Friday, April 8, 2011

Sense on Omega Fats Balance

One of the major differences between our post-industrial diets and the evolutionary and traditional foods of our past is in the kinds of fat we eat. One huge change has to do with the polyunsaturated fatty acids (or PUFAs), which come in several varieties, but most commonly omega 6 and omega 3. PUFAs are "essential fats," meaning we can't make them from other types of food, and we must eat them. However, never in the history of humankind have we eaten novel omega 6 fatty acids in such massive quantities.

Corn oil, safflower oil, sunflower oil, cottonseed oil, peanut oil and/or soybean oil are ingredients in pretty much all processed food. Just check the list on the back of breakfast cereals, bread and other baked goods, fried items, salad dressings, margarine, mayonnaise, and sauces. Vegetable oils are used (along with canola oil) in the fryers at most restaurants. They are cheap and relatively tasteless, which make them perfect for certain industrial and restaurant food applications. They are also universally high in omega 6 fatty acids, and therefore we eat a ton of them in the Western diet, especially since throwing out butter, lard, and beef tallow 30-40 years ago.

Why does it matter if we eat lots of vegetable oil? Omega 6 PUFAs are used by the body to make certain hormones and signaling molecules. Roughly speaking, the omega 6s are the precursors for many of the molecules that make up our body's inflammatory response. As an example - the omega 6 linoleic acid (corn oil is mostly linoleic acid) is a precursor for many molecules, but among them are the prostaglandins that the enzymes COX-1 and COX-2 work on. If you have ever taken ibuprofen or another NSAID painkiller, you have blocked the effects of COX-1 and COX-2, decreasing inflammation and therefore the easing experience of swelling and pain in the body
Here's the real problem - too much inflammation mediated by a high dietary percentage of the omega 6 fatty acid linoleic acid can be reasonably associated with coronary vascular diseaseinsulin resistancecancer, hypothyroidism and other autoimmune diseases, thrombotic stroke, headaches, asthma, arthritis, depression, and psychosis

This papernotes that "it is intriguing that the dramatic increase in the prevalence of [Alzheimer's disease] in the last century not only parallels the increase in average lifespan, but also an increase from 2 to more than 20 of the ratio of omega 6 to omega 3 PUFAs in the average Western diet."

...common sense will tell us that the best result would likely result from decreasing the overall omega 6 burden while making sure we get adequate omega 3s of the right kind for our brain.
In simple terms, that means significantly decreasing the amount of processed food we eat, and making sure we get some oily fish a few times a week. Switching to grass-fed beef and eating lamb or bison (which are usually grass fed) will also help. Olive oil is relatively low in omega 6 (it is primarily a monounsaturated fat and therefore a neutral player in the inflammatory vs. anti-inflammatory war), so olive oil and vinegar or lemon juice can be deliciously substituted for commercial salad dressings. For baking and cooking, use butter, lard (a commenter reminds me it should be naturally sourced and used in moderation, of course), or coconut oil! It won't kill you. Really.

No comments:

Post a Comment