I've been taking a daily supplement of 400 IUs of Vitamin E. I recently bought a bottle of 1000 IUs, and a friend told me that that's too much to take, and could even be bad for me. Is that true?

Dear Reader,

Vitamin E, also known as alpha-tocopherol, is an antioxidant in the form of a fat-soluble vitamin. Your body's supply of fat-soluble vitamins, which also include vitamins A, D and K, accumulate and are stored in the liver and adipose (fat) and muscle tissues. In contrast, water-soluble vitamins such as vitamin C and the B vitamins are not stored but excreted regularly from the body. This means that you do not have to replenish your intake of fat-soluble vitamins as often as you do your water-soluble vitamins. Fat-soluble vitamins are also more easily absorbed by the body when consumed with some fat (the property that gives rise to the term 'fat soluble'). As with other vitamins, nutrients and minerals, it is often best to get your vitamin E by eating a varied and healthy diet rather than using supplements unless your doctor or other medical care provider specifically recommends otherwise.

The U.S. Recommended Dietary Allowance (RDA) for vitamin E in individuals 14 years or older is 22.5 IU (15mg). If a woman is breastfeeding, that requirement increases to 28.5 IU (19mg). There is no need to exceed the RDA level of intake unless you have been diagnosed with a vitamin E deficiency or another condition that would put you at risk for a deficiency. With those numbers in mind you may find that taking 1000 IU, or even 400 IU, of vitamin E daily over the long term can do some damage to your wallet (and possibly your body) without much benefit. Don't forget that the pills are not the only source of vitamin E going into your body; you will also be getting vitamin E through foods such as:

• almonds, peanuts, filberts
• wheat germ, cereal grains
• turnip greens, broccoli, spinach, leafy greens
• peaches, strawberries
• egg yolks
• milk fat
• liver
• sunflower and safflower oils

If you have been taking vitamin E supplements, you don't need to worry just yet; it does not appear to be harmful in large doses of up to 1500 IU per day over a short period of time. However, recent studies have shown that taking supplements of over 400 IU over the long term is associated with an increased risk of mortality (from all causes). The reason for this association is not clear and some of these studies have been criticized due to flaws in their designs, such as small sample size and use of subjects who were already sick. However, you might want to consider your reasons for taking vitamin E supplements before adding them to your routine over an extended period of time.

One of the potential dangers of long-term use is that high levels of vitamin E may increase one's risk of prolonged bleeding, especially for those who suffer from a vitamin K deficiency or those taking anti-coagulants (blood thinning agents) such as warfarin, heparin or aspirin. The body needs vitamin K in order to form blood clots. Taking high doses of vitamin E can greatly increase one's vitamin K requirement, which, for someone who already has a vitamin K deficiency, could put her/him at a greater risk for hemorrhaging. Vitamin E has not been found to produce blood-clotting abnormalities in individuals who are not vitamin K deficient.

Finally, as with any dietary supplement, the amount of vitamin E in each pill can vary greatly because the Food and Drug Administration (FDA) does not regulate nutritional supplements. That is, your 400 IU supplement may contain much more, or much less, vitamin E than what is listed on the label. After reading all of this, if you feel a vitamin E supplement is a good choice for you, it would be wise to speak with your health care provider about how much to take and how to find a reliable supplement brand.

Alice

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