Is there a special role for Omega-3 Fats from Walnuts and Flax Seed – ALA?
Competency # 13 Fats
Reference: Am J Clin Nutr 2007;85:385-91 Zhao and Etherton at Penn State
Yes. Ok, you can stop here. Or, you can understand an interesting study just published in the American Journal of Clinical Nutrition this February by Zhao from Penn State in the Feb edition on dietary effects of ALA (alpha linoleic acid) on your body’s inflammation.
We know that the Mediterranean diet is good for us in that it correlates with a dramatic reduction in heart disease risk. There are about 50 foods that are eaten regularly in the Mediterranean diet, but olive oil and lots of vegetables and fish are key to much of the diet. That diet also has an abundance of omega fatty acids in it. Fish and fish oil are now well established sources of omega-3 fatty acids that I have encouraged you to eat. What about ALA, an omega fatty acid common in vegetable sources? Does it help or hurt? Key to us in North America is the environment we live in that has an abundance of omega-6 fatty acids that seem to be correlated with inflammation. Can we find a dietary strategy that avoids that inflammation? We think so. This study says yes.
What this study did was to examine the inflammatory markers in our white blood cells called tumor necrosis factor and another called IL-6. These markers drop to the degree that ALA activates something called the PPAR, or the peroxisome-proliferator activated receptor. You will hear more about the PPAR system sometime this year because it seems to be a key player. Activating that system turns on the genes in your white blood cells. Not only does ALA change those inflammatory markers, it changes the ability of our white cells to stick to the walls of our arteries. It’s that sticking stuff that gets our arteries damaged when white cells attack the artery, and then the LDLs bring in the garbage fats. That happens every day, after every meal, year after year.
But to get a sense of what this dietary change did, here are some numbers. In an Average American Diet, your IL-6 is 239 ng/L. The ALA diet in this study lowered that to 107. Their TNF went from 18.2, to 10.3. The study subjects were all a bit pudgy, a bit high on their cholesterol and middle-aged without any active disease, just middle-aged folks.
What did they eat to do that? About 1.3 oz a day of walnuts and .8 oz of flax seed. Add a little walnut oil in one of their other groups. These are not big changes. But what happened in their blood was big. This study is a physiology study. It shows how something works. To prove it reduces artery disease will take a prospective trial that takes years. I’m not willing to wait.
WWW. What Will Work for Me? I think this is pretty impressive. Walnuts are good for us. Flax seed is too. We can now say for certain that adding ALA to our diets makes a difference. It lowers your inflammatory markers. Fish oil is on the official list. I’m predicting, based on this and other similar studies, that the formal recommendation will be for you consistently find ways to add walnuts and flax seed to your diet. It’s just a matter of time. Let’s just beat them to it and start sooner.