The Study
Vitamin E and C supplementation and risk of cancer in men: posttrial follow-up in the Physicians' Health Study II randomized trial.
This study is like a super careful experiment where half the guys took vitamin pills and half took sugar pills, and no one knew who got what. After many years, they checked who got cancer and found no difference. So we can say these vitamins didn't change cancer risk in these men.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists gave older male doctors either vitamin E, vitamin C, or fake pills for over 10 years to see if they helped prevent cancer.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 582 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1The difference was so tiny it could be due to chance — taking these vitamins didn’t meaningfully raise or lower cancer risk.
- 21,373 men got prostate cancer and 2,669 got any cancer — but the vitamin E and C groups had almost exactly the same number as the placebo groups.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
The American journal of clinical nutrition
Year
2014
Authors
Lu-Xuan Wang, H. Sesso, R. J. Glynn, W. Christen, V. Bubes, Joann E Manson, J. Buring, J. Gaziano
Related Content
Claims (6)
Taking 400 IU of synthetic vitamin E every other day and 500 mg of synthetic vitamin C every day for more than 10 years does not change the rate of cancer diagnosis in healthy male physicians aged 50 and older.
In one trial, vitamin E supplements did not show a link to cancer, but in another trial called SELECT, vitamin E supplements were linked to higher prostate cancer risk after long-term use. The difference between these results may be due to differences in who was studied, how much vitamin E was given, or how the studies were done.
Taking 400 IU of synthetic vitamin E every other day for 10 years does not raise the risk of prostate cancer in healthy men aged 50 and older, even when followed for longer than the trial period.
Taking 500 mg of synthetic vitamin C every day for over 10 years does not change how often healthy male physicians aged 50 and older develop total cancer or prostate cancer.
Taking vitamin E and vitamin C supplements does not change the risk of developing cancer in healthy male physicians, even when considering differences in age, smoking, weight, alcohol use, aspirin use, or family history of cancer.
Taking high doses of vitamin E supplements raises the number of prostate cancer cases in men without pre-existing cancer.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.