Review · Cureus · 2025Conflicts declared

Alpha-tocopherol supplements: benefits and risks in adults

What it found

High-dose alpha-tocopherol supplements are linked to more deaths, heart failure, bleeding, and prostate cancer in some groups, while low doses may help.

The evidence comes from trials and meta-analyses in people, plus some animal and lab studies.

What they found

Studies in people

Death from any cause

A 2005 meta-analysis of 135,967 participants in 19 trials found that high-dose vitamin E (400 IU/day or more) was linked to a higher risk of death from any cause. The risk difference was 39 per 10,000 people. Doses above 150 IU/day were linked to increased risk.

Heart failure risk

In the HOPE and HOPE-TOO trials, vitamin E was an independent predictor of heart failure in people with vascular disease or diabetes. In the GISSI-Prevenzione trial, people who had a recent heart attack and had poor ventricular function had a 50% increased risk of heart failure.

Stroke risk

A 2010 meta-analysis of 118,765 people found that vitamin E increased the risk of hemorrhagic stroke by 22% and decreased the risk of ischemic stroke by 10%. The authors said the increase in hemorrhagic stroke outweighed the reduction in ischemic stroke.

Bleeding with blood thinners

In people taking warfarin, higher serum vitamin E levels were linked to more minor and major bleeding. Vitamin E also interferes with vitamin K-dependent clotting factors.

Animal and lab studies

Bone strength in rats

A Harvard study found that rats given mega-doses of vitamin E developed 20% weaker bones than rats on a normal diet. This effect has not been studied in humans.

Studies in people and animals

Prostate cancer risk

The SELECT trial, which followed 35,533 men, found a 17% increase in prostate cancer in men taking vitamin E alone compared to placebo. Lab studies with prostate cells suggest vitamin E may promote cell growth and survival.

What the authors conclude

“Overall, the findings in these studies strongly suggest that while low-dose Vitamin E supplementation may be beneficial, high-dose supplementation can pose serious risks to patients, especially those with a history of cardiovascular disease or stroke.”
Kaye AD, Thomassen AS, Mashaw SA, et al, 2025

Also in their conclusions

  • They conclude that low-dose vitamin E supplementation may be beneficial, but high-dose supplementation can pose serious risks, especially for patients with a history of cardiovascular disease or stroke.
  • They advise that vitamin E supplementation should be used cautiously in patients taking anticoagulant and antiplatelet drugs.
  • They recommend that most people should get vitamin E from a balanced diet, and that supplementation should only be started under a doctor's guidance.

How it was done

The authors wanted to clarify the balance between the claimed benefits of vitamin E supplements and growing evidence of harm at high doses.

They reviewed large trials and meta-analyses of vitamin E supplementation in adults, including the HOPE, GISSI-Prevenzione, and SELECT trials, plus animal and lab studies on how harm might occur.

What it can’t tell you

  • Most trials included older adults with existing health conditions, so the findings may not apply to healthy younger people.
  • Animal and lab studies can suggest how harm might happen, but they cannot show what happens in people.
  • The link between vitamin E and bleeding comes from studies that followed people over time, so they can show a link but not prove cause and effect.

The paper

Title
Vitamin E (α-Tocopherol): Emerging Clinical Role and Adverse Risks of Supplementation in Adults
Type
ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
Evidence
Studies in people · animals · lab
Summarised from
Full text
Cite
Kaye AD, Thomassen AS, Mashaw SA, et al (2025). Vitamin E (α-Tocopherol): Emerging Clinical Role and Adverse Risks of Supplementation in Adults. Cureus. doi:10.7759/cureus.78679Free full textPubMed 40065887DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error