New Dietary Guidelines: A Physician's Perspective

Better late than never, we close out the first month of 2011 with the 2010 Dietary Guidelines for Americans. Released Monday, the guidelines are an update to those issued in 2005. As before, the guidelines begin with the recommendations of a Dietary Guidelines Advisory Committee, composed of scientists, but end as the federal agencies in charge of them -- USDA in particular -- see fit. This makes the guidelines a hybrid of scientific and political imperatives.

Overall, these Dietary Guidelines are more alike than different from their predecessors. In terms of the content changes, I like the new emphasis on obesity and chronic disease prevention/treatment.

Nutrition guidance is, inescapably, culture-bound: where there is starvation, more calories are good; where there is hyperendemic obesity, more calories are bad. These guidelines place a very clear emphasis on the reality of current U.S. epidemiology, and couch dietary guidance in that context. It makes sense to attempt to fix what's broken.

However, providing different guidelines for different people in the population based on chronic disease presence or risk does add a level of complexity that will likely make it a little harder for the public, and even some health professionals, to translate the guidelines into a personalized plan.

The new guidelines still lump cholesterol together with saturated fat, which I find to be entirely at odds with virtually all recent research on the topic. I don't know whether this was laziness, or inertia, or ... what, but it does not reflect a rigorous review of the science.

The guidelines make passing reference to 'plant based' diets, but repeatedly and explicitly encourage consumption of dairy and various meats. The content is certainly not balanced, and a stronger indication that mostly -- or even completely -- plant based diets can provide optimal nutrition was probably warranted.

The recommendation for seafood is confusing, even to me, given the emphasis on restricting dietary cholesterol. My patients have long been confused by this: do I eat shrimp, or not? The summary here seems very apt to confound this confusion. I agree with the inclusion of seafood, and as noted, disagree with the continued emphasis on fretting over dietary cholesterol.

There are some items in this report that clearly invite mischief. We have already seen, since the '05 guidelines, a proliferation of 'good source of whole grain' claims on food packages. The trouble with such messaging is that it is not holistic: good source of what else beside whole grains? Good source of whole grains compared to what?

These guidelines will propagate such practices. In addition, they specifically recommend foods fortified with vitamin B12. It's not very difficult to anticipate the sudden spate of 'fortified with vitamin B12 as recommended in the 2010 Dietary Guidelines!' messaging that will populate the fronts of boxes and bags.

The new guidelines suggest 'carving out' stearic acid from the saturated fats that should be restricted, and I think this is, if anything, overdue. The science has long shown that stearic acid -- the predominant saturated fatty acid in, for instance, dark chocolate -- is innocuous. I like the stearic acid carve out, but in the summary at least, there is no mention of where it is found, or how to take the general guidance -- 'avoid saturated fat but not stearic acid'-- and turn it into food choices! Good idea, but questionable execution.

There still appears to be the heavy hand of food industry/supply side priorities reflected in the repeated recommendations to include dairy and various meats. There could be -- but is not -- an explicit statement that a diet can exclude dairy and still be optimal, and here's how ... Or, that a diet can exclude meat and still be optimal, and here's how ... Encouragement of all "food groups" is likely a bow to food industry interests.

In fact, it's as if the ghosts of 'food groups past' from vintage dietary guidance are still haunting today's guidance. As if there is a concern about failing to represent any particular sector in the food industry. This, to me, is a clear indication of mission contamination, or conflict of interest -- with the dietary guidelines being mostly about public health, but also a bit about maintaining cordial relations between the government, and the behemoths of the agri-food world.

Closely related to the above, I also still find that the new guidelines, as all prior versions, are more explicit about what to eat than about what not to eat. Advice about what to eat includes foods -- advice about what 'not' to eat is generally limited to categories of foods, or even just nutrients. There is no reason why the guidelines couldn't say: "eat less of foods such as..." and provide a very explicit list. But you don't see that here. That has always been a deficiency in the guidance, and looks to be again -- for fairly obvious reasons.

With all that said, the content here is a slight improvement on prior guidelines, because it is only an incremental change, and the adjustments that do appear make these recommendations more current.

But perhaps the true, key considerations as we assess the utility of the new Dietary Guidelines come courtesy of Albert Einstein, and Gertrude Stein.

Einstein told us the definition of insanity was "doing the same thing over and over again, and expecting different results." I suppose, then, the greatest mind of the modern age may be saying that releasing dietary guidelines every five years that don't tend to affect how Americans actually eat is a little bit ... crazy. There are both simple, freely available programs -- and new, powerful ways to empower people to identify and choose foods that are truly more nutritious -- but the guidelines are pretty much mum on the topic.

Gertrude Stein told us: "a difference, to be a difference, must make a difference." Content 'differences' between the '05 and '10 (well, '11 really!) Dietary Guidelines don't really matter at all if they are not genuinely conducive to some salutary shift in actual eating patterns.

The report calls for a comprehensive array of policies and programs that would provide the 'how to' partner for these 'what to' guidelines. But we have seen such pleas before -- most notably from the IOM (Institute Of Medicine). And thus far, we have a lot more smoke than fire in this area.

Until we do all that is necessary to make truly more nutritious food readily available, identifiable, affordable, palatable, convenient, and ubiquitous -- dietary guidelines may make very little difference. In which case, the differences between this version and the last may not constitute a meaningful difference at all.

Dr. David L. Katz;