Adopting Greek, Japanese diets could reduce U.S. obesity
Americans could slim down and save significantly on health care expenditures if they ate more like people in Greece or Japan, according to a new study by University of Nebraska-Lincoln agricultural economists.
The UNL research compares the U.S. diet with those of Greece, Japan, France and Finland, considered in a consensus of literature as generally healthier diets. It appears to be the first study to examine health care costs and BMI effects in the United States by breaking down consumption patterns in nine key food categories by country.
Agricultural economist Sarah Rehkamp will present a preliminary report on the findings July 28 in San Francisco as part of the annual meeting of the Agricultural and Applied Economics Association and the Western Agricultural Economics Association. Abstracts for the conference were selected after a competitive process that includes peer review.
She found that even without cutting calories, Americans could trim their average Body Mass Index (BMI) by nearly 2.6 points, or 9 percent, if they adopted a Mediterranean diet like that eaten in Greece. The average American still would be overweight, but the switch could reduce national health care expenditures by an estimated 6.4 percent, or nearly $160 billion per year.
“People could reduce their BMI not only by reducing calories but by shifting the types of food they’re eating,” Rehkamp said.
If Americans also reduced calorie consumption to adopt a diet like that eaten in Japan, average BMI would be reduced more than 3 points (or nearly 11 percent) while reducing health care expenditures by 7.6 percent, or $190 billion per year, the study showed.
Rehkamp’s research was conducted as part of a five-year project by UNL Agricultural Economics Professor Azzeddine Azzam to study the environmental performance of local vs. conventional food systems, using Nebraska fresh vegetables as a case study.
“Her findings on how plant-based and animal-based components of diets affect BMI across countries are useful in measuring energy use and health costs of alternative diets here in our state,” Azzam said.
Rehkamp used data collected by the Organization of Economic Cooperation and Development, United Nations Food and Agricultural Organization, the World Bank and the World Health Organization to compare diet composition in the five countries.
Consumption was broken into nine categories, such as plant-based products, beef, dairy, fish and seafood, and poultry, to calculate their correlation with Body Mass Index. Consumption and BMI trends over 30 years were considered, along with factors such as food prices, internet users, smoking prevalence, hours worked and urbanization. The conclusions were based on 2009 consumption levels and results from the economic model. The impact on health care costs was based upon a 2006 study of 372,979 General Motors union workers, retirees and their spouses that found that health care costs per person increased by $202 for each one unit increase in BMI.
Rehkamp’s report is co-authored with Azzam and assistant professor Christopher Gustafson, who co-advised Rehkamp on the research. The July 28 report is derived from her master’s thesis, which also examined environmental cost savings from switching to healthier diets.
“This research provides an illustration of the real costs that our food choices impose on the economy, both through higher direct health care expenditures to treat obesity-related diseases, and through lower worker productivity,” Gustafson said.
Rehkamp is now an economist with the USDA’s Economic Research Service in Washington, D.C., although the conclusions of her study may not be attributed to the USDA or the Economic Research Service.
Overweight and obesity is increasing worldwide. The World Health Organization reported that 1.9 billion people worldwide were overweight in 2013, with 600 million qualifying as obese. Overweight is defined a BMI greater than 25; obesity is a BMI above 30.
The United States had the highest BMI of the countries Rehkamp studied — an average of 28.45 in 2009. Finland was at 26.25, Greece at 25.75 and France at 25.35. Only Japan, at 22.7, had an average BMI that would not be considered overweight.
Diets in both Japan and Greece rely more on plant products and less on red meat than the United States. Japan’s diet involves fewer calories and more fish than that in the United States, while in Greece, people eat more cheese and yogurt and less eggs, pork and poultry than in the United States.