Q: How much over the RDA would be wise and safe in taking vitamin E for arthritis and premenstrual syndrome?
– Sue in Berkeley, CA

A: Vitamin E is a relatively safe vitamin and can be taken in doses as high as 800IU or more with little or no adverse side effects. The only concern is if you also take blood-thinning medications, since vitamin E also is a blood thinner and could cause excessive bleeding if taken with these medications. Typical recommendations for vitamin E are 100IU to 400IU a day. Whether vitamin E is effective in the treatment of either arthritis or Premenstrual syndrome has not been proven, so taking doses any greater than 400IU for these conditions is not recommended without physician approval. – Elizabeth Somer