nutritional needs also vary according to our age and gender, our stress levels and our genetic profile. Some of us have an inherently higher requirement for folic acid, and vitamins B6, B12 and B2, for example, and low levels in women with this predisposition increase their risk of breast cancer (Carcinogenesis, 2001; 22: 1661-5), while those with a particular enzyme variant need far more B6 than the standard RDI suggests.
RDI levels are designed to maintain health, but are inadequate when we are ill or suffering from a chronic problem. Autistic children, for example, need far higher levels of B6 than the standard recommendation; an autistic child weighing 135 lb (60 kg) needs 1000 mg/day, one study has discovered (Autism Res Rev Intl, 1997; 11: 3)-whereas the RDI suggests just 2 mg/day for the average, healthy person.
The balanced diet
A balanced diet consists of eating sensible, and varied, amounts from the following five food groups:
- fruits and vegetables: the recommendation is to eat five portions a day;
- starchy foods, such as bread, cereals, potatoes and pasta: these should make up a third of everything we eat every day;
- meat, fish, eggs and beans: these are all sources of protein and "good sources of a range of vitamins and minerals", says the NHS; eat two portions of fish each week;
- milk and dairy foods, including cheese and yog-hurt: these are another source of protein and calcium; and
- fats and sugar: these are sources of energy, and the basis of the calorie theory of weight gain; most of us eat far too much fat and sugar, resulting in obesity, type 2 diabetes, certain cancers, heart disease and stroke, says the NHS.
But the balanced-diet approach is overly simplistic. It does not differentiate between processed and unprocessed foods, organic and mass-produced foods, individual health profiles, our age and gender, and whether we have a chronic illness. Overall, it over-looks a range of problems about the food we eat that throws into question the whole theory of a balanced diet.
The unspoken assumption of the balanced diet is that the food we eat is nutritious-it must be providing us with the vitamins and minerals our body needs to function. All food starts to lose its nutritional value from the moment it is slaughtered, picked, baked or produced, and so the fresher the food, the greater its goodness.
However, a survey of a typical supermarket, reported by Alex Renton on MailOnline (26 March 2011), revealed that:
- 'fresh' New Zealand lamb can be up to two months old when it reaches the shelves, and it even takes a month before British lamb is sold;
- bread can be 10 days old before it is sold, and can be used in our homes for days afterwards because of its preservatives and mould inhibitors, such as calcium propionate and ascorbic acid;
- eggs are sold up to 10 days after they were laid;
- fish can lay on ice for up to 12 days before it is available at the supermarket, and may stay in the shop for four further days before you buy it;
- fruit juice can be up to a year old by the time you take it home, and this is certainly the case with those cartons containing juice made from concentrates;
- 'fresh' vegetables can be up to 10 days old before they are on sale, especially if they are sourced from overseas, and baking potatoes are often six months old;
- three-quarters of the apples we eat are sourced from foreign orchards, and it can take six months before they reach our shelves. In the meantime, they are waxed to give them a shiny, 'healthy' look, and are kept in refriger-ated containers along with special gases to stop them from decaying. Bananas are around 10 days old before they are on the shelves, and those wrapped in plastic can be 25 days old;
- milk is usually three days old before we buy it, and can stay drinkable for a week or so afterwards in our refrigera-tor, thanks to pasteurization, a heating process that also removes vitamin C and other nutrients.
Intensive farming and pesticides have stripped the soil of its minerals, and this has affected the goodness of the food we eat. In 1900, wheat was 90-per-cent protein, but today, it is closer to 9 per cent; in 1948, 100 g of spinach contained around 158 mg of iron, but today, that has plummeted to just 1 mg (Gemmer E. Who Stole America's Health? Lecture, 1995).
As a result, we are lacking in essential minerals, such as magnesium, chromium and vanadium, and many people are deficient in one or all three. Indeed, such deficiencies may lie behind the growing diabetes 'epidemic', as suggested by a number of studies (Am J Clin Nutr, 1992; 55: 1161-7; Diabetes, 1980; 29: 919-25).
One study of 1995 adults found that more than 90 per cent were consuming inadequate amounts of folate, while vitamin C and magnesium intakes were low in more than 50 per cent of the group, and iron and calcium consumption was inadequate across all groups (Can J Diet Pract Res, 2007; 68: 23-9).
In a study of 433 men and 876 women in low-income groups in the UK, 25 per cent of men and 16 per cent of women were deficient in vitamin C, and were at high risk of developing scurvy (J Public Health [Oxf], 2008; 30: 456-60).
A study of vegans discovered that the food they ate contained just 46 per cent of the RDI requirement for selenium (www.rawfoodlife.com/Articles ___Research/Perfect_Food/perfect
_food.html). In fact, most of us are deficient in selenium, and this lack can trigger a range of age-related diseases such as cancer, heart disease and loss of brain function, say researchers from the Children's Hospital Oakland Research Institute in California (FASEB J, 2011; 25: 1793-814).
In an accompanying editorial, the editor of The FASEB Journal, Dr Gerald Weissman, commented: "This paper should settle any debate about the importance of taking a good, complete multivitamin every day. As this report shows, taking a multivitamin that contains selenium is a good way to prevent deficiencies that, over time, can cause harm in ways that we are just beginning to understand."
To supplement or not?
If we are malnourished by the food we eat, should we be taking vitamin and mineral supplements to ensure that we maintain health? And if we do so, are we causing more harm than good and even hastening our own death?
The studies that suggest supplements can be killers have been strongly criticized by pro-vitamin groups who dismiss them as 'bad science', yet their findings-while flawed-highlight the subject's complexities.
According to Dr Robert Verkerk, director of the ANH, the following needs to be taken into consideration when supplementing:
- Isolated nutrients. The damning studies have con-centrated on people taking individual, and synthetic, vitamins, and especially carotenoids (vitamin A) and vitamin E. Researchers are finding that supplements that mirror the process by which we absorb vitamins from our foods are the most effective and the safest to take. Therefore, complex supplements that act synergistically appear to be safer and more beneficial.
- Antioxidants. The standard antioxidants-beta-carotene, vitamins A, C and E, and selenium-can have the reverse effect, and become pro-oxidants if they are taken individually and at too-high doses. High doses of synthetic vitamin E reduce the body's absorption of the more important antioxidant form of vitamin E, gamma-tocopherol, which is the type that is found in foods and in high-quality supplements.
- Synthetic forms. Synthe-sized forms of vitamin E (alpha-tocopherol), beta-carotene and folic acid (pteroylmonoglutamic acid)-taken individually-can have a harmful effect in some individuals. However, these supplements are safe-and beneficial-if taken in the following forms: vitamin E as mixed tocopherols and tocotrienols; beta-carotene as mixed natural carotenoids; and folic acid as natural folate, including the 5-methyltetrahydrofolate form.
Anti-caking agents-used in powdered forms of vitamins and especially vitamin C-are failing to protect the nutrient from moisture damage, even at relatively low temperatures and levels of humidity. As a result, many people may be getting little or no nutritional value from such supplements. Worse, once the process of degradation has started, the product changes rapidly from a solid to a liquid state and becomes unstable, possibly causing health problems (J Food Sci, 2011; 76: C1062-74).
Not many dead
When these issues are taken into account, the so-called 'killer effects' of supplements identified by a small handful of studies become questionable. The Iowa Women's Health Study relied on information collated from questionnaires completed by 38,772 women, but failed to ask the women the dosages and types of vitamin supplements they were taking. The 'dangerous' vitamin supplements included B6 and folic acid, and the minerals iron and copper, the researchers said.
As well as failing to note the type of supplements being taken, they also did not ask the women if they were also taking pharmaceutical drugs, or about their nutritional status and whether they already had subclinical signs of a chronic disease that supplements would not have helped to reverse.
The Cochrane review, published three years earlier, discovered that 13.1 per cent of the 232,550 participants taking an antioxidant supplement-whether vitamin A, C or E-died compared to 10.5 per cent of deaths in the non-supplement group. However, before arriving at the trials included in the review, the Cochrane researchers dismissed 405 other studies of vitamin supplements that did not have any deaths, thereby weighting the results before-hand. The 67 trials selected for the meta-analysis included only those that tracked people who were already chronically sick-and so more likely to die-and who were taking high-dose supplements. This, as the ANH pointed out, was not a fair reflection of the average supple-ment use.
The bottom line
In their concluding remarks, the Cochrane researchers say their findings support the drive to have vitamin use more carefully controlled and restricted.
A sceptic may argue that their recommendation reveals their true hand, and it's an accusation that has been laid at the door of other researchers who have concluded that vitamin supplements are killers.
Their findings certainly provide 'evidence' to feed the drive-throughout Europe and, more recently, in the US-to restrict supplement availability, but this handful of studies stands out starkly against the thousands that have demonstrated genuine, and therapeutic, benefit from supple-ments (see box, page 13). Their other findings are also out of step, which is another clue that there is something wrong in their analysis and/or interpretation.
Factfile A: House rules for good health
For the consumer, maintaining health is relatively straight-forward, provided you follow some simple house rules:
- Choose your food supplier with care-you want to eat organic and locally sourced foods. Even organic food will not be as fresh and nutritious if it's sourced from overseas.
- Grow your own food if possible. That is about the only way you can guarantee the nutritious value of your food, as even organic food can come from depleted soil.
- Assume that you are depleted in magnesium and zinc-most people are, so include these minerals in your daily supplement regime. You are probably also depleted in vitamin D, so supplement or get it from your diet by eating fatty fish, liver and dairy.
- Eat much more than the five-a-day recommendation of fruits and vegetables. RDI levels were created as the minimal requirement to avoid malnourishment, and not to achieve optimum health. Even so, do not overdose on vitamins E and A, as high levels can be toxic.
- Choose your vitamins with the same care you exercise in selecting your food supplier. Take complex vitamins that act synergistically-the closer that vitamins mirror the way food delivers vitamins and minerals, the better.
- Don't believe the bad press-mineral and vitamin supplements play an important role in helping to overcome chronic conditions, provided you follow the house rules by selecting the best forms.
Factfile B: Your daily lack
The following are the Reference Daily Intakes (RDIs) for the main vitamin and mineral groups. These are the minimum requirement to avoid deficiencies, and are not the levels required for maintaining good health. Amounts for those marked with an asterisk (*) need to be increased dramatically beyond the RDI.
|Vitamin A||5000 IU|
|*Vitamin C||60 mg|
|*Vitamin D ||400 IU|
|Vitamin E||30 IU|
|*Vitamin K ||80 mcg|
|*Vitamin B6||2 mg|
|*Vitamin B12||6 mcg|
Factfile C: Supplements help, not kill
The handful of studies that suggest supplements shorten life fly in the face of the thousands that, over the years, have demonstrated that supplements prevent-and even help to reverse-serious health problems.
- ALS (amyotrophic lateral sclerosis). As so often happens when investigating supplement use, researchers from the Harvard School of Public Health set out to establish that vitamins cause disease-and discovered the very opposite. In a study of 805 ALS sufferers, the researchers found that vitamin E supplements helped to prevent the disease, especially in women (Am J Epidemiol, 2011; 173: 595-602).
- Cancer. Taking multivitamins and minerals every day can help to prevent cancer. In a meta-analysis of supplement studies, researchers concluded that vitamin supplements may prevent cancer in people with poor nutritional status (Evid Rep Technol Assess, 2006; 139: 1-117).
- Cervical cancer. Vitamins A (including beta-carotene), C and E are powerful protective agents against cervical cancer, say researchers who tracked 144 patients and 288 age-matched healthy controls (Nutr Cancer, 2010; 62: 181-9).
- Colon cancer. Eating more vegetables, fruit and wholegrain products did not reduce the risk of colon cancer, but taking vitamin and mineral supplements for five years or longer did. The effect was significant, particularly in women, say the researchers (Eur J Cancer Prev, 2007; 16: 275-91).
- Infection. Nutritional supplements help to prevent infections, especially in people who have type 2 diabetes. A total of 196 diabetics were given either micronutrients or a placebo for six months. Incidences of upper respiratory tract infections (the common cold), whitlow (abscess in the tissues around the nails), vaginitis, urinary tract infections, gingivitis and dental ulcers were all lower in the group given the nutrients (Asia Pac J Clin Nutr, 2011; 20: 375-82).
- Inflammation. Vitamins C and E, and carotene, work in combination to reduce C-reactive protein and homocysteine in the blood, both of which are markers of inflammation, a recognized major cause of more than 80 diseases, including heart problems (Public Health Nutr, 2011; 14: 2055-64).
- Longevity. Even standard doses of vitamin D supplements can help us to live longer. D2 (ergocalciferol) and D3 (cholecalciferol) have protective effects against life-threatening diseases such as cancer, cardiovascular disease and diabetes, and so help to increase longevity, say researchers (Arch Intern Med, 2007; 167: 1730-7).
- Mental health. Vitamin D supplements help us stay mentally sharp as we age. One study of 5596 women with an average age of 80 years reported that weekly vitamin D supplements helped to improve memory and concentration (Neurology, 2010; 75: 1810-6).
- Myocardial infarction (heart attack). Vitamins A, C, D and E halve the risk of myocardial infarcts if taken individually. The protective effect is strongest in women
- who have no history of heart disease. A multivitamin taken for five years or more is also protective (Am J Clin Nutr, 2010; 92: 1251-6).
- Osteoporosis. Vitamins D and K help to improve bone health in postmenopausal women. In the study, 51 women-all of whom were at risk of developing osteoporosis-were put on a Mediterranean-style, low-glycaemic diet and a regimen of aerobic exercise, and were also given vitamins D and K or a placebo. There was a significant increase in collagen-and more favourable markers of bone metabolism-in the vitamin group compared with the placebo controls (Nutr Res, 2011; 31: 347-55).
- Pregnancy. Women who take vitamin C or ascorbic acid reduce their chances of needing hospital care during pregnancy. In a study of 384 pregnant women, half were
- given 400 mg of vitamin C every day; 42 per cent of these women-compared with only 27 per cent in the non-vitamin group-did not need hospital care (Pan Afr Med J, 2011; 5: 15).
- Prostate cancer. Zinc supplements protect against prostate cancer. In a study of 35,242 men, those who took an average of 15 mg/day or more of the supplement were much less likely to develop the disease than those who did not supplement (Nutr Cancer, 2009; 61: 206-15).
- Wound-healing. Taking vitamin C with zinc orally helps to speed up the healing of wounds. The combination works better for healing ulcers and surgical wounds than just taking vitamin C on its own (Curr Opin Clin Nutr Metab Care, 2009; 12: 588-95).
WDDTY ISSUE 22 NO.9, NOV. 2011