Researchers at the University of California, San Diego School of Medicine have discovered why eating fish may be a great idea to ward off chronic inflammation and insulin resistance.
Jerrold Olefsky and colleagues identified a key receptor on macrophages abundantly found in obese body fat. Obesity and diabetes are closely correlated. The scientists say omega-3 fatty acids activate this macrophage receptor, resulting in broad anti-inflammatory effects and improved systemic insulin sensitivity.
Obese fat tissue contains lots of these macrophages producing lots of cytokines, which cause inflammation and rising insulin resistance.
Olefsky and colleagues eventually narrowed their focus to a G-protein receptor called GPR120, which is found only on pro-inflammatory macrophages in mature fat cells. When the receptor is exposed to omega-3 fatty acids, it is activated and generates a strong anti-inflammatory effect.
"The omega-3 fatty acids switch on the receptor, killing the inflammatory response," said Olefsky
"Our work shows how fish oils safely do this, and suggests a possible way to treating the serious problems of inflammation in obesity and in conditions like diabetes, cancer and cardiovascular disease through simple dietary supplementation," he added.
However, it's not clear how much fish oil constitutes a safe, effective dose. If too high, it could up the risk of to increased risk of bleeding and stroke in some people.
The study is published in the September 3 issue of the journal Cell.