By Daniel Bonsangue
The US government has propagated nutritional guidelines since 1916.[1] Only since 1980, however, have the Dietary Guidelines for Americans been the cornerstone of nutritional policies and programs in the United States.[2] These guidelines are taught to children in public schools, and to future doctors, nutritionists, and dieticians in professional schools.[3] Yet, according to the Nutrition Coalition, the health of Americans has declined sharply in that time.[4] 74% of adults are overweight or obese[5], including 18.5% of all U.S. kids.[6] 18.2 million adults have coronary artery disease, 45% of American adults (4% of adolescents) have hypertension, 11% of Americans have diabetes, 35% have prediabetes, and 17% of women have osteoporosis.[7]
There is no question that, by almost every metric, the health of Americans has declined, and that decline is correlated almost exactly with the USDA’s release of the first food pyramid and subsequent guides. Whether there is a causal link between the government guidance and the health crisis is another question. The USDA maintains that the nutritional guidelines are based on sound science, and the problem is that Americans simply do not follow them well enough for them to work. Other groups, notably the Nutrition Coalition, contend that Americans do follow them, and that the guidance is faulty.
Public Law 101-445, 7 United States Code 5341 requires the Secretary of Agriculture to publish a report entitled “Dietary Guidelines for Americans” every five years, containing nutritional and dietary information and guidelines for the general public.[8] The information and guidelines in the report must be based on the “preponderance of scientific and medical knowledge which is current at the time the report is prepared”.[9] In other words, the dietary guidance is, at least in theory, based off of what the majority of experts are saying at the time.
In the 2020-2025 Dietary Guidelines, the USDA outlines the ways in which Americans have failed to follow the guidelines that they have put out. Citing the National Health and Nutrition Examination Survey data from 2005/6 to 2015/16, the USDA found that adherence to the Dietary Guidelines only reached 56-60 out of 100 on the Average Total Healthy Eating Index in any given year.[10]
The government recommends that half of daily grain intake should be from whole grain, that only 15% of daily calorie intake should come from added sugars and saturated fats, and more specifically that a healthy diet should consist only 10% of added sugars.[11] However, while most American meet recommendations for total grain intakes, 98% fall below recommendations for whole grains, and 74% of Americans exceed limits for refined grains.[12] 20% of Americans’ intake of refined grains comes from snacks and sweets, such as crackers, pretzels, cakes, cookies, and other grain desserts.[13] 13% of Americans’ diet consists of added sugars.[14]
While the USDA points to evidence that their guidelines would be effective if only the American people followed them, groups like the Nutrition Coalition point to evidence that the guidelines are flawed. A study in a journal of the National Academy of Sciences found that U.S. guidelines cannot be guaranteed to reflect trustworthy advice for combating obesity, diabetes, or any other chronic disease.[15] The National Academy of Sciences issued seven recommendations for the USDA to implement in order to remedy some of the issues in their guidelines, among those being the lack of public disclosure of conflicts of interest on the dietary guidelines committee, but the USDA did not implement six of them.[16] A Cambridge University Press publication reported that 95% of the members on the dietary guidelines committee did in fact have conflicts of interest with the food or pharmaceutical industry, notably Kellogg, Abbott, Kraft, Mead Johnson, General Mills, Dannon, and the International Life Sciences.[17]
Of course, conflicts of interest on the guidelines committee don’t necessarily translate to faulty guidelines. However, among the problems found in the guidelines process, the National Academy of Sciences publication found that guidelines on dietary fat, saturated fat, and cholesterol were either no longer supported by science or were simply in error.[18] Various studies would tend to support this conclusion. A 2020 study found that people who reduced their saturated fat intake were just as likely to die from heart disease and other causes as those who ate more saturated fat.[19] Another study in 2021 found that total saturated fat intake has no effect on the risk of heart disease, however certain foods high in saturated fat may impact heart health differently than others.[20]
The dietary guidelines about fats are not insignificant, mainly because of the implications that they have on other food groups. Meat, dairy, and eggs provide much of the total fat and saturated fat in the US food supply.[21] Encouraging the public to eat less of these things means that they will necessarily replace them with something else in their diets and, while the guidelines might recommend more vegetables, it is not farfetched to conclude that people have instead replaced the fats in their diets with carbohydrates. If the newer studies about fats are true, then they have replaced something that wasn’t all that harmful to begin with something that might be.
It is important not to take the approach of simply finding studies that contradict what the guidelines say and using them to support the argument that the guidelines got it wrong. Nevertheless, certain trends would tend to suggest that it is the guidelines themselves, not the fact that people aren’t following them, that are the root cause of the rising rates of chronic diseases. While the USDA points to data suggesting that Americans are eating too many refined grains and saturated fats and not enough whole grains, other data suggests that, since 1980, consumption of fresh vegetables is up 20%, fresh fruits up 35%, grains are up 28% and vegetable oils (the recommended fats) are up 87%.[22] At the same time, consumption of whole milk is down 79%, eggs down 13%, animal fats down 28%, and Americans are consuming 9% less butter, all in accordance with the guidelines.[23]
Particular issue is taken with the USDA’s treatment of carbohydrates. Critics point out that the guidelines committee did not consider low-carbohydrate diets, despite growing evidence that curtailing the consumption of grains and sugars in favor of meat, dairy, and eggs could improve and eliminate some metabolic diseases, and despite the fact that 80% of comments during the comment period while the rules were being considered talked about low-carbohydrate diets.[24] In addition, carbohydrate restriction is currently the only whole-foods approach that can reverse a diagnosis of Type 2 Diabetes.[25] So, given that grain is still the largest food category recommended in the most updated graphic, and given that people have followed that recommendation, these critics suggest that the guidelines have contributed to the onset of many of the chronic conditions plaguing Americans, and that reluctance to change these guidelines is hindering potential solutions.
It’s not clear which came first, the chicken or the egg. It is possible that the USDA has been disseminating faulty nutritional guidelines which, when followed by Americans, have contributed to burgeoning levels of obesity and chronic diseases. It is also possible, however, that with the increasing availability of sugary and processed foods, Americans’ dietary habits worsened, and the dietary guidelines have attempted to reverse that trend with limited success.
It is also possible that both of those things are true. The guidelines advise limiting added sugars, which are also recommendations that critics of the guidelines point to. The battleground appears to be the role of fats, particular animal and saturated ones, and carbohydrates that aren’t added sugars. It probably wouldn’t hurt for the USDA to at least consider diets that reflect emerging research on those food groups.
For the time being, however, it’s important for Americans to both follow the advice of experts while also maintaining a healthy level of skepticism and keeping their eye out for promising new information about how to eat.
[1] Food and Nutrition through the 21st Century, https://guides.lib.unc.edu/nutrition-history/government (last visited Jan. 31, 2023).
[2] Amanda Radke, Dietary Guidelines for Americans are a Failed Human Experiment: Radke Report, Farm Forum (August 3, 2022, 5:23 a.m.), https://www.farmforum.net/story/news/columnists/2022/08/03/federal-government-dietary-guidelines-failure/10212068002/.
[3] Id.
[4] Amanda Radke, Dietary Guidelines for Americans are a Failed Human Experiment: Radke Report, Farm Forum (August 3, 2022, 5:23 a.m.), https://www.farmforum.net/story/news/columnists/2022/08/03/federal-government-dietary-guidelines-failure/10212068002/.
[5] U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. https://www.dietaryguidelines.gov/.
[6] Amanda Radke, Dietary Guidelines for Americans are a Failed Human Experiment: Radke Report, Farm Forum (August 3, 2022, 5:23 a.m.), https://www.farmforum.net/story/news/columnists/2022/08/03/federal-government-dietary-guidelines-failure/10212068002/.
[7] U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. https://www.dietaryguidelines.gov/.
[8] Establishment of Dietary Guidelines, 7 U.S.C. §5341 (2023).
[9] Id.
[10] U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. https://www.dietaryguidelines.gov/.
[11] Id. at 37.
[12] Id. at 37.
[13] Id.
[14] Id.
[15] Cheryl Achterberg, et al., An Analysis of the Recent US Dietary Guidelines Process in Light of its Federal Mandate and a National Academics Report, PNAS Nexus, 1, 1- 12 (2022).
[16] Id.
[17] Mélissa Mialon et al., Conflicts of Interest for Members of the U.S. 2020 Dietary Guidelines Advisory Committee, Public Health Nutrition, (2022).
[18] Cheryl Achterberg, et al., An Analysis of the Recent US Dietary Guidelines Process in Light of its Federal Mandate and a National Academics Report, PNAS Nexus, 1, 1- 12, (2022).
[19] Lee Hooper, et al., Reduction in Saturated Fat Intake for Cardiovascular Disease, Cochrane Databased Systematic, National Institutes of Health, (2020).
[20] Marinka Steur, et al., Dietary fatty acids, Macronutrient Substitutions, Food Sources and Incidence of Coronary Heart Disease: Findings from the EPIC-CVD Case-Cohort Study Across Nine European countries. Trusted Source Journal of the American Heart Association, (2021).
[21] Marion Nestle, USDA’s Dietary Guidelines: Health Goals Meet Politics, (1992), https://www.foodpolitics.com/wp-content/uploads/DietaryGuidelines_CNI_92.pdf.
[22] Amanda Radke, Dietary Guidelines for Americans are a Failed Human Experiment: Radke Report, Farm Forum (August 3, 2022, 5:23 a.m.), https://www.farmforum.net/story/news/columnists/2022/08/03/federal-government-dietary-guidelines-failure/10212068002/.
[23] Id.
[24] Id.
[25] Id.