The Study
Marine Omega-3 Fatty Acids and Prevention of Vascular Disease and Cancer
This study gave people fish oil pills or fake pills and watched what happened over five years. It didn't find that fish oil stopped heart attacks or cancer in most people, but it also didn't prove it does nothing at all — just that if it helps, the help is very small.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists gave older adults daily fish oil pills or dummy pills for over 5 years to see if they stayed healthier.
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 574 / 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.
- 1For most people, fish oil pills didn't make a big difference in preventing major diseases, but they might help a little with heart attacks — though we can't be sure yet.
- 2Fish oil didn't stop major heart problems or cancer.
- 3But it was linked to 28% fewer heart attacks and 22% fewer heart procedures — but these weren't the main goals of the study.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
The New England journal of medicine
Year
2018
Authors
J. Manson, N. Cook, I. Lee, W. Christen, S. Bassuk, S. Mora, H. Gibson, C. Albert, D. Gordon, T. Copeland, Denise D’Agostino, G. Friedenberg, Claire Ridge, V. Bubes, E. Giovannucci, W. Willett, J. Buring
Related Content
Claims (6)
Taking a daily omega-3 supplement for about five years might lower the chance that healthy adults over 50 will need a heart procedure to open a blocked artery, but it’s not clear if the supplement directly caused this benefit.
Taking a daily omega-3 supplement for about five years doesn't seem to lower the risk of heart attacks, strokes, or heart-related death in healthy people over 50.
Taking a daily omega-3 supplement for over five years doesn't seem to lower the risk of getting any kind of invasive cancer in healthy people over 50, according to a big study.
Taking a daily omega-3 supplement for about five years might lower the chance of having a heart attack in people over 50 who are otherwise healthy, but scientists aren't totally sure yet and need to check this again.
Taking fish oil supplements every day might lower your chances of having a heart attack, but it won't make a big difference in preventing other serious heart problems or getting cancer if you're a healthy older adult.
For people over 50 who don’t eat much fish, taking a daily omega-3 supplement for about five years might help lower the risk of serious heart problems, but the evidence isn’t strong enough to be sure.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.