Dietary Supplement Supports Healthy Lipids

A new study investigated the effect of a dietary supplement on oxidized low-density lipoprotein (LDL) cholesterol. LDL cholesterol (“bad” cholesterol) can become oxidized by reacting with damaging free radicals. This, in turn, makes the LDL more reactive, which leads to damage of the inner lining of the blood vessels. Oxidized LDL promotes the accumulation of inflammatory cells, called foam cells, and platelets, which leads to the deposition of cholesterol and other fats on the inner walls of arteries. This results in the formation of plaques and the development of atherosclerosis. Some research suggests that oxidized LDL is a better predictor of future heart attacks than unoxidized LDL.

In this new study, researchers supplemented healthy men between 53 and 65 years of age with the omega-3 fatty acid docosahexaenoic acid (DHA) at increasing doses of 200, 400, 800 and 1,600 mg/day; the men took each of these doses for two weeks in succession. At the end of each two-week period, the subjects’ blood was evaluated for markers of oxidative stress, oxidized LDL and antioxidant levels.

The results showed that as the dose of DHA increased, the amount of DHA incorporated into the LDL cholesterol also increased. The 200, 400 and 800 mg per day dosages were found to increase levels of alpha-tocopherol (vitamin E), and decreased levels of malondialdehyde (MDA), which is marker of oxidation. These dosages also resulted in an increased lag-time to induce oxidation of the LDL in vitro, meaning the LDL with the incorporated DHA was more resistant to oxidation. The study also showed that levels of the oxidation byproduct of omega-3 fatty acids, 4-hydroxy-hexenal, increased after the 800 and 1,600 mg per day dosages, while there was no change in the levels 4-hydroxy-nonenal derived from the oxidation of the omega-6 fatty acids.

The study authors concluded, “Our results clearly show that an intake of 200–800 mg/day DHA may have protective and antioxidant effects on LDL and could represent optimal doses for cardiovascular disease prevention in a healthy population.”

Reference:

Calzada C, Colas R, Guillot N, Guichardant M, Laville M, Véricel E, Lagarde M. Subgram daily supplementation with docosahexaenoic acid protects low-density lipoproteins from oxidation in healthy men. Atherosclerosis. 2010 Feb; 208(2): 467-72.