Too Much Omega-6 Compared to Omega-3 May Raise Obesity Risk

This review looks at how the balance between omega-6 and omega-3 fatty acids in our diets has changed dramatically over the past century. During human evolution, people consumed roughly equal amounts of omega-6 and omega-3 fats (a ratio near 1:1), but modern Western diets now have ratios as high as 20:1 or more, mainly due to increased vegetable oil consumption and changes in how animals are raised and fed.

The author explains that omega-6 and omega-3 fats are processed differently in the body and produce different signaling molecules that affect fat cell formation, inflammation, and metabolism. Diets heavy in omega-6 relative to omega-3 tend to promote a more inflammatory, fat-storing physiological state, while better omega-3 intake appears linked to lower body fat markers in blood tests across several population studies.

The review also discusses genetic differences between population groups in how efficiently they convert plant-based omega-6 and omega-3 fats into their more active long-chain forms, which may partly explain why some groups show higher obesity-related risks. It notes that clinical trials testing omega-3 supplements for weight management have had mixed results, likely due to differences in study design, background diet, and how omega-3 status was measured.