The finding, published Monday in the journal PLOS One, found that organic milk has a more favorable balance of omega-3 (found in fish and flaxseed) and omega-6 (found in vegetable oils and fried foods) fatty acids.
Drinking whole organic milk "will certainly lessen the risk factor for cardiovascular disease," said the study's lead author, Charles M. Benbrook, a research professor at Washington State University's Center for Sustaining Agriculture and Natural Resources.
The reason for that is because organic milk comes from dairy cows who spend time in the pasture, eating grassy plants that are high in omega-3s. Conventional milk comes from cows who eat an unnatural corn-based diet, which is high in omega-6s. And low- and nonfat milk has been stripped of its essential fatty acids along with its fat.
The researchers examined 384 samples of organic and conventional whole milk over 18 months taken from around the United States. They found that organic milk contained 62 percent more omega-3 fatty acids and 25 percent fewer omega-6s than non-organic milk. The ratio of omega-6 to omega-3 in the organic milk was 2.28. That ratio was a much higher 5.77 in conventional milk. The lower the ratio, the better for your health, according to the scientists.
"As we in the U.S. have progressively moved away from pasture towards feeding corn and soybeans, which aren't the natural diet for cows, the omega-6 to omega-3 ratio goes up," study co-author Donald Davis said.
According to Davis, Americans typically have too much omega-6 in their diets, which some experts believe is linked to an increased risk of cardiovascular disease, cancer, excessive inflammation and autoimmune diseases. Most Americans eat more than 10 times as much omega-6 as omega-3. While the ideal ratio of omega-6 to omega-3 in the body is thought to be 2.3-to-1, the ratio in most Western diets is between 10-to-1 and 15-to-1, according to the study.
Davis also said the longstanding assumption that the saturated fats in whole milk raise the risk of cardiovascular disease may be simply wrong. In fact, Davis said, "A systematic review of lipid-lowering agents concluded that omega-3 fatty acids are as effective as statin drugs in lowering cardiovascular disease risk."
Although the Dietary Guidelines for Americans issued by the U.S. Department of Agriculture and the Department of Health and Human Services recommend consuming reduced-fat milk, the health benefits of milk decrease for people consuming lower-fat or skim varieties, he said.
"The evidence [that low-fat is better] is pretty weak, and there's quite a bit of evidence that full-fat milk has beneficial properties," Davis said. He argues instead that the ingredients in whole milk (which include omega-3 fatty acids, conjugated linoleic acid, the possibly beneficial trans fatty acids trans-18:1 and trans-16:1, calcium, potassium, vitamin D (in fortified milk), vitamin B12, protein and protective minerals) actually improve health: "Additional studies have linked dairy fat consumption to diminished weight gain, attenuated markers of metabolic syndrome, including waist circumference, and reduced risk of cardiovascular disease and colorectal cancer."
"Though the dietary guidelines for the U.S. for many years have recommended reduced fat, I think that will probably change some day," he said.
Davis and his colleagues analyzed how a typical American woman could best alter her ratio of fatty acids. They said the most effective method would be to cut down on omega-6 fatty acids and switch to whole organic milk, while also increasing the total amount of milk consumed -- to four and a half glasses a day. (That is a lot of PB&Js.)
"If you did all these things, you'd get 80 percent of the way to what some people think is a more ideal ratio of about 2.3 instead of typical Americans ratio of being up high around 10 or 15," he said.
The scientists conclude that "Improvements in the nutritional quality of milk and dairy products should improve long-term health status and outcomes, especially for pregnant women, infants, children and those with elevated cardiovascular disease risk. The expected benefits are greatest for those who simultaneously avoid foods with relatively high levels of omega-6s, increase intakes of fat-containing dairy products, and switch to predominantly organic dairy products."
No word on how whipped cream factors into all of this.
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