Health, psychology & science stories
Integrity of vitamin & mineral supplements
8 January 2002
Published in The Age
Vitamin and mineral supplements have become a part of our national health landscape since the 1970s. According to 1995’s National Nutrition Survey, vitamins B and C are particularly popular among Australians, followed by multivitamin formulas, and a host of less famous nutrients.
Despite their popularity, there are two widely divergent schools of thought on supplements. Conservative medicos regard them as a con to extract money from those insecure about the purity of the food supply. But other health professionals claim that supplements provide real nutrition, and even improve or cure certain ailments.
The doyenne of Australia's nutritionists, Rosemary Stanton, is one of the “conservatives”.
"In most cases, if your diet is so poor that you need to add supplements, you should first fix your diet," Stanton says.
"The idea that foods no longer provide nutrients is simply not true. In most countries, government departments and many universities analyse foods - and they find the nutrients still present in vegetables, fruits, nuts, seeds, grains, fish, meat and other fresh foods."
In addition, Stanton points to a problem which lurks at the back of many consumers' minds:
"Initial results of IOC-sponsored tests on over-the-counter nutritional supplements revealed that of 200 products tested, 20% contained banned substances, such as [the anabolic steroid] Nandrolone," she said.
The incidence of banned substances in over-the-counter supplements "is much higher than we though it would be," said the chief of the IOC medical commission, Patrick Schamasch. When the IOC’s statement was put on the NSW Institute of Sport website in November, it sent shockwaves through the Australian health industry.
However Vicki Katernick of the Australian Sports Drug Agency pours cold water on the alarm:
“We simply aren’t having the same problem in Australia. When athletes test positive here, they’re not blaming supplements. I think you can put that down to the fact that the labelling requirements in Australia are a deal more stringent than they are in the US.
“Where the problems might occur here, we think, are where athletes are buying things over the Internet from overseas.”
In vitamins made here by leading Australian manufacturers, banned substances, Katernick says, “are not an issue”.
A more real problem with supplements is the out-and-out scams.
The progenitor of colloidal minerals, the American rancher Thomas Jefferson Clark, gained their secrets from Chief Soaring Eagle of the Paiute Indians in the 1930s. Or so the promotional materials tell us.
Curiously, the modern-day Paiute have never heard of Clark. They've never heard of Chief Soaring Eagle either.
A world authority on colloidal minerals, geochemist James Pontolillo, says claims about their health benefits "are pseudoscientific gibberish".
“Colloidal mineral supplements,” Pontolillo told The Age, “are like many other nutritional supplements - long on wild claims and short on hard evidence. They are an untested, unregulated and potentially harmful product that purports to address a non-existent ill. The only positive benefits that accrue from their use is the fattening of a distributor's bank account. It never ceases to amaze me how people who are suspicious of doctors and pharmaceuticals, both of which are stringently if imperfectly regulated, can also be quite willing to ingest a mysterious substance being sold to them by a modern-day huckster.”
Pontolillo’s “non-existent ill” is mineral deficiency: “And specifically the promoter's typical claim that mineral deficiencies cause virtually every health malady known to man.”
If colloidals lack scientific support, other nutrients are showing more promise.
Indeed a major research development in recent decades is the use of specific nutrients as drugs. Sometimes this is in the form of large doses, or “megavitamins”. The practice overall is sometimes called “orthomolecular medicine”. It began in the 1950s, when Drs Hoffer and Osmond conducted ground-breaking double-blind trials on the use of vitamin B3 against schizophrenia.
These studies, the still-active 83-year-old Dr Abram Hoffer told The Age from Canada, proved that vitamin B3 “doubled the two year recovery rate of acute schizophrenics”.
The American Psychiatric Association believes that “the credibility of the megavitamin proponents is low" - though this may be a bit rich, coming from a profession oft-perceived to be in the pocket of the drug industry.
And other studies of vitamin therapy have produced equally impressive results.
In a study of 4,000 parents of autistic children, six times as many observed behavioural improvements in their children from vitamin B6 and magnesium supplements as did from the popular drug thioridazine.
"When supplemented before conception, iodine prevents cretinism and folic acid reduces neural tube defect risks" such as spina bifida, the US Department of Health and Human Services has announced.
Double-blind studies have suggested that magnesium can reduce systolic blood pressure; that critically ill patients given the amino acid glutamine recover more frequently; and that calcium and vitamin D supplementation reduces bone loss and fracturing in older people. Long-term selenium supplementation seems to reduce cancer deaths dramatically.
A small US controlled study has found that children with learning disabilities improved markedly in both school grades and behaviour after consuming nutrient supplements.
Unhappily, riding on the coat-tails of every such success story are half a dozen fraudulent claims: that zinc improves the symptoms of genital herpes, that shark cartilage is useful against cancer, that vitamin B6 works against PMS. And that colloidal minerals cure baldness.
Then there are the trial failures. In large prospective overseas studies, vitamins C and E (in both diet and supplements) did not protect against breast or bowel cancer: vitamin A may even have increased the risk of contracting cancer.
And when assessing a nutrient’s value, it’s important to distinguish food intake from supplement intake. For example, a US study found that vitamin E helps protect against death from coronary disease in post-menopausal women. However the women who obtained the vitamin from their diets were better-protected than the supplement-takers.
Finally, there are the nutrients which may be downright dangerous. A 1993 study of 23,000 pregnant women in the New England Journal of Medicine found:
"Among the babies born to women who took more than 10,000 IU of preformed vitamin A per day in the form of supplements, we estimate that about 1 infant in 57 had a malformation attributable to the supplement."
Smokers who take vitamin A with beta carotene may be more susceptible to lung cancer.
Unhappily, consumers can’t expect any agreement among the “experts” on supplements: there’s anything but a global consensus. The health guidelines of Australia’s National Health and Medical Research Council don’t even mention them.
Complicating matters, one wave of researchers has an uncanny knack of overturning what seemed like the watertight conclusions of its predecessors. And whilst a few major studies are very well-known, hundreds of equally important studies are unknown even to most health professionals.
For the moment, Australians are mostly interested in taking their “maintenance doses” of vitamins B and C, and multivitamin formulas.
But as alternative medicine swallows an increasing proportion of the nation’s health dollar, the practice of treating specific illnesses with nutrient supplements is likely to spread.
This can only benefit consumers if alternative therapists are fearless in embracing scientific method, reluctant to use unproven therapies, and ruthless in throwing out those vitamin and mineral supplements which are proven to be either dangerous or ineffectual.
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