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Vitamin E — Frequently Asked Questions

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Frequently Asked Questions

Is vitamin E supplementation safe?

At the RDA of 15 mg (22 IU) daily, vitamin E is safe. However, a major meta-analysis found that high-dose supplements (≥400 IU/day) were associated with increased all-cause mortality. The SELECT trial also showed increased prostate cancer risk at 400 IU/day. Most experts recommend getting vitamin E from food (nuts, seeds, vegetable oils) rather than high-dose supplements.

What is the difference between natural and synthetic vitamin E?

Natural vitamin E (d-alpha-tocopherol) has approximately twice the bioactivity of synthetic vitamin E (dl-alpha-tocopherol). Natural forms are derived from plant oils, while synthetic is made from petroleum. On labels, "d-" prefix indicates natural and "dl-" indicates synthetic. When comparing IU amounts, you need twice as many IU of synthetic to match natural vitamin E's biological activity.

Should I take mixed tocopherols or just alpha-tocopherol?

Mixed tocopherols may be preferable because high-dose alpha-tocopherol alone can deplete gamma-tocopherol, which has unique anti-inflammatory properties. A mixed formula including alpha, gamma, delta, and beta tocopherols more closely mimics food-sourced vitamin E. If you choose to supplement, a low-dose mixed tocopherol formula (under 200 IU) with food is the safest approach.

Full Vitamin E Guide

References

  1. (). Meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality. Annals of Internal Medicine. DOI
  2. (). Vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). JAMA. DOI
  3. (). Vitamin E supplementation and in vivo immune response in healthy elderly subjects: a randomized controlled trial. JAMA. DOI
  4. (). Effect of vitamin E and memantine on functional decline in Alzheimer disease: the TEAM-AD VA cooperative randomized trial. JAMA. DOI