The term essential fatty acids (EFA) refers to those polyunsaturated fatty acids that you have to get from your food because they cannot be synthesized in the body but are necessary for health. There are two families of EFA, omega-3 and omega-6. Omega-3 EFA’s are used to produce other fats that support eye and brain health and development. Omega-6 fatty acids lower harmful LDL cholesterol, boost HDL, and help keep blood sugar in check by improving the body’s sensitivity to insulin.
The good news is that a plant based diet has plenty of sources for both, so there’s no need to eat fish to get your omega-3 oils. For instance, flaxseed oil, walnuts, soybean oil and canola oil are good sources of omega-3s. Safflower oil, sunflower oil, corn oil, avocados and almonds are all good sources of omega-6s.
While there is a theory that omega-3 fatty acids are better for our health than omega-6 fatty acids, this is not supported by the latest evidence. Some people have incorrectly thought that the ratio of omega 3 to omega 6 fatty acids is important. However the omega-3 to omega-6 ratio is basically the “good divided by the good,” so it is of no value in evaluating diet quality or predicting disease. In the Health Professionals Follow-up Study, for example, the ratio of omega-6 to omega-3 fatty acids wasn’t linked with risk of heart disease because both of these were beneficial.
In a science advisory by the American Heart Association, nine independent researchers from around the country found that data from dozens of studies support the cardiovascular benefits of consuming omega-6 fatty acids. We need our omega-6s, which fortunately are abundant in a plant-based diet. Rather than cutting down on beneficial omega-6s, people would be better served by simply increasing their intake of omega-3 if they are concerned, by adding a handful of walnuts to their diet for example. We need our omega-3s and it’s very important that we get some, but be careful of all the hype…
What about Eskimos? Don’t they have lower rates of heart disease because of all the omega-3 they get from a large consumption of fish? Nope, Greenland Eskimos and the Canadian and Alaskan Inuit have heart disease just as often as the non-Eskimo populations.
What about fish oil supplements? High quality scientific studies have found that even long term, high dose consumption of fish oil supplements did not reduce the risk of heart disease, and recent studies show they may do some harm by increasing the risk of atrial fibrillation which increases the risk of getting a stroke.
So yes, we need both omega-3s and omega-6s, but there is no defined RDA (Recommended Daily Allowance) for Omega 3 or Omega 6 oils. However, on average, most adults who consume 17g of omega-6s and 1.6g of omega-3s per day, with nonpregnant women consuming a little less, show no signs of deficiency. Remember that all oils and fats contains 9 Calories per gram so don’t overdo it.
See our professional level information on essential fatty acids, including adequate intake and food source tables.