2015 Dietary Guidelines for Americans: The Good, the Bad and the Ugly
By Dariush Mozaffarian, MD, DrPH Dean, Tufts Friedman School of Nutrition Science & Policy
Earlier this year, the federal government released the new Dietary Guidelines for Americans (DGAs). (See our March Special Report.)
As a cardiologist, public-health advocate and nutrition scientist, I see a lot of good in the DGAs.
First, the DGAs emphasize healthful eating patterns and foods. This is an advance over past guidelines, which focused more on isolated nutrient targets. Modern nutrition science tells us that, for preventing major diseases like obesity, diabetes, heart disease and cancers, it’s all about food choices and overall diet patterns, not single nutrients.
Second, the DGAs state that all segments of society have a role to play in supporting healthy choices. In other words, it’s not just about personal willpower, education or food labeling: Everyone needs to pitch in, including the healthcare system, food industry, local and national governments, community organizations, religious groups and corporate America. While cynics might dismiss this as fancy speech-making, at least the government is saying, officially, that the burden of healthy eating cannot fall only on the consumer.
Third, the DGAs make a clear, up-front declaration: "All food and beverage choices matter." This could seem a minor point. But it actually represents a pretty strong antidote to the notion that we can overlook unhealthy choices, that eating junk is no big deal, that all we need to do is eat "everything in moderation." This last questionable concept, strongly supported by the food industry, would have us believe that all the junk in the food supply fits in somewhere. (See the February newsletter.)
The idea that all choices matter is a cornerstone of public health. People and populations gain or lose health not by isolated, extravagant actions, but by gradual accumulation of small, daily choices and actions. Think of your health as a long-term savings account. You can try to win the lottery and get rich quick, but a better approach is slow, steady savings over your lifetime.
Few parents I know would purposefully remove their own seatbelts, or take their children out of car seats, once a week or once a day. While the risk associated with these single acts is tiny, it adds up, over months to years, into large and entirely preventable risk. Yet, these same folks will eat a hot dog, donut, soda, flavored chip or sugary cereal, or feed these to their kids, like it's no big deal. The risk associated with any of these actions is arguably larger than removing one’s seatbelt for a drive. Don't do it, or at least do it with eyes wide open. Kudus to the 2015 DGAs: All food and beverage choices matter.
INCONSISTENT, CONTRADICTORY: Now, the bad. Several aspects of the DGAs are inconsistent or contradictory. First, while the DGAs appropriately omit any specific limit on total fat (a strongly evidence-based improvement), much of the specific guidance around foods remains highly fat-phobic.
For example (and we'll put aside, for now, the emphasis on low-fat dairy, lean meats and even lean poultry - heaven forbid someone ask for dark meat at Thanksgiving), the DGAs correctly recommend more vegetable oils in the diet, but also inexplicably warn, "they are a concentrated source of calories," "the amount consumed should be within the [old dietary limits] for total fats," and "oils should replace solid fats rather than being added to the diet."
On nuts, the DGAs warn, "because they are high in calories, they should be eaten in small portions and used to replace other protein foods rather than being added to the diet." Long-term cohorts and controlled trials have disproven the idea that fat makes one fat, or that nuts or vegetable oils cause obesity, while showing that vegetable oils and nuts reduce heart disease and diabetes. Healthy foods are healthy - high fat or no fat - no caveats needed.
Next, while the scientists advising the DGAs concluded that saturated fat is no different than total carbohydrate for heart disease, both they and the 2015 DGAs remain heavily focused on reducing saturated fat. Judging a food or diet by its saturated fat content is not very useful, can be manipulated by industry, and is inconsistent with the appropriate new emphasis on foods and diet patterns. The saturated fat focus, a relic from the past, should have been put to rest.
Third, the DGAs say that healthy foods and diet patterns are crucial, yet simultaneously recommend "variety" and eating in an "adaptable framework" that meets one's personal and cultural "preferences." Such guidance sounds positive, yet in practice can easily be translated as "eat a bit of everything, including the bad stuff" - and this indeed is where the DGAs go. What happened to "all food and beverage choices matter"?