In recent years, as more people - physicians and patients alike - have come to realize the role that chronic inflammation plays in heart disease, as well as many other diseases, including cancer, there has been a corresponding increase in the use of foods and supplements that contain omega-3 essential fatty acids (EFAs). This is because omega-3 EFAs have proven anti-inflammatory properties that can both prevent and reverse chronic inflammation in the body.
One of the richest sources of omega-3 EFAs is flaxseed oil. Indeed, until recently, it was considered one of the best omega-3 sources, and many Health Experts and other health practitioners routinely recommended it for their patients. However, more recent research shows that regular consumption of flaxseed oil may be dangerous, especially to your eyes.
The reason for this danger has to do with the type of omega-3 EFA that flaxseed contains - alpha linolenic acid, or ALA. ALA comprised 85 percent of flaxseed oil, and is also abundant in canola and soybean oil. All three of these oils are popular health choices for cooking and salads. However, new research published in the Journal of The American College of Nutrition indicates that ALA can be a risk factor for eye diseases such as cataracts because of how ALA causes changes in density in the lens of the eyes.
According to the research, the problem with flaxseed and other ALA-rich oils occurs once they are consumed. During the digestion process, very little of the ALA is able to be converted into EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), the EFAs that have shown to be most effective as anti-inflammatory agents. This is particularly the case with ALA from flaxseed oil because it is so unstable. Additionally, because ALA in flaxseed oil in composed of unsaturated bonds, it is extremely susceptible to oxidation. Oxidation is a primary effect of free radical damage, as well as a major cause of cataracts.
In contrast to flaxseed oil, the researchers found that these health risks to the lens density of the eyes do not exist with animal and monounsaturated fat consumption. (An excellent health choice for monounsaturated fat that is also good for your heart is cold-pressed virgin olive oil.) In a five-year study of 440 women, only ALA was found to be a risk factor for increased lens density. No such risk was found among women who regularly consumed animal and monounsaturated fats.
For this reason, we recommend that you minimize your intake of flaxseed oil. And, in order to protect your heart and arteries from the ravages of chronic inflammation, we also recommend that you choose omega-3s derived from fish. In addition to including fish in your weekly diet, you can also use a high-grade omega-3 fish oil supplement. Unlike omega-3 from flaxseed oil, fish oils contain a rich supply of both DHA and EPA, both of which have strong anti-inflammatory properties. Not only will taking fish oils protect your heart, it may also safeguard your eyesight!
Dietary linolenic acid intake is positively associated with five-year change in eye lens nuclear density. Lu M, Taylor A. Chylack LT, Rogers G, et al. J Am Coll Nutr 2007 Apr;26(2):133-40