Omega-3 Fatty Acids Balance the Immune Response

A recent study investigated how immune system responses in mice change when different types of oils are present in the diet. This study revealed that omega-3 fatty acids promote an immune response known as a T helper-1 response, or Th1 response. T helper cells are a type of white blood cell known as lymphocytes. Lymphocytes are important because they play a role in directing and activating other white blood cells. Th1 cells release specific cellular signaling molecules known as cytokines. Th2 cells release cytokines that promote antibody production and are often over-active in hypersensitivity immune responses.

At 4 weeks of age, mice were given either an influenza vaccine to evaluate delayed-type of hypersensitivity reactions or were sensitized to ovalbumin, an allergenic protein found in eggs. At 6 weeks of age, mice were fed a diet supplemented with one of several oils for 7 weeks, including sunflower oil, which is rich in linoleic acid; linseed oil, which is rich in alpha-linolenic acid; salmon oil, which is high in marine omega-3 polyunsaturated fatty acids; or beef tallow, rich in saturated fatty acids.

The study found that the mice receiving the influenza vaccine and the omega-3 polyunsaturated fatty acids had the greatest delayed-type hypersensitivity reaction compared to the mice supplemented the other oils. This indicates that omega-3 fatty acids promote the Th1 response. In the mice sensitized to ovalbumin, the mice supplemented with the omega-3 fatty acids showed less of a sensitizing skin response compared to the mice fed the other oils. This finding suggests that omega-3 fatty acids also lessen the Th2 response. Furthermore, the mice fed the diet high in saturated fatty acids had the most sensitizing skin response compared to the other groups, suggesting that high saturated fat intake may be related to increased sensitivity of immune responses.

The researchers stated, “In conclusion, using 2 different models of immune responses demonstrates potential benefits from marine omega-3 polyunsaturated fatty acids.”

Reference:

Hogenkamp A, van Vlies N, Fear AL, van Esch BC, Hofman GA, Garssen J, Calder PC. Dietary Fatty Acids Affect the Immune System in Male Mice Sensitized to Ovalbumin or Vaccinated with Influenza. J Nutr. 2011 Feb 23. Published Online Ahead of Print.