Progress made over the past decade to improve the eating habits of U.S. adults has not narrowed racial and socioeconomic disparities, according to a new study.
Surveys conducted between 1999 and 2012 of self-reported dietary habits of more than 33,000 adults ages 20 and older found the percentage of Americans with what would be deemed as a “poor” diet decreased from 56% to 46% over the study period while the number of those with “intermediate” diets increased from 44% to 53%. The number of adults who were found to have “ideal” diets also increased but slightly from 0.7% to 1.5%.
Researchers defined “poor” and “intermediate” diets through scores calculated by the American Heart Association's 2020 Strategic Impact Goals.
The findings, published Monday in JAMA, identified several dietary improvements, including an uptick in the consumption of whole grains, nuts, whole fruits and fish, while decreasing the intake of sugar-sweetened beverages and 100% fruit juice.
“These findings may inform discussions on emerging successes, areas for greater attention, and corresponding opportunities to improve the diets of individuals living in the United States,” study authors wrote.
But the same dietary improvements were not found among black and Mexican-American adults. While the percentage of white adults with poor diets fell from 54% in 2003 to 43% by 2012, among black adults, the proportion with poor diets decreased from 65% to 58% in 2012 and 66% to 59% among Mexican-Americans during the same period.
Blacks and Mexican-Americans also had smaller spikes in the proportion of adults with intermediate diets. While the share of white adults with intermediate diets rose from 45% in 2003 to 56% in 2012, the number of black adults increased from 35% to 41%, while the number of Mexican-Americans with intermediate diets increased 34% in 2003 to 41% by 2012.
The study also found large disparities based on income and education level. Adults with a college degree and beyond had the largest decrease in poor diets, falling from 42% in 2003 to 33% in 2012. Adults with a high school diploma had the highest proportion of poor diets based on education level at 63% in 2003, while having the smallest decrease, falling to 58% by 2012.
Poor diet has been associated with the rise in a number of chronic conditions over the past two decades, including obesity, diabetes, cardiovascular diseases and diet-related cancers. In the U.S., health issues related to diet are estimated to account for more than 650,000 deaths per year and 14% of all disability-adjusted life-years lost.
The study's findings indicate what many experts feel is the impact socioeconomic factors such as poverty can have on dietary habits, and to a larger extent, health outcomes. Proximity to stores that sell fresh fruits and vegetables has been cited as one of the contributing factors that has led to lower income communities having higher rates of such chronic conditions as obesity, hypertension and diabetes.
“Access is a huge issue,” said Dr. Margot Denke, formerly with the University of Texas Southwestern Medical Center, who wrote a corresponding editorial to the JAMA study. “If you have fruits and vegetables that are more expensive than other choices, then you have two layers of barriers - you have access and affordability.”