The price of nutritious food is rising faster than less-healthy options, leading to a dietary disparity between the haves and have-nots, a new study shows.
That leads some researchers to conclude that it's time to rethink U.S. food policy, which through its subsidies encourage production of a limited range of foods that may not necessarily be part of a nutritious diet. Their report is published in the Journal of Epidemiology & Community Health.
University of Washington researchers previously found that better quality diets are more costly than less nutritious diets, and that there is a rising disparity in the price of healthful foods.
“The twist with this new study is that we’ve connected the dots that could explain why people in a lower socioeconomic status have less nutritious diets,” says Pablo Monsivais, acting assistant professor of epidemiology.
Seattle Obesity Study
Researchers studied data of more than 1,300 men and women from the Seattle Obesity Study, a population-based study of food access, diet quality, and health among King County, Wash. residents.
They first looked at how diet cost was associated with educational attainment and household income, two indicators of socioeconomic position. They used statistical methods to control for total calorie intake and other factors.
The average diet cost was higher for people with higher educational attainment and higher household income. People with lower educational attainment had diet costs that were an average of $1.09 per day lower than that of persons in the highest group ($8.19 to $9.28 per day).
Those with the highest educational attainment or income also enjoyed the most nutritious diets. Those in the highest income group reported diets that were on average 9.3 points higher in nutrient density than diets reported by the lowest income group (96.6 versus 87.3 percent), after controlling for dietary and demographic factors.
However, after taking the cost of food into account, the difference in dietary nutrient density between the highest and lowest groups shrank to 1.4 percentage points (93.0 versus 91.6 percent). “These results tell us that cost is a major factor in explaining the differences in eating habits between people of lower and higher socioeconomic level,” says Monsivais.
Monsivais says the Seattle study should be replicated on a wider, more diverse (in terms of education, income) section of Americans—or in another country.
Study results provide fodder for new and different nutrition policy and interventions, which for the last several decades have been mostly premised on the idea that poor diets were due to a lack of nutrition knowledge or insufficient motivation for healthy eating.
“The most universal policy change or intervention would be to rethink how we encourage the production of foods,” say the researchers. “In this country, we have a very expensive agricultural subsidy program that targets a limited range of foods that are not part of a nutritious diet. We do not support fresh produce or seafood, but instead support the production of inexpensive sugars, fat and refined grains. We need to align public health priorities with agricultural policies because it affects the largest number of people.”
In addition, Monsivais says states could be more creative with public school food programs and other nutrition efforts that affect low-income people. California has experimented with an electronic benefits transfer program (food stamps) that rewards people who buy fresh produce, which makes having a healthier diet easier and more affordable.
Food retailers and grocers could also help consumers make healthier choices, says Monsivais, by using “member” cards that can be used in a helpful and healthful way, offering up coupons for items that are nutrient-rich.