You may have noticed a growing trend of grass-fed organic milk available at your local supermarket. This is a shift partly due to farmers as well as to consumers, and in both cases have to do with the environmental, public health and animal welfare benefits associated with grass-fed systems. Researchers have now learned that cows that are fed a diet that is nearly 100 percent organic grass- and legume-based produce milk that have increased levels of omega-3 and conjugated linoleic acid (CLA). Americans tend to consume diets which contain increased levels of omega-6 for every gram of omega-3, an imbalance which has been shown to elevate the risks of cardiovascular disease, diabetes and obesity. The study shows that grass-fed organic milk and dairy offer an improved balance of fatty acids at a ratio close to 1 to 1 for omega-6 and omega-3, as opposed to conventional whole milk, which is 5.7 to 1.
The study, "Enhancing the Fatty Acid Profile of Milk Through Forage-Based Rations, with Nutrition Modeling of Dietary Outcomes," is published in Food Science and Nutrition, and is a collaborative project conducted by the University of Minnesota, Johns Hopkins University, Newcastle University, Southern Cross University, NSW Australia and the Aarhus University Hospital.
If you drink milk, the results of this study show that grass-fed organic milk will give you the greatest bang for your buck when it comes to omega balance. Though the benefits of grass-fed dairy supersede those of both simply organic and conventional, the benefits of milk consumption are often overstated. However, as we've learned through other studies, well-managed pasture-raised animals can provide multiple environmental benefits, including improved soil health, which can enhance water retention, reduce runoff and even offset some greenhouse gas emissions.
To reach the conclusions about grass-fed dairy, the team conducted an analysis of over 1,160 samples of whole grass-fed milk, prior to any processing, over the course of three years. While the study does not address the question of how processing and packaging for retail might affect fatty acid levels, it nonetheless highlights the concept that feeding our livestock better leads to better products.
The samples for the study were obtained by farmer members of CROPP Cooperative, best known for their brand Organic Valley, who also contributed funding to the research. CROPP acknowledges on the website Hygeia Analytics that their role in the study might lead some to suspect bias. "There is a presumption today that 'industry' funded research is usually tainted by clever to overt bias," they say. "The journal Food Science and Nutrition has extensive and rigorous policies calling for full disclosure of potential competing interests, as well as disclosure of funding sources. We complied with each."
There is some promising evidence that grass-fed organic milk is more nutritious than its conventional and not grass-fed counterparts, this study being the latest indication. In addition to the possible nutritional benefits, however, we can safely say that the benefits to pasture-based systems reach beyond good nutrition; in addition to the environmental benefits of pasture-raised dairy, animals raised on pasture are better adapted to their natural environments and have less negative health outcomes.