You can find lots of diet advice to balance your omega 6 fatty acid consumption with omega 3 fatty acids. The thinking is that omega 6 fatty acids increase inflammation and therefore cause heart disease and other health problems. However, an advisory published in Circulation: Journal of the American Heart Association argues that a higher omega 6 fatty acid diet will lower heart risk when omega 6 fatty acids replace saturated fats in the diet.
Linoleic acid (LA) is the main omega-6 fatty acid in foods, accounting for 85 percent to 90 percent of the dietary omega-6 PUFA.
There has been some debate within the nutrition community regarding the benefits of omega-6 based on the belief that they may promote inflammation, thus increasing cardiovascular risk. “That idea is based more on assumptions and extrapolations than on hard data,” said Harris, a research professor for the Sanford School of Medicine at the University of South Dakota and director of the Metabolism and Nutrition Research Center at Sanford Research/USD.
This advisory questions the belief that omega-6 fats increase inflammation.
The linking of omega-6 intake to inflammation stems from the fact that arachidonic acid (AA), which can be formed from LA, is involved in the early stages of inflammation. However, the advisory explains that AA and LA also give rise to anti-inflammatory molecules.
For example, in the cells that form the lining of blood vessels, omega-6 PUFA have anti-inflammatory properties, suppressing the production of adhesion molecules, chemokines and interleukins — all of which are key mediators of the atherosclerotic process. “Thus, it is incorrect to view the omega-6 fatty acids as ‘pro-inflammatory,’” Harris explained. “Eating less LA will not lower tissue levels of AA (the usual rationale for reducing LA intakes) because the body tightly regulates the synthesis of AA from LA.”
A meta-analysis of several trials finds that omega 6 polyunsaturated fatty acids (PUFAs) cut heart risks by a quarter.
In controlled trials in which researchers randomly assigned people to consume diets containing high versus low levels of omega-6 and then recorded the number of heart attacks over several years, those assigned to the higher omega-6 diets had less heart disease.
A meta-analysis of several trials indicated that replacing saturated fats with PUFA lowered risk for heart disease events by 24 percent. “When saturated fat in the diet is replaced by omega-6 PUFA, the blood cholesterol levels go down,” Harris said. “This may be part of the reason why higher omega-6 diets are heart-healthy.”
But would a diet where monounsaturated fats displaced the PUFAs cut heart risk even further?
Getting omega 3 fatty acids in your diet is still a good idea. Also, how you get your omega 6 fatty acids probably matters. For example, Nuts which are high in omega 6 also contain magnesium, vitamin E, and other beneficial nutrients. Whereas cooking oil delivers the omega 6 fats without as much of other nutrients.
|Share |||Randall Parker, 2009 January 27 10:53 PM Aging Diet Heart Studies|