US Dietary Guidelines for Americans—101
What are the US Dietary Guidelines?
For nearly 40 years, the U.S. Departments of Health and Human Services and Agriculture have jointly issued the Dietary Guidelines for Americans (DGA), the principal policy guiding nutrition in the United States. That stated goals are to promote good health, prevent chronic disease, and help Americans reach a healthy weight.
What do the Dietary Guidelines Recommend?
The core recommendations of the Guidelines state that a healthy diet for all Americans should include vegetables, fruits, grains (half of which should be whole grains), low or non-fat dairy, and a variety of protein foods, including seafood, lean meats and poultry, eggs, legumes (beans and peas), and nuts, seeds, and soy products. Further, Americans are told to keep saturated fat content below 10% of calories (why the DGA recommends lean meat and low or non-fat dairy), added sugars below 10% of calories, and salt below 2300mg per day.
Read here about concerns by scientists that a number of these recommendations are not based in sound science.
The Dietary Guidelines specifically recommends three “Dietary Patterns”:
How did the Dietary Guidelines begin?
The first Guidelines were launched in 1980, based on a 1977 report by the Senate Select Committee on Nutrition called, Dietary Goals for Americans. The Senate report recommended that Americans should consume less fat (particularly saturated fat), less dietary cholesterol, and more grains, fruits and vegetables. This is basically the same advice that we have today.
This Senate report later came under scrutiny, as it was written by a single staffer who favored vegetarianism.
“It was Senator George McGovern’s bipartisan, non-legislative Select Committee on Nutrition and Human Needs — and, to be precise, a handful of McGovern’s staff members — that almost single-handedly changed nutritional policy in this country and initiated the process of turning the dietary fat hypothesis into dogma.” — Science Magazine, 2001
It’s hard to overstate what a radical departure from the government’s stand on nutrition the Dietary Guidelines for Americans represented when it first came out in 1980. Since 1956, the USDA had been advising people to seek out nutritious foods by eating a “well-balanced” diet of the basic food groups - first five of them, then seven, then four. The four food groups were milk, meat, fruits & vegetables, and cereals & grains. American had been encouraged to eat some foods from each group every day. The USDA has always suffered from a conflict of interest, since it entire mission is to promote American food commodities, and the agency has long been heavily influenced by those very industries.
— Nina Teicholz, The Big Fat Surprise
Early reviews, including one by the National Academy of Sciences, cautioned that the evidence on saturated fats and heart disease was not conclusive. Then-president of the Academy, said in Congressional testimony, in 1980:
Why are the Guidelines important?
The Guidelines exert extraordinary influence on American eating habits. The advice dispensed to each and every American from doctors, nutritionists, dieticians and other health professionals invariably comes directly from the Guidelines. Advice from professional associations (American Medical Association, American Diabetes Association, etc.) also derives from the Guidelines. Thus, even though you may know nothing about the Guidelines, they reach you through your health professionals.
The Guidelines also dictate government nutrition assistance programs, which touch one in four Americans every month (they are the single-biggest expense at the US Department of Agriculture). These include:
The Guidelines direct FDA regulations on food, including the information on packaging. For example, the Guidelines inform health claims (whether a food can be advertised as “healthy”) and the information listed on the back of the package (the “Nutrition Facts” panel). [Note: can we include a picture of nutrition facts panel here]
In summary, more Guidelines are undoubtedly the single-most influential lever on the our food supply as well as our ideas about what constitutes a healthy diet.
Are the Guidelines working?
Since the introduction of the DGAs, however, there has been a sharp increase in nutrition-related diseases, particularly obesity and diabetes, that the DGAs have been unable to stem.
There has been widespread criticism about the lack of scientific evidence behind the Dietary Guidelines.
What is the current state of concern?
In 2015, Congress mandated the first-ever outside peer review of the Dietary Guidelines, by the National Academy of Sciences, Engineering, and Medicine. The report, Redesigning the Process for Establishing the Dietary Guidelines for Americans, was published in September 2017. Report excerpts:
- “To develop a trustworthy DGA, the process needs to be redesigned.”
“The current DGA process for reviewing the science falls short of meeting the best practices for conducting systematic reviews.”
“Methodological approaches and scientific rigor for evaluating the scientific evidence need to be strengthened.”
“The adoption and widespread translation of the DGA requires that they be universally viewed as valid, evidence-based, and free of bias and conflicts of interest to the extent possible. This has not routinely been the case.”
“The methodological approaches to evaluating the scientific evidence require increased rigor to better meet current standards of practice.”
This report endorses the concern that has been expressed by many experts about both the science underlying the DGAs as well as the process used to draft them. Some of these issues are outlined here. The science behind the guidelines is not settled, and Congress is concerned.
Nutrition Evidence Library. The United States Department of Agriculture’s (USDA) Nutrition Evidence Library (NEL) is an entity that specializes in conducting systematic reviews (SRs) to inform Federal nutrition policy and programs. The systematic reviews compiled for the 2015 DGA are available here.