A cross-sectional analysis found that U.S. adults who had a higher consumption of foods derived from subsidized food commodities had an increased risk of some cardiometabolic risk factors.
They had a greater probability of having a body mass index (BMI) of at least 30 kg/m 2, a ratio of waist circumference to height of at least 0.60, a C-reactive protein (CRP) level of at least 0.32 mg/dL, an elevated non-high-density lipoprotein cholesterol level and dysglycemia. However, they had no increased risk of high blood pressure.
Lead researcher Karen R. Siegel, PhD, of the Centers for Disease Control and Prevention in Atlanta, and colleagues published their results online in JAMA Internal Medicine on July 5.
The researchers evaluated 10,308 nonpregnant adults between 18 and 64 years old who participated in the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2006. The participants consumed between 800 and 5,000 calories per day.
The mean age of participants was 40.2 years old and 50.5 percent were males.
The researchers derived a subsidy score derived from the seven major subsidized food commodities: corn, soybeans, wheat, rice, sorghum, dairy and livestock. The scores ranged from 0.0 (zero percent of total energy from subsidized commodities) to 1.0 (100 percent of total energy from subsidized commodities). They estimated the score using NHANES dietary recall data and federally sponsored linked databases.
The participants consumed 56.2 percent of their calories from the major subsidized food commodities. Participants who ate the highest proportion of subsidized foods were younger They also had a higher proportion of Mexican Americans and a lower proportion of non-Hispanic whites and non-Hispanic blacks compared with those who ate the lowest proportion of subsidized foods.
Participants in the highest proportion group also tended to be significantly less educated, poorer, less food secure, had increased rates of smoking and decreased rates of leisure time physical activity compared with participants in the lowest proportion group.
“Adjusted for sociodemographic and lifestyle factors, being among the highest quartile of subsidized food consumers was associated with having a 14 to 41 percent higher probability of cardiometabolic risk as measured by BMI, abdominal adiposity, CRP level and lipid levels,” the researchers wrote. “These associations remained robust to adjustment for overall diet quality.”
The study had a few potential limitations, according to the researchers, including that they assessed diet and created the subsidy score using a single day of 24-hour dietary recall in the NHANES. However, they also said the 24-hour recall provided more specific detail than a food questionnaire.
They added that they could not calculate the amount of high-fructose corn syrup in foods or the proportion of subsidized meat consumed. Further, the study’s cross-sectional design did not allow the researchers to determine causality.
“We have not demonstrated that the agricultural subsidies themselves are responsible for the current cardiometabolic risk burden in the United States, but rather that agricultural subsidies are one part of the entire panoply of cardiometabolic risk factors, some of which include poverty, cheap food, poor dietary choices and fewer options,” they wrote.
The researchers estimated that it costs between $150 million to $300 million per year to treat obesity-related cardiometabolic diseases in the U.S., which is more than the government spends on farm support or nutrition assistance programs. If obesity was eradicated during the five years of this study, they estimated Medicare spending would have been 8 percent lower and Medicaid spending would have been 12 percent lower.
“Although eating fewer subsidized foods will not eradicate obesity, our results suggest that individuals whose diets consist of a lower proportion of subsidized foods have a lower probability of being obese,” they wrote. “Nutritional guidelines are focused on the population’s needs for healthier foods, but to date food and agricultural policies that influence food production and availability have not yet done the same.”