That You Can't Get From Flax By Geoffrey R. Harris, MD
We all know omega-3 fatty acids are important. Many people think of flax and flax seed oil when they want to get the right amount of omega-3 in their diet. Unfortunately, research is showing that the omega-3s in flax may not be enough. Read on to find out more.
The common omega-3 in plants and flax is called alpha-linoleic acid (ALA). ALA is considered an essential fatty acid because our bodies cannot make omega-3 or omega-6 fatty acids. This means we must get our omega-3 fatty acids from our diet. Omega-3 fatty acids, once lengthened, are used in many ways in our bodies: in cell membranes to allow for flexibility and signaling across the cell surface, in the eyes to preserve and protect vision, in the brain to improve nerve cell function and maintain memory and cognition, and as precursors for immune system hormones that control inflammation. Getting omega-3 fatty acids, and especially long-chain (lengthened) omega-3s, is an important part of a healthy diet.
Remember that because of the way the body absorbs and utilizes the essential fatty acids, there is a competition between omega-6 and omega-3. Because of this competition, the nutritional experts at SuperFoodsRx consider a near equal dietary ratio of omega-6 to omega-3 to be a crucial part of a healthy diet. However, due to the pervasive use of vegetable oils like corn and soybean oil, the typical Western diet has a dietary ratio of omega-6 to omega-3 of about 10 to 1. We encourage limiting the amount of vegetable oils in the diet, increasing the amount of omega-3 from plant and marine sources, and cooking with monounsaturated oil like olive oil which doesn’t add too much omega-6.
But why isn't flax sufficient? As mentioned above, ALA is the common omega-3 in plants (and flaxseed). This fatty acid is considered a short-chain omega-3 because it must be lengthened for use in the body. The omega-3s that can be used in the body are the long-chain omega-3s DHA (docosahexaenoic acid) and EPA (eicosapentenoic acid). Fish and fish oil are a source of DHA and EPA that are ready to be used by the body—they do not need to be lengthened or altered before they are utilized by the cells, brain, and eyes. However, ALA from flax and plant sources must be elongated by our bodies to EPA or DHA before it can be used.
Research has shown that this elongation process is very inefficient in the human body. Studies have revealed that healthy men can only convert about 8% of dietary ALA to EPA and less than 4% to DHA. Due to the effects of estrogen, young women can convert about 21% of dietary ALA to EPA and 9% to DHA under optimal circumstances, but this process becomes less efficient with age. Furthermore, there is more competition between omega-6 and omega-3 fatty acids during the process of elongation. A high ratio of dietary omega-6 further inhibits the lengthening process by 40 to 50%. Many experts feel that conversion of dietary ALA in the human body to the important, long-chain omega-3s is not sufficient to ensure the necessary amount of DHA and EPA for optimum health.
So what this means is that while flax is an excellent source of short-chain omega-3s to help tip the balance away from an omega-6 rich diet, we really need to get long-chain omega-3s from our diet or from supplements. Eating fish is an excellent way to get these long-chain omega-3s, as is taking a fish oil supplement. Vegetarians who do not eat fish or use animal products may have had difficulty getting the long-chain omega-3s, but now there is another way to get DHA and EPA.
Marine algae, tiny aquatic plants, make DHA and EPA naturally. In fact, fish get their DHA and EPA by eating the algae or by eating other fish that have eaten the algae. Marine algae are a great source of DHA and EPA and are now being used to make animal-free, long-chain omega-3 supplements. I recommend taking an omega-3 supplement with 500 to 1000 mg of DHA and EPA made from fish oil or marine algae daily.
Finally, the smart consumer knows to always read your food labels. Products that indicate they contain omega-3s typically indicate whether they contain long-chain omega-3s. If you don’t see any indication of DHA or EPA on the label, it probably doesn’t contain any of the important long-chain omega-3s. |