Most dietary supplements are not even worth considering

The worldwide market for health and nutrition supplements and vitamins is truly huge. Americans alone spend about $30 billion a year on vitamins, minerals and herbal products (that's about $100 for every man, woman and child). This is partly the result of a 1990s law change that allows products to be sold to "support" the health of the body or various body parts, even if no claims are made for the prevention, treatment or cure of any particular ailment.

Millions of people swear by their daily regime of vitamins and minerals. But do we actually know whether the most popular health supplements are actually effective? Are they, in reality, anything more than placebos or just wishful thinking?

One article by a scientific journalist in the New York Times recently tackled just that problem, and his conclusions were disquieting at best. Among his findings:

• Multivitamins - studies by a number of major health institutions and charities have concluded that a daily multivitamin does little or nothing to fend off chronic illnesses like cancer or heart disease, and a sensible balanced diet is likely to be much more effective.
• Vitamin D - most people these days are deficient in vitamin D, which helps the body absorb the calcium and phosphorus we need to maintain strong bones, and so this may be one of the few supplements that are actually worthwhile, particularly for older people, even if it has not been shown to actually prevent bone fractures.
• Calcium - many people are also deficient in calcium, but a better diet with more dairy products, dark green leafy vegetables, tofu, fortified breakfast foods, etc, would be a better solution than supplements, which can often cause constipation, and has been associated with an increased risk of heart attacks, kidney stones and gastrointestinal problems.
• Vitamin B12 - many people, particularly older people, are deficient in this vitamin, which is needed for healthy brain and muscle function, even those who eat meat (the main source of B12), and a supplement may be necessary over and above what can be found in fortified food sources.
• Fish oil - variously promoted as a miracle cure for heart disease, cognitive decline and much more, fish oil has actually not been found to be efficacious in studies, and may even increase the risks of an aggressive form of prostrate cancer.
• Magnesium - studies have not borne out claims that magnesium can help prevent leg cramps, and, while it may help with constipation, it also brings with it a risk of diarrhoea and of interference with the functioning of antibiotics and other medications.
• Turmeric - used in traditional Chinese and ayurvedic medicine, turmeric does have some anti-inflammatory, anti-diuretic and even anti-cancer properties (although official scientific evidence is rather thin on the ground), and anecdotally it can help with some inflammatory conditions like plantar fasciitis.
• Glucosamine/Chondroitin - studies have shown that the supplement's much-touted efficacy against arthritis are completely unfounded, and it has no more effect than a placebo.
• Vitamin E - once thought to lower the risk of prostrate cancer, studies have shown that those taking vitamin E supplements actually developed significantly more cancers than those on a placebo.
• Selenium - also widely taken to lower the risk of prostrate cancer, selenium supplements have been shown in studies to substantially increase the incidence of diabetes.

Hmmm. All in all, it seems like a much better idea to spend some money on improving our diets than investing in dietary supplements. The only supplements that might be worth considering are vitamin D and B12.