"People often say that healthier foods are more expensive, and that such costs strongly limit better diet habits," lead author Mayuree Rao of HSPH says in a news release
. "But, until now, the scientific evidence for this idea has not been systematically evaluated, nor have the actual differences in cost been characterized."
For this analysis, the team examined 27 existing studies from 10 high-income countries, including price data for individual foods. They evaluated the differences in prices in four ways: per serving, per 200 calories, per day, and per 2,000 calories (the recommended average daily calorie intake for adults) for overall diet patterns.
They found that healthier diet patterns -- for example, diets rich in fruits, vegetables, fish, and nuts -- cost significantly more than unhealthy diets (for example, those rich in processed foods, meats, and refined grains). The highlights:
- Meats and protein had largest price differences. Healthier options cost $0.29 per serving more than less healthy options.
- Price differences per serving for healthier vs. less healthy foods were smaller among dairy, grains, snacks/sweets, and fats/oils, and not significant for soda/juice.
- Comparing extremes, healthier diets cost $1.48 per day more than the least healthy ones.
Over the course of a year, however, eating a healthy diet would increase costs by $550 for just one person. "This would represent a real burden for some families, and we need policies to help offset these costs," says
study co-author Dariush Mozaffarian of Harvard
. "On the other hand, this price difference is very small in comparison to the economic costs of diet-related chronic diseases
, which would be dramatically reduced by healthy diets."
The team concludes that best way to make healthier foods more affordable is for governments to subsidize healthy foods and tax unhealthy ones, New Scientist reports
. New York, for example, is attempting this with sugary beverages
It comes down to the food industry and their economies of scale. According to the news release
Unhealthy diets may cost less because food policies have focused on the production of “inexpensive, high volume” commodities, which has led to “a complex network of farming, storage, transportation, processing, manufacturing, and marketing capabilities that favor sales of highly processed food products for maximal industry profit.” Given this reality, they said that creating a similar infrastructure to support production of healthier foods might help increase availability -- and reduce the prices -- of more healthful diets.
Image: J. Fang