Knowing what to eat so that we get enough omega-3 fats in our diet is easy. The challenge is how to cut back on omega-6.
The first step to get our levels of omega-3 and omega-6 fats in balance is to reduce how much omega-6 we eat. Most people focus instead on increasing omega-3s.
As a starter this won't work well, however, because the ratio between these two polyunsaturated fats that most Americans have is so out of balance. Many of us have 20 times the amount of omega-6 in our systems as omega-3, while population studies indicate that ratios of twice as much omega-6 to omega-3 is ideal for our heart health. While everyone needs to protect his or her heart, people with diabetes have a special interest in our most common and most serious potential complication.
The problem is that these two fats compete to get into the cells of our bodies. When we overload on the pro-inflammatory omega 6s, the anti-inflammatory omega-3s can't do the work that they need to do to fight the inflammation that more and more people are recognizing as a root cause of many chronic diseases, including diabetes.
The leading expert on omega-3 and omega-6 is Dr. Bill Lands, who until he retired in 2002 was a senior scientific advisor at the U.S. National Institutes of Health. Dr. Lands "is credited for discovering the beneficial effects of balancing the effects of excess omega-6 fatty acids with dietary omega-3 fatty acids," according to the Wikipedia article about him.
While Dr. Lands has written books and numerous scientific papers on these fats, many of which I have studied, his most recent and most persuasive report is a videotaped presentation that he made in October 2009 to a group of military doctors at the National Institutes of Health. This talk at the "Workshop on Nutritional Armor for the Warfighter," is available online and is well worth 37 minutes of everybody's time. The address is http://videocast.nih.gov/summary.asp?live=8108. You can skip the first 12 minutes of introduction to get to his presentation by moving the cursor slightly to the right after the streaming begins.
One of the key slides shows that in population studies as the ratio of omega-6 to omega-3 goes up, the heart attack death rate climbs proportionally:
Heart Attack Deaths Go Up with Unbalanced Omegas
Another slide took me a while to understand. But this is the key one showing why we have to cut back on omega-6 fats before we can get much benefit from the omega-3 fats that we eat:
Added Omega-6 Decreases Effect of Omega-3
Even after watching Dr. Lands's presentation several times and puzzling over this slide, I wasn't sure that I understood its significance. So I finally wrote Dr. Lands: "In your recent NIH talk to U.S. Army doctors, you state (at around 29 minutes) that a lot of articles in the literature say that the short-chain omega-3 is not very effective. But, you add, that was because they were all done in the presence of substantial excesses of omega-6.
"Does that mean that when we have a more balanced omega-3/omega-6 ratio, a much higher proportion of ALA [alpha linolenic acid, the short-chain fatty acid that is our only vegetarian source of omega-3] is converted into the long-chain n-3 fatty acids than the 4 to 8 percent that studies like the 2007 Circulation report, which you co-authored, state? Because of this apparently low conversion, I have been largely discounting the importance of ALA even in a balanced diet like mine. So if I understand you correctly, this is very important."