Organic milk contains significantly higher concentrations of heart-healthy fatty acids compared to milk from cows on conventionally managed dairy farms, according to a new study published in the journal PLOS ONE.
Washington State University researchers tested nearly 400 samples of U.S. organic and conventional milk over an 18-month period.
Conventional milk had an average omega-6 to omega-3 fatty acid ratio of 5.8, more than twice that of organic milk’s ratio of 2.3. The researchers say the healthier ratio of fatty acids in organic milk is brought about by a greater reliance on pasture and forage-based feeds on organic dairy farms. Research has shown that grass and legume forages promote cow health and improve the fatty acid profile in organic dairy products.
The team also compared the fatty acids in dairy products to those in fish. Conventional milk had about nine times more ALA than fish while organic milk had 14 times more. Organic milk is also a significant source of two other omega-3 fatty acids, EPA and DPA, but not DHA.
“We were surprised to find that recommended intakes of full-fat milk products supply far more of the major omega-3 fatty acid, ALA, than recommended servings of fish," said co-author and WSU research associate Donald R. Davis.
After fruits and vegetables, dairy products are the largest category of the growing $29 billion organic food sector, according to the Organic Trade Association’s 2013 Organic Industry Survey. Organic milk and cream sales were worth $2.6 billion, the survey found.
The consumption of more omega-6 fatty acids than omega-3 fatty acids is a well-known risk factor for a variety of health problems, including cardiovascular disease, cancer, excessive inflammation and autoimmune diseases. The higher the ratio of omega-6 to omega-3, the greater the associated health risk.
