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Is the title misleading?

Posted by THEGAP on 10 Dec 2013 at 17:58 GMT

This work is very interesting for all those who advocate nutritional quality based on detailed information of the consumer.
After the failure of the low fat policy and the continuous growth of obesity prevalence, one should question the present paradigm where fat would be bad, saturated fat would be worse and cholesterol would be a culprit. These assertions are obviously wrong about milk and dairy products because they appeared to be protective for CVD in epidemiological studies. More, several years ago, a Swiss team coined the term Swiss paradox about the low prevalence of CVD in Switzerland and they attributed it to the consumption of alpine cheeses made of grass-fed milk.
In this setting, present dairy products although made of a white milk are very different from those our ancestors drank or ate a few generations ago. Cattle was grass-fed, cow production of milk was not stimulated by hormones, cattle was very active during 3/4 of the year in nature and pasteurized products unknown.
Several differences were recognized between grass-fed milk and grain or legume fed milk in confined feeding operations. These differences are not only quantitative but also in the detailed composition of fatty acids. Obviously due to the involvement of the W6/W3 PUFA ratio in inflammation and other chronic conditions these differences are not meaningless.
Authors of this study bring to the consumer a valuable information about the possibility to improve the W6/W3 PUFA ratio with dairy products. But these organic products, when labelled, are more expensive and one should question the difference between organic and grass-fed and its consequences.
Therefore my question is about the meaning of this study.
Is it eventually a study which shows that grass-fed milk is of higher nutritional value than grain or legume fed cows or a study which shows that organic feeding is of higher nutritional quality?

No competing interests declared.

RE: Is the title misleading?

drdavis2 replied to THEGAP on 10 Dec 2013 at 22:41 GMT

Thank you for your comment, including about the Swiss paradox. You ask whether our study shows benefits from grass feeding vs. organic feeding. We attribute our reported shifts in fatty acids to the substantial grass- and conserved-forage feeding required for organic milk in the U.S. "Organic milk" is the readily identifiable consumer product that we studied. We discuss one small area in northern Calif. where conventional milk with similar levels of grass feeding yielded similar fatty acid benefits. But there are no standards for such milk (as there are for grass feeding for organic milk), and it has no distinctive labeling, so consumers can't know what they are getting. If there is sufficient consumer demand, standards and marketing might be developed for "grass-enhanced" conventional milk. Its fatty acid profile could be documented, and it might be able to compete at a lower price with organic milk, which people often buy for reasons other than its fatty acids.

Competing interests declared: I am a coauthor of the study, which was supported by Organic Valley.

RE: RE: Is the title misleading?

ulfmag replied to drdavis2 on 15 Jan 2014 at 19:53 GMT

Isn’t the title of this study supported by Organic Valley indeed miss-leading or to narrow? The literature cited and the data from the Californian case do – which the authors rightly claim – suggest that it is the access to pasture for the cows that is crucial for the composition of fatty acids in milk. In an international perspective is generous access to pasture not the privilege for “organic cows”, even if this seems to be the case in US. The title is thus relevant for the US consumers market, but misleading for the broader international scientific community.

No competing interests declared.

RE: RE: RE: Is the title misleading?

cbenbrook replied to ulfmag on 17 Jan 2014 at 22:02 GMT

We agree that our title could be improved from an international perspective. However, it should help that the title identifies our study as United States-based. More importantly, the text notes international differences in dairy cow feeding, and we make clear that pasture feeding is primary responsible for our reported shifts in fatty acid profiles. We mention pasture feeding 17 times in 9 separate paragraphs. Our Introduction lists 10 references for pasture-related increases in ω-3 and CLA fatty acids, and it describes the substantial pasture requirements for U.S. organic dairies. The Discussion references the low access to pasture at U.S. conventional dairies in 2007 (only 22% of cows, often for only short duration with very high animal density); the similarity of our conventional and organic samples from Humboldt county, California; and the unique dependence of CLA on pasture feeding. In our concluding paragraph we note that "both conventional and organic dairies can benefit from grazing and forage-based feeds," and we hope our study, and growing public interest in grass-based diary production, will help halt declining pasture feeding by conventional dairies in the U.S. Note that our title would be more fundamentally questionable if we simply replaced "organic production" with "pasture feeding," because we have no basis for concluding that other aspects of organic production have no effect on fatty acid profiles (e.g., avoiding antibiotics, steroids, and growth hormone). We compared only organic and conventional dairies in the U.S. In hindsight, a better title might add four words at the beginning: "Required Pasture Feeding of Organic Production Enhances Milk Nutritional Quality by Shifting Fatty Acid Composition: A United States–Wide, 18-Month Study."

Don Davis and Chuck Benbrook, for the team

No competing interests declared.