A nationwide U.S. study has found that organic milk contains significantly healthier fat composition than conventional milk. This means that organic milk is more beneficial, not only to our diet, but to the cows that give milk.
18-month study from 7 regions
Researchers from Washington State University conducted an 18-month study of 14 different milk processors from seven regions of the U.S. They were located in the Northwest, California, Rocky Mountains, Midwest, Texas, Mid-Atlantic and Northeast regions.
The researchers collected samples from each processor every month for 18 months. The number of samples totaled 220 for the organic milks and 164 for the conventional milks.
The milks were then analyzed in a lab and the results were calculated and analyzed.
The research found that the organic milks contained, on average, 62% higher levels of omega-3 fatty acids than conventional milks. The organic milks also had 25% less omega-6 fatty acids than conventional milks.
In terms of a breakdown of fatty acids, 60 percent higher levels of alpha-linolenic acid (ALA), 32 percent higher levels of eicosapentaenoic acid (EPA) and 19 percent higher levels of docosapentaenoic acid (DPA). Organic milks also had 18% higher levels of conjugated linoleic acid (CLA).
Better fats means greater health benefits
Each of these fatty acids is critical for health. Both alpha-linolenic acid (ALA) and eicosapentaenoic acid (EPA) have been linked with lower risk of cardiovascular disease and along with some cognitive benefits.
Conjugated linoleic acid (CLA) has been linked with better weight control and possibly better insulin reception.
While the omega-3 docosapentaenoic acid (DPA) is not discussed much in medical literature, studies have found that omega-3 DPA will convert to EPA and also to DHA within the liver. (There is also an omega-6 DPA but this does not convert to EPA/DHA.)
A 2012 Harvard study of 1,572 male physicians found that those with higher circulating levels of DPA had significantly reduced (by 45%) risk of heart failure, while higher levels of DHA and EPA had no effect. This study also found that higher ALA levels was also linked to lower risk of heart failure.
Why is organic milk so much more healthier?
The Washington State University researchers observed that one of the reasons for the increased level of fatty acids in milks has to do with the fact that organic cows must be given more pasture time, so they eat more grass and legumes than conventional cows.
Conventional cows are typically fed more grains, primarily corn (and often GMO corn).
The U.S. National Organic Program requires that organic farmers feed their cows at least 30% from pasture grasses.
How does milk compare to fish when it comes to healthy fats?
The researchers also conducted a comparative analysis of organic milks versus seafood using USDA data. They found that on a per-serving basis and compared to the average levels among fish (including Tuna, Halibut, Salmon and Trout), a serving (one cup) of organic milk supplies:
- 273 milligrams of ALA compared to 20 milligrams average in fish
- 35 milligrams of EPA compared to 90 milligrams average in fish
- 46 milligrams of DPA compared to 37 milligrams average in fish
- 0 milligrams of DHA compared to 155 milligrams average in fish
Other nutrients in milk
These increased nutritional features of organic milk are besides the added risk of additional pollutants and hormones found within conventional milk products, given that conventional cows are fed pesticide-sprayed feeds, and given more antibiotics and growth hormones.
With regard to organic milk compared to fish (above): While fish supply significantly more DHA and EPA, organic milk is a better source of ALA and DPA—both of which will convert to DHA and EPA. From the research mentioned above, DPA appears to have better cardiovascular effects than DHA and EPA.
In fairness, there is still considerable evidence from an array of research regarding the health benefits of fish – though mercury and dioxin contamination of fish are considerations.
With regard to the lower levels of omega-6 in organic milks, this is actually a good thing. Increased levels of omega-3 and reductions in omega-6 in our diets have been linked with lower inflammation levels.
With regard to pasteurized, homogenized milk – yogurt and kefir using organic milk – as well as raw milk – are sources for much needed probiotic populations. These uses of milk have been shown in probiotic research to convey other health benefits.
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Case Adams is a California Naturopath and a Board Certified Alternative Medicine Practitioner with a PhD in Natural Health Sciences, and diplomas in Homeopathy, Aromatherapy, Bach Flower Remedies, Blood Chemistry, Clinical Nutritional Counseling and Colon Hydrotherapy. He has authored 26 books on natural healing strategies.