Systematic review · Nutrients · 2023Conflicts declared

Vitamin E and health outcomes across 32 meta-analyses

What it found

Vitamin E showed protective links with several health outcomes, but only the link between circulating alpha-tocopherol and asthma or wheeze in children had consistent evidence.

The authors say no firm general conclusion can be drawn about benefits.

What they found

Studies in people

Asthma or wheeze in children

The link between circulating alpha-tocopherol levels and asthma or wheeze in children was the only one supported by consistent evidence. However, this meta-analysis included observational studies, and both the GRADE and AMSTAR2 grades were very low.

Cancer and dietary vitamin E

Dietary vitamin E intake was linked to lower risk of several cancers, including lung, kidney, cervical, esophageal, and bladder cancer. Each 2 mg per day increase in dietary vitamin E was linked to a 5% lower risk of lung cancer.

Heart and blood vessel outcomes

Supplemental vitamin E improved endothelial function, reduced myocardial infarction and fatal myocardial infarction, and lowered systolic blood pressure. It also lowered serum CRP concentrations, but had no significant effect on IL-6, TNF-alpha, ApoA1, or ApoB.

Special populations

In hemodialysis patients, supplemental vitamin E may help ease oxidative stress and inflammation. In children, maternal vitamin E intake was linked to lower odds of asthmatic disorders, but supplemental vitamin E did not lower blood ALT in children with non-alcoholic fatty liver disease.

Nervous system

The link between supplemental vitamin E and Alzheimer's disease could not be determined due to follow-up issues and high heterogeneity. Vitamin E supplementation improved chemotherapy-induced peripheral neuropathy, but did not significantly lower stroke risk.

Other findings

Evidence quality

No health outcome was rated as having consistent evidence from supplemental vitamin E. Only 3 meta-analyses were classified as moderate quality, 7 as low quality, and 22 as critically low quality.

What the authors conclude

“In conclusion, our work has indicated that vitamin E is protective for several particular health outcomes. Further prospective studies are required when other factors that may contribute to bias are considered.”
Xiong Z, Liu L, Jian Z, et al, 2023

Also in their conclusions

  • They conclude that vitamin E is protective for several particular health outcomes.
  • They state that further prospective studies are required when other factors that may contribute to bias are considered.
  • They advise that no firm general conclusion can be drawn about benefits, and that better designed trials are needed for health outcomes with low quality of evidence.

How it was done

The relationship between vitamin E intake or circulating alpha-tocopherol and various health outcomes is still debatable and uncertain. The authors wanted to collect, summarize, and assess the quality and strength of the available evidence.

They merged and recalculated 32 meta-analyses covering 4 types of vitamin E sources and 64 unique health outcomes, from 409 randomized controlled trials and 268 observational studies. They classified the evidence into different levels based on statistical significance, heterogeneity, prediction intervals, and small study effects.

What it can’t tell you

  • Most of the links between vitamin E and health outcomes come from observational studies, which can show a link but cannot prove cause and effect.
  • The review could not accurately assess vitamin E intake from different sources because data on intake were not available.
  • Many of the included meta-analyses were rated as critically low quality, so the results should be interpreted with caution.

The paper

Title
Vitamin E and Multiple Health Outcomes: An Umbrella Review of Meta-Analyses
Type
Systematic review
Evidence
Studies in people
Summarised from
Full text
Cite
Xiong Z, Liu L, Jian Z, et al (2023). Vitamin E and Multiple Health Outcomes: An Umbrella Review of Meta-Analyses. Nutrients. doi:10.3390/nu15153301Free full textPubMed 37571239DOI

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