How Omega-6s Usurped Omega-3s In US Diet
11 Sep 2006
Has a little-known family of polyunsaturated fatty acids called Omega-6s, which has quietly permeated the Western diet in recent decades, nullified the impact of heart disease-fighting omega-3s? According to a new book, The Queen of Fats, Americans now have so many omega-6s in our bodies that eating fish to bolster our omega-3s may not do any good. Why? Because these two families of fats compete in our body's metabolism.
Or, as Susan Allport, the author of this new landmark book about the history, science and economics of omega-3s, published by the University of California Press (September, 2006), puts it: “It is not the fish we are NOT eating that is our problem, but the oils we ARE eating.”
How have omega-6s saturated the Western diet so completely and quietly? Ms. Allport's heavily researched, fact filled book says that most of our cooking oils are heavily laden with omega-6s (much used corn oil, for example, has a 46 to 1 ratio of omega-6s to omega-3s; lesser used canola oil's ratio, however, is only 2 to 1), and that whatever omega-3s there are in oils are eliminated if those oils are hydrogenated or partially hydrogenated to extend the shelf life of foods, as occurs in most food manufacturing.
Also, when farmers feed corn and soybeans (instead of grass) to the animals we eat, their tissues become full of omega-6s at the expense of omega-3s. Eggs from chickens fed corn, for instance, have one-tenth the omega-3s in them as eggs from free-range chickens that eat greens and bugs.
According to Ms. Allport's research, the out-of-kilter balance between these two families of fats, one of which is derived from the fats in green leaves (omega-3s) and the other from seeds (omega-6s), is as much a culprit as cholesterol, saturated and trans fats for our country's epidemics of heart disease, obesity and other chronic health problems. Omega-6s are not bad, she cautions; in fact they are absolutely essential for health. We just have too many of them.
Ms. Allport writes at a lively pace about how scientists, in just the past two decades, have discovered how omega-3s are essential for our eyes to see and our brains to function, and she also focuses on policy changes that are needed. For example, most people are unaware of the omega-6/omega-3 problem because the USDA's dietary guidelines do not mention it. The American Heart Association does not distinguish between these two families of fats.
Short of overhauling some aspects of the food processing and vegetable oil industries, which she feels ultimately are necessary, Ms. Allport suggests we should consume oils and fats that have a healthier balance of omega-3s and omega-6s and eat foods that are rich in omega-3s, including greens, flax seed, fish, and free range (or omega-3 enriched) meat, dairy products, and eggs. She has a handy time line of the important omega-3 discoveries (from their use in brain function to prevention of arrhythmia), 30 pages of medical and science journal citations, interviews with researchers and a handy glossary of terms.
Article URL: http://www.medicalnewstoday.com/medicalnews.php?newsid=51575