Two new studies demonstrate the shaky underpinnings of guidelines that
encourage the intake of omega-3 fatty acids.
The first, a large meta-analysis in the Annals of Internal Medicine,
examined dietary fatty acid consumption, fatty acid biomarkers, and
fatty acid supplements. Among the chief findings:
Omega-3 and omega-6 fatty acids: There were trends for modest benefits
associated with dietary intake or supplements, but these did not
achieve statistical significance.
Saturated fatty acids: There was no discernible effect of total
saturated fat as measured by either dietary intake or circulating
Monounsaturated fatty acids: No effect was found.
Trans dietary fats: A harmful effect was confirmed.
In the second study, published in JAMA Internal Medicine, 4200
patients with age-related macular degeneration were randomized to
omega-3 fatty acids; lutein/zeaxanthin (carotenoids found in the eye);
both; or placebo. After roughly 5 years, there was no significant
reduction in cardiovascular outcomes in the treatment groups.
Commentators say it’s now clear that omega-3 supplements “with daily
doses close to 1 g in patients with or without established CVD shows
no clear, considerable benefit.” They conclude that for now, omega-3s
should be prescribed only for patients with severe
hypertriglyceridemia, “an extreme minority of the general population.”