Blog | Wednesday, March 11, 2015

Diet, dog and dogma

The release of the 2015 Dietary Guidelines Advisory Committee report does not officially give us new dietary guidelines for Americans just yet. Famously, there is a political element to this process. The scientists making up the advisory committee do just that: they advise. What actually emerges as guidance is determined by the federal agencies in charge, the U.S> Department of Agriculture and the Department of Health and Human Services.

Over the years, though, as the involvement of politics in our official dietary guidance has become ever more transparent, thanks at least partly to the efforts of Marion Nestle after chairing 1 such advisory committee, they have also tended to become a bit less heavy-handed. When the report of the scientists is circulated on the Internet, as it now is, the alterations made by politicians are visible to everyone who cares. That makes any serious adulteration of the scientists' recommendations something of an embarrassment, and rather a liability.

That doesn't mean there won't be any changes. Before the committee report is translated into official guidelines, there is a period of public comment, which is a banner that flies over a host of agendas. Some of the commentary will be from public health advocates, but much will be from industry. What exact dietary guidelines will emerge from this gauntlet remains to be seen.

But given that, I like what I see so far. I think the advisory committee has done a stellar job.

Their report runs to 572 pages, so I confess I have by no means read every word yet. But I have been through it enough to get the gist, and the gist is: wholesome foods, in sensible combinations. Amen to that!

Specifically, the report uses this language: “The overall body of evidence examined by the 2015 DGAC identifies that a healthy dietary pattern is higher in vegetables, fruits, whole grains, low- or non-fat dairy, seafood, legumes, and nuts; moderate in alcohol (among adults); lower in red and processed meats; and low in sugar-sweetened foods and drinks and refined grains. Additional strong evidence shows that it is not necessary to eliminate food groups or conform to a single dietary pattern to achieve healthy dietary patterns. Rather, individuals can combine foods in a variety of flexible ways to achieve healthy dietary patterns, and these strategies should be tailored to meet the individual's health needs, dietary preferences and cultural traditions. Current research also strongly demonstrates that regular physical activity promotes health and reduces chronic disease risk.”

This is really good stuff. The consensus of the scientists on the committee is, basically, that the theme of healthful eating is clear, but that there is no single variant on that theme that is the obvious choice for all. I like that conclusion both because it is true, and because it leaves people the latitude required to wind up loving the food that loves them back, as my own family does.

The emphasis on plant foods is based both on the body of evidence related to human health, and quite appropriately, on considerations of sustainability. As I addressed inmy prior column, whatever the potential merits of a meaty, Paleo diet, they are impractical for a huge population of humanity on a shrinking planet. The Dietary Guidelines for Americans now serve an audience of over 300 million people, and that must figure in the recipe. There is no healthy diet for healthy people on a seriously unhealthy planet. A section in the advisory committee's report devoted to sustainability is a very welcome addition.

In the fullness of its many pages, the advisory committee report does of course get into the nutrient particulars. The news was leaked in advance of the report release that the current committee has dropped the recommendation for restricting dietary cholesterol intake. That is indeed true, and as I have noted in a prior column, justified in my opinion.

There has been much debate lately about appropriate thresholds for dietary sodium, and the committee was clearly attentive to it. Their conclusion, again appropriate in my opinion, is that most Americans still get more sodium than is good for us, and efforts to reduce prevailing intake should continue. Since roughly 80 percent of the sodium in the typical American diet comes from processed foods, rather than the family salt shaker, a shift to less processed, and more home-prepared foods in general, rather than a fixation on sodium per se, is the right strategy.

Given all the recent noise regarding saturated fat, to which the committee members were most certainly not deaf, one might have expected some change in direction on the topic. There was none, and I again think the committee got it right. Despite the hype, no studies have shown health benefits of increasing saturated fat intake; they have, at best, indicated that when we replace an excess of saturated fat with an excess of sugar and refined starch, we are going sideways. In contrast, intervention trials with both Mediterranean and plant-based diets low in saturated fat have been shown to slash rates of heart disease. The committee thus retained saturated fat as a nutrient of concern, suggesting we limit our consumption. Again, however, the right response is about foods, not nutrients. There is no health benefit in reducing saturated fat by eating Snackwell cookies. There is for most of us a decisive health benefit if we eat less baloney, more broccoli and more blueberries.

The multidisciplinary committee was charged with looking at dietary components from the proverbial soup to nuts, and did just that. Unlike the seemingly competing factions in our culture at present, they felt no obligation to choose one nutrient focus over another. The recommendations rightly recognize the harms of excess sugar and refined starch, while also noting the liabilities of excessive intake of meat, processed meat especially. The recommendations also rightly ignored the distorted arguments and evidence-shopping that have landed books advising against wheat and grains on best-seller lists, but which are belied by the weight of evidence viewed without such bias. To my knowledge, the word “gluten” does not appear in the report.

Finally, there is a certain emphasis in the report on family. Personally, I would have liked that to be even greater, but it's pretty good. The committee clearly recognized the importance of shared, family dietary practices, and the potential advantages of family meals. A cultural emphasis on families eating well together will speed the dawn of the day that “dieting” dies, and good riddance to it. In the Blue Zones, they don't diet, they live it. They eat well, in traditional patterns, and live longer and better than the rest of us as a result.

The work of the 2015 Dietary Guidelines Advisory Committee is, in a word, excellent.

We likely still have a long way to go reorienting our culture to a renunciation of quick-fix diets, and an embrace of the tried-and-true fundamentals of healthful eating. In an age of polarized opinions, magnified in the echo chambers of cyberspace, there are a lot of competing dogmas to overcome. Getting past that, and coming together, is an important mission, but perhaps a topic for another day. For today, we at least now have recommendations, and the promise of official guidelines, that emphasize wholesome foods in sensible combinations, rather than isolated nutrients, which for far too long have unbalanced our diets, like a tail that wags the dog.

David L. Katz, MD, FACP, MPH, FACPM, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care. He is a board certified specialist in both Internal Medicine, and Preventive Medicine/Public Health, and Associate Professor (adjunct) in Public Health Practice at the Yale University School of Medicine. He is the Director and founder (1998) of Yale University's Prevention Research Center; Director and founder of the Integrative Medicine Center at Griffin Hospital (2000) in Derby, Conn.; founder and president of the non-profit Turn the Tide Foundation; and formerly the Director of Medical Studies in Public Health at the Yale School of Medicine for eight years. This post originally appeared on his blog at The Huffington Post.