The study is considered a first of its kind, thanks to the large scope of samples tested: Scientists looked at the nutritional makeup of nearly 400 organic and nonorganic milk samples collected over an 18-month period from across the United States.
They found organic milk was full of beneficial omega-3 fatty acids that help promote healthy hearts—much more so than the nonorganic milk.
But that's not the entire story. Not only did the nonorganic milk contain lower levels of the good fat, but it also harbored higher levels of inflammation- and disease-promoting omega-6 fats; the healthy omega-6 to omega-3 ratio was not as favorable as in the organic milk. While we do need some omega-6s in our diets, Americans tend to drastically overeat this type of fat. (It's the fat found in many junk foods and fried foods.)
"Nature designed us to have a certain balance between omega-6 fatty acids and omega-3 fatty acids, but we've upset this balance in the last 100 years," explains study coauthor Donald R. Davis, PhD, a Washington State University research associate.
Organic milk can also fight depression! Find out how in The Happiness Diet!
Eating too many omega-6s and not balancing them with omega-3s creates the unhealthy consequence that they then interfere with proper blood clotting, deregulate blood pressure, affect mood, disrupt reproductive functions, and cause widespread inflammation. The imbalance also interferes with the body's already limited ability to convert alpha-linolenic acid (ALA) to the more potent DHA and EPA polyunsaturated fatty acids that our brains need. Too many omega-6s can even interfere with our cells' ability to function normally.
The good news for organic milk lovers? Averaged over a 12-month period, organic milk contained 62 percent more beneficial omega-3 fatty acids
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The difference in quality isn't rocket science, either. Cows that eat a poorer diet produce milk with less-favorable fat profiles than those eating a more natural grass-and-legume-based diet. In organic systems, cows are required to eat 30 percent of their diet from pasture grasses and legumes at least 120 days of the year. There's no rule like that in conventional dairy farming, which often has cows living on mixed grains. "Over the last 20 years or so, conventional dairies have increasingly cut down on the amount of pasture feeding that dairy cows get, and have increased the amount of diet that comes from high-energy concentrates which consist of corn and soybeans," Davis explains. "These are very unnatural sources of food for cows.
One caveat? If you want to enjoy the health benefits of milk that can help get your omega-6 to omega-3 ratios in order, you'll need to choose whole milk, and preferably, organic whole milk. "If you get organic skim milk, you might not be getting the advantages we're talking about in terms of fatty acids," Davis notes.
Don't be freaked out by the fat, either. "Fortunately, some experts in the field in the last 10 years have begun to strongly question the advice we've all heard for the last 30 years, the notion that we should all be consuming reduced-fat or no-fat milk," Davis says. Those recommendations were based on theories and never panned out in well-designed experiments.
There are other benefits to choosing organic milk. The cows are not injected with genetically engineered growth hormones, and their feed isn't laced with antibiotics, GMOs, or chemical pesticides.
The study will appear in the peer-reviewed journal PLoS One.
Find a better brand. For the highest beneficial fat levels, look for organic dairies that really push for pasture and go beyond the minimum requirements. To find an organic dairy brand that lives up to your standards, search the Cornucopia Institute's organic dairy scorecard. The organization promotes family-scale sustainable farms and continually updates it's scorecard, ranking organic brands on the market.
Beware of milk replacers. Don't like milk? Be careful with milk replacement products, too. Some soy and coconut milk products contain carrageenan, a thickening agent that is linked to digestive tract damage in some studies.
Expand your organic arsenal. Organic dairy is known as the "gateway" food that helps usher people into the world of organic foods. For more reasons to clean up your diet, read 7 Things You Need to Start Buying Organic.