Health & Science blog

By Rebecca Knight

Should we treat foods high in sugar and saturated fat – such as French fries and soda – like cigarettes and liquor, and subject them to a “sin” tax?
 
Some health advocates think so, and this week a study that appears in the Archives of Internal Medicine, one of the JAMA/Archives journals, provides some pretty persuasive scientific evidence to support such a measure. The study, conducted by researchers at the University of North Carolina at Chapel Hill, found that if junk foods were subjected to a “fat tax” people would eat them less and lose weight as a result. 
 
Here is a link to an extract of the study: Food Price and Diet and Health Outcomes subscribers to the journal may access the article here too
 
In the study, designed to identify risk factors for cardiovascular disease, researchers tracked the diet and weight of 5,115 young adults over a 20-year period. Participants’ height and blood levels of glucose and insulin were also collected, as well as a measure of insulin sensitivity. Food price data were compiled for the same timeframe.
 
Over the period, a 10 per cent increase in price was associated with a 7 per cent decrease in the amount of calories consumed from soda and a 12 per cent decrease in the amount of calories consumed from pizza.

A one-dollar increase in the cost of soda or pizza was also associated with a lower overall daily calorie intake, lower body weight and an improved insulin resistance score, and a one-dollar increase in the cost of both soda and pizza was associated with even greater changes in these measures.

The researchers estimate that an 18 per cent tax on these foods would result in a decline of roughly 56 calories per person per day. These declines would amount to weight loss of approximately 5 pounds per person per year, with corresponding reductions in the risk of obesity-related diseases, they note.
 
“Our findings suggest that policies to alter the price of less healthful foods and beverages may be one possible mechanism for steering US adults toward a more healthful diet,” the authors write. “While such policies will not solve the obesity epidemic in its entirety and may face considerable opposition from food manufacturers and sellers, they could prove an important strategy to address overconsumption, help reduce energy intake and potentially aid in weight loss and reduced rates of diabetes among US adults.”