Policies that counter fast food consumption might offer governments a way to tackle the growing obesity epidemic, a new study proposes.
The research is the first to look at the effects of deregulation in the economy and increases in fast food transactions and BMIs over time.
The findings show that fast food purchases were independent predictors of increases in the average body mass index (BMI) in the United States and 24 other wealthy nations from 1999 to 2008.
Nations with stronger government regulations—such as producer protection, price controls, intervention on competition, and taxes—experienced slower increases in fast food purchases and average BMIs.
“Unless governments take steps to regulate their economies, the ‘invisible hand of the market’ will continue to promote obesity worldwide with disastrous consequences for future public health and economic productivity,” says Roberto De Vogli, associate professor in the department of public health sciences at the University of California, Davis.
Rather than looking at the density of fast food outlets or self-reported fast food consumption as researchers have done in the past, De Vogli and colleagues compared data on fast food transactions per capita with figures on BMI, a standard measure of body fat based on height and weight. A person with a BMI of 25 to 29.9 is considered overweight, while a BMI of 30 or more is considered obese.
Published in the Bulletin of the World Health Organization, the study focuses on high-income countries, but the findings are also relevant to developing countries as “virtually all nations have undergone a process of market deregulation and globalization—especially in the last three decades,” De Vogli says.
Unhealthy weight is widespread
While the average number of annual fast food transactions per capita increased from 26.61 to 32.76, average BMI increased from 25.8 to 26.4. Thus, each 1-unit increase in the average number of annual fast food transactions per capita was associated with an increase of 0.0329 in BMI over the study period.
The BMI figures revealed that the problem of unhealthy weight is widespread; people living in all 25 countries included in the study were, on average, overweight.
The average number of annual fast food transactions per capita increased in all 25 countries. The sharpest increases were in Canada (by 16.6 transactions per capita), Australia (14.7), Ireland (12.3) and New Zealand (10.1), Norway (9.0), and the US (8.6), while the lowest increases were in countries with more stringent market regulation, including Italy (1.5), the Netherlands (1.8), Greece (1.9), Belgium (2.1), Portugal (2.6), and Spain (3.4).
“It’s not by chance that countries with the highest average BMIs and fast food purchases are those in the forefront of market liberalization,” De Vogli says. “Whereas countries with lower average BMIs and fewer fast food transactions have some of the tightest controls on food economies.”
Increases in BMIs could not be explained by increases in animal fat consumption or total calories, which remained close to constant over the course of the study.
“This was surprising,” De Vogli says. “Fast food tends to be high in animal fats, which have been linked to unhealthy weight. The only factor that can partially explain the BMI increases is soft drink purchases.”
Future research should focus on categorizing food items according to levels of processing instead of fats and calories, which could help identify the specific determinants of overweight and obesity, De Vogli says.
“The next step will be to study in detail what is done with food and how those processes alter calorie and nutrient content along with health.”
Researchers from the University of Texas Health Science Center and Queen’s University in Belfast contributed to the study, which was funded by the Economic and Social Research Council in the UK.
Source: UC Davis