Nutritionists and food information experts think half of the Western population is crazy. That's how many take nutritional supplements according to recent surveys. And all for nothing. Worse still, supplements only make you more unhealthy, say scientists and information providers.
According to an American study that was recently published in the American Journal of Clinical Nutrition, the value of nutritional supplements is questionable. In the study, researchers followed 78,000 people aged between 50 and 76 for a period of 5 years. The researchers had information on the subjects' supplements use over the previous 10 years and assessed whether supplements reduced mortality or increased it.
The table below shows the effect of a number of separate vitamins on mortality. None of the trends shown is statistically significant, although nearly all vitamins appear to lower the chance of mortality. Highest score goes to the odious beta-carotene. [If you smoke or work with asbestos, you're still better off avoiding this supplement.]
When it comes to the minerals, magnesium scores best. For the minerals there is no statistically significant trend to be seen either, although once again all seem to reduce mortality.
There are stronger causal relationships in the non-vitamin/non-mineral supplements category. Glucosamine and chondroitin reduce mortality significantly. Fish oil lowers mortality by an almost significant amount, and ginkgo is not far off a statistically significant effect too. That the researchers actually managed to find something approaching a relationship for ginkgo is pretty miraculous: there are ridiculous amounts of under-dosed ginkgo supplements on the market.
The researchers come up with a theory, based on a literature search, on the possible mechanism behind the life-extending effect of glucosamine and chondroitin. Studies suggest that glucosamine and chondroitin protect the blood vessels and reduce the chance of developing lung and bowel cancer.