Among U.S. adults, Americans are eating healthier overall yet still don’t come close to meeting recommendations for whole grains, vegetables and other foods that play a role in preventing cancer, as well as heart and other chronic diseases. The findings come from a study published in The Journal of the American Medical Association that span the 13 years from 1999-2012.
The study examined data from a nationally representative sample of almost 34,000 adults who had filled out one of the seven National Health and Nutrition Examination Surveys (NHANES) from 1999-2012. Participants recalled what they had consumed over the past 24 hours. Researchers then broke that down according to food groups and nutrients. Diets were broken down according to targets from the American Heart Association (AHA).
As a whole Americans have increased consumption of whole grains and lowered intake of sugary beverages, two dietary habits that can lower cancer risk. Other positive dietary trends included a slight increase in fish and whole fruit, along with a decrease in sugary beverages by one-half serving per day (see chart). No significant change was seen for many other food categories, including vegetables, processed meat, saturated fat, or sodium.
Even with the improvements, intake remains far lower than recommended. For example, even though adults increased their whole grain consumption by a half serving per day over the 13 years, this is far less than than the three to five servings of whole grains per day recommended by the Dietary Guidelines for Americans. (Foods containing fiber, found in whole grains, links to reducing risk of colorectal cancer.)
Diet scores improved for both men and women and across all ages, with older adults having better diets than younger adults. Based on three categories of those meeting the AHA goals, the estimated percentage of adults with poor diets dipped from 56 to 46 percent. Those meeting 40 to 80 percent of the goals, having an intermediate diet, increased from 44 to 53 percent.
The percentage with ideal diets — adhering to at least 80 percent of the goals—nudged up but remained low (0.7 percent to 1.5 percent).
Disparities in diet quality were seen by race/ethnicity, education, and income level. For example, the estimated percentage of Americans with higher incomes eating an intermediate diet increased by almost 15 percent (from 49 to 63 percent) over the 13 year period. There was only a 6 percent increase (from (32 to 38 percent) seen among those in the lowest incomes eating an intermediate diet.
Several limitations of this study to note include self-reported intake and using only a daily, rather than weekly or monthly intake, which may lead to smaller observed changes over time.
Getting people to eat right is not a simple task, writes Margo A. Denke, M.D., author of an accompanying editorial. “Even though there has been some improvement from 1999 to 2012, clinicians, patients, and the food industry all need to work together to meet the challenge of improving the healthiness of the U.S. diet.”
The study was supported by a grant from the National Heart, Lung and Blood Institute
Sources: Dariush Mozaffarian, MD, DrPH et al. Dietary Intake Among US Adults, 1999-2012. JAMA, June 2016.
Margo A. Denke, MD. Changing Dietary Habits and Improving the Healthiness of Diets in the United States. JAMA, June 2016.