Over the last 100 years, changes in the Western diet have altered the consumption of omega 6 fatty acids (found in meat and vegetable oils) compared with omega 3 fatty acids (found in flax and fish oil) from a 2:1 omega 6/omega 3 ratio (what humans have consumed for most of their history) to a ratio as high as 10:1 omega 6/omega 3. Since omega 6 fatty acids can be converted into inflammatory molecules, this dietary change is believed to disrupt the proper balance of pro- and anti-inflammatory agents, resulting in increased systemic inflammation and a higher incidence of problems including asthma, allergies, diabetes, and arthritis.

Floyd Chilton, director of Wake Forest and Brigham and Women's Center for Botanical Lipids in Winston-Salem, NC and his colleagues, wanting to discover whether these fatty acids also have other effects, fed 27 healthy humans a controlled diet mimicking the omega 6/omega 3 ratios of early humans over five weeks. When they looked at the gene levels of immune signals and cytokines (protein immune messengers) that affect autoimmunity and allergy in blood cells they found that many key signalling genes that cause inflammation were markedly reduced when compared to their number in humans fed a normal 21st century diet. Included in this reduction was a signalling gene for a protein called PI3K, a critical early step in autoimmune and allergic inflammation responses.

For the abstract of the article

First published in September 2009

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