Friday, November 12, 2004

Vitamin E - Safe or Not?

If you read the health file in the newspapers, you have probably seen the articles talking about new studies on the safety of Vitamin E and how taking it can increase your risk of premature death.

Something they fail to mention is that this new information comes as the result of a meta-analysis. A meta-analysis is a statistical technique where they combine the results of numerous studies to reach a conclusion. If done correctly, it can be a useful tool. However, its usefulness in this case is highly doubtful. Why? Because they combined the data of trials with natural forms of Vitamin E with synthetic forms of vitamin E.

Some synthetic forms of vitamins are comparable to their natural counterparts. This is not true of Vitamin E. In nature, Vitamin E occurs as eight compounds known as tocopherals (alpha, beta, delta, gamma) and the tocotrieonols (alpha, beta, delta, and gamma). Synthetic E has only the alpha tocopherol. Many studies show a benefit when giving the natural and complete form of Vitamin E, but studies that utilize the synthetic form show a health detriment, and many large clinical trials use synthetic forms, for reasons that are beyond me.

Now, do you see how combining studies where natural forms of the vitamin are used with studies that use synthetic forms can skew the results? A good scientist tries to remove all biases from the study in order to give an accurate result. One has to ask why there was a failure to separate out studies that used natural as opposed to synthetic forms.

Whenever natural food products and supplements come under fire, I tend to be suspicious and want to start digging. If you want to know why, read here.

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