Walter Willett, MD, DrPH, provided a shocking end to the webcast Wednesday about the science behind the proposed new U.S. Dietary Guidelines report, calling the origin of a key recommendation “bizarre” and highlighting its negative consequences for health and the environment. His comments are so important and well-phrased that I went back to the webcast to transcribe most of them for you.
Background: Scientists at Harvard, UNC, Tufts, and other locations who contributed to Dietary Guidelines report explained it chapter by chapter for over two hours. Dr. Willett’s role was to provide comments at the end. There’s plenty of reason for the committee to listen. Willet is the chair of the Department of Nutrition at Harvard School of Public Health, professor of medicine at Harvard Medical School and, according to the Menus of Change website, “the most cited nutritionist internationally and is among the five most cited persons in all fields of clinical science.”
Praise for daring recommendation to eat less meat
Willett first praised the committee’s collective effort, including the emphasis on foods instead of single nutrients. He got knowing laughs for praising the risk they took by recommending that Americans eat less red meat and less processed meat. After all, Willett said,
No one since Dr. Hegsted at the very beginning has dared to say that because he lost his job because of saying that at the beginning of the guidelines process. Maybe it’s a good thing that you are volunteers but that evidence is strong. There’s been evidence before but it was really obfuscated under the wording of “solid fats.” When you look on page 60-some of the last report and it notes in a fine-print footnote that solid fats come from dairy fats and meat fats. To be able to say that up front is, I think, important and a clear message that also will engender pushback for that very reason.
Basis for recommending more dairy consumption is “bizarre”
Willett continued:
… there’s one area that does trouble me and that is the recommendation to consume more dairy products, specifically low-fat or fat-free dairy products.
I think this represents essentially something the committee had little control over and is a structural problem with the process. The USDA and HHS needs to get their heads together and solve this structural problem because the report committees in past in, recent years have been told and the report reflected that the guidelines must meet the IOM DRIs [Daily Recommended Intakes].
And that is a problem when you start going back and looking at where those IOM DRIs came from. And for calcium, if you dig back, the basis of those guidelines – the DRIs for adults – for calcium, essentially it says we’re supposed to get a thousand or twelve hundred milligrams of calcium per day. That’s based on studies that lasted only 2 to 3 weeks looking at how much calcium we put in our urine and our feces given a certain amount of calcium consumed.
It’s not supported, and the report does acknowledge, it’s not supported on any evidence of benefits or fractures which is the point that we really care about. The focus is said to be bone health. It’s not that there’s no evidence, there’s lots of evidence including meta-analyses, that milk consumption, dairy consumption, is not related to fracture risk within the range in the US population. A good thing is that the guidelines do not say specifically, ‘Get three servings of dairy per day,’ but if you look at the documents on the modeling, it assumes that intake of calcium. You pretty much need to get to three servings of dairy a day to get that.
It’s bizarre to think that that recommendation is being driven by 2- to 3-week studies and just a couple hundred people. It’s actually refuted by large, long-term epidemiologic studies looking at the fracture risk.
I think we need to essentially liberate the process a bit from the IOM guidelines or even better fix the IOM DRIs and look at that process there. Pay more attention to the actual health outcomes that we do care about. That is something to work on within the government process and the committee will have to grapple with next time as well.
More dairy is a “double win” for Big Food and bad for Mother Earth
Willett continued:
There are consequences of this high consumption of dairy that is recommended. First of all, it’s naive to think that if you say ‘low-fat dairy’ that that fat is not going to be consumed. Actually, the dairy industry loves this recommendation because they take the fat out, sell the milk for the same price, and then they go sell the butter. It’s really a double win for them. That fat always gets consumed. Nobody’s flushing it down the drain. Maybe if the demand goes down, the price goes down, and it maybe be incorporated if it becomes really cheap into processed foods. But it’s actually still a premium product with a high price. So it’s going to get consumed no matter what you say about low-fat or fat-free dairy.
The other consequence is this is one area that does clash with the environmental recommendations. If we’re consuming now about 1.6 cups of dairy a day or equivalents then going to 3 would mean approximately doubling production of dairy products in the United States. Already dairy has a huge environmental impact. If we double that environmental impact, we’re clearly going in the wrong direction.
It’s amazing to look back and see what those two- to thee-week studies actually result in in terms of demand and production for dairy products in the United States.
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