A recent WSU study claiming that organic milk is more nutritious than regular milk is finding its contents to be the de novo dogma for consumers who afford the purchase of organic foods a reverence to be envied by most religions.

It’s unfortunate, however, that the study seems to be missing the hallmarks of a phenomenon called “good science.” Before these assumptions about organic milk are incorrectly entered into the realm of scientific fact, a back-to-basics discussion of the scientific method and dairy science is needed.

According to the study published by PLOS ONE, organic milk contains a higher amount of omega-3 fatty acids, thus obtaining a lower omega-6 to omega-3 fatty acid ratio. Omega-3s are associated with health benefits, leading nutritionists to recommend consumption of food products with a low omega-6: omega-3 ratio.

Led by WSU research professor Charles Benbrook, researchers looked at 384 milk samples from United States milk processors, according to both The New York Times and the study itself. These samples were collected from 14 milk processors over an 18-month period.

The study compared organic and conventional milk but failed to establish scientific controls, a vital component to the scientific method. When doing an experiment, scientists establish multiple testing groups, one of which is a control group.

The control group allows scientists to make accurate conclusions since the only variable that differs between the testing groups is the one being examined by the researcher conducting the experiment.   

For example, if comparing milk from organic dairy cows to their conventional counterparts, the composition of the diet and the living conditions would not differ between the groups. Organic cows would be fed a diet containing organic ingredients while regular cows would receive a comparable diet of conventional feedstuffs.

If this study had been concerned with the scientific method, a similar model to the aforementioned system would have been used. Instead, milk was collected from the milk tanks based on whether it was labeled “organic” or “conventional”, according to the study’s methodology section.

As all scientists know, labeling is a foolproof way to avoid contamination or experimental mistakes because no one has ever mislabeled anything.

However, far more serious is the study’s deliberate neglect of the dietary differences between conventionally-fed and organically-fed cows. Many conventionally-fed cows are provided with a diet known as a total mixed ration, which typically contains a higher percentage of grain products. Organic cows obtain more of their nutrients from pasture.

For the most part, the cattle examined in this experiment reflect the prominent diet and management system favored by each agricultural system.

It is well known by the scientific community that pasture-fed cows produce milk with a higher level of omega-3s whereas ration-fed cows produce milk that contains less of omega-3 fatty acids, according to numerous articles published by the Journal of Dairy Science.

The results of Benbrook’s study mirror that which scientists already know, yet the article seems determined to recommend a shift from conventional to organic dairy systems rather than a shift from ration-fed to pasture-fed dairy cows.

Even though the study acknowledges that there are differences in milk fatty-acid composition due to dietary influences, the authors have decided to break down the dairy universe into two components: organic and conventional. For the purpose of this investigation, WSU researchers have decided that organic means pasture-fed and conventional means grain-fed.

As mandated by the U.S National Organic Program, organic dairy cows must receive 30 percent of their diet from pasture. This means that the other 70 percent can be in the form of a total mixed ration or grain-based diet. Thus, organic production does not mean the same thing as pasture-fed.

There are organic, grain-fed diets and conventional, pasture-fed diets. Dairy production is not black and white. It’s gray, and dairies come in all shapes, sizes and management systems.

The results found by the study actually contradict the authors’ final conclusions. According to the study, organic and conventional milk taken from California dairies were similar in fatty acid composition because most dairies in northern California rely on pasture, meaning that both types of cows are grazed on pasture for over 250 days per year.

The study referred to these results as unexpected and failed to discuss it further. One can only assume that the researchers deliberately failed to recognize this as a key piece of evidence that the type of diet trumps the organic label in regard to milk’s nutritional qualities.

Key principles of the scientific method and of dairy science are missing from Benbrook’s study, making the article a display of the political agenda behind the study rather than revealing any scientific breakthrough.

Additionally, if organic dairy cows do turn out to have superpowers, you will probably find out about it from the Journal of Dairy Science, not PLOS ONE.  

-Corrine Harris is a senior animal science major from Edmonds. She can be contacted at 335-2290 or by [email protected]. The opinions expressed in this column are not necessarily those of the staff of The Daily Evergreen or those of Student Publications.