Despite their economically impoverished living conditions, Amerindian mothers produce breast milk that is significantly higher in omega-3 fatty acids than their American counterparts, says a new study by anthropologists at the University of California Santa Barbara (UCSB).
The study, which was published in the May 2012 issue of Maternal & Child Nutrition, compared the composition of fatty acids in milk samples from indigenous Tsimane women residing in lowland Bolivia with milk samples from American women in Midwestern urban populations.
Fatty acids, in particular the omega-3 fatty acid docosahexaenoic acid or DHA, are important for the proper growth and development of babies. DHA is especially important for proper brain and eye development. Omega-6 fatty acids, another type of fatty acids, has been linked to increased risks of obesity, inflammation, and cardiovascular disease. The ratio between omega-3s and omega-6s is most important; early humans likely had ratios that were equal.
Breast milk is the only source of fatty acids for infants who are exclusively breastfed. However, the fatty acid composition of breast milk varies considerably from woman to woman depending on her diet. Mothers who eat diets high in omega-3-rich foods produce breast milk that is higher in fatty acids.
Upon comparing the milk samples from the Amerindian and the American mothers, the researchers discovered that the Amerindian mothers produced milk with omega-6 to omega-3 ratios that were four to one. In the United States, however, the women were producing milk with rations varying between as low as ten to one and as high as twenty to one. Furthermore, the average percentages of linoleic and trans fatty acids were 84 percent and 260 percent lower in Amerindian mothers compared to American mothers.
In other words, the breast milk produced by the mothers in the more impoverished area is significantly more balanced than the milk produced by mothers in the more affluent United States. The reason is likely because, although poorer, Amerindian women tend to eat diets of locally grown staple crops, wild game, and freshwater fish compared to the highly-processed, nutritionally-poor diets of American women.
As Melanie Martin, a doctoral student in UCSB’s Department of Anthropology and the study’s lead researcher, says on Medical News Today:
“The study suggests that standards of fatty acid composition for infant formulas should be derived from populations such as the Tsimane. And nutritional recommendations for infants should account for the prolonged requirements of fatty acids that breast milk naturally provides.”
American mothers can improve their breast milk by eating fewer processed foods and more foods naturally high in omega-3 fatty acids such as cold water fish and certain plant oils.
How do you ensure that you get enough healthy omega-3s in your diet?