Consumption of sugar-sweetened beverages like soda and energy drinks may be linked to as many as 184,000 adult deaths each year worldwide, according to research published today in the journal Circulation.
"This is a single dietary factor with no intrinsic health value causing tens of thousands of deaths per year," said study coauthor Dr. Dariush Mozaffarian, dean of the Friedman School of Nutrition Science & Policy at Tufts University. "It's time to remove sugary beverages from the food supply."
To get a handle on consumption of sugary beverages, Mozaffarian and his colleagues looked at information from 62 dietary surveys from 51 countries as well as data on the national availability of sugar from 187 countries. The surveys included data collected from 611,971 individuals between 1980 and 2010.
The researchers focused on sugar-sweetened sodas, fruit drinks, sports and energy drinks, sweetened ice teas and homemade sugary drinks such as frescas, that contained at least 50 kcal per serving. Beverages that were 100 percent fruit juice were excluded.
For information on the impact of sugary beverages on health problems such as BMI, diabetes, cardiovascular disease and cancers, the researchers turned to meta-analyses of other published studies linking health harms to sugar-sweetened drinks.
The researchers estimated that in 2010 sugary drinks may have been responsible for 133,000 deaths from diabetes, 45,000 deaths from cardiovascular disease, and 6, 450 deaths from cancer.
The effects of sugar-sweetened beverages varied widely depending on how popular they were in a particular demographic and country. For example, the estimated percentage of deaths attributable to sugary drinks in Japanese people over age 65 was less than one percent, while it was 30 percent in Mexican adults younger than 45.
Mexico, in fact, had the highest rate of deaths related to sugary beverages, with an estimated 405 deaths per million adults (24,000 total deaths) and the United States had the second highest, with an estimated 125 deaths per million adults (25,000 total deaths).
The high consumption of sugar sweetened beverages in Mexico and in Latin American countries could be due to problems finding safe drinking water, the researchers noted.
In a statement, the American Beverage Association, a trade group representing soft drink manufacturers, said the study "does not show that consuming sugar-sweetened beverages causes chronic diseases."
"The authors themselves acknowledge that they are at best estimating effects of sugar-sweetened beverage consumption," said the statement. "America's beverage companies are doing our part to offer consumers the fact-based information and the beverage options they need to make the right choices for themselves and their families."
Some might argue that the study doesn't prove beyond a doubt that soda is causing all those deaths because it's not a randomized controlled trial.
"You could say that this isn't perfect, but I think that if the beverage industry says we're not sure that soda causes obesity, they're just putting their heads in the sand," Mozaffarian said. "And we're not including all the other health impacts, like back pain, gallstones, joint disease, that are caused by obesity."
The researchers fear that the problem is only going to get worse since these kinds of beverages are more popular with younger people.
Dr. Bruce Lee hopes that the study will heighten awareness.
"People should be looking more carefully at what this consumption is doing," said Lee, an associate professor of international health and director of the Global Obesity Prevention Center at Johns Hopkins University. "Here you have a beverage where there isn't anything on the label to suggest any nutritional value. This is an easy target."
"The study is not a randomized controlled trial, so one can't be certain that it was the sugar-sweetened beverages causing the deaths," said Liz Ruder, a professor of nutrition and dietetics at the University of Pittsburgh Medical Center. "But because the authors have employed sophisticated statistical techniques and they have rich food consumption data I believe that these data are likely to be accurate."
While there is some controversy over sugar substitutes, Mozaffarian would rather see people consuming drinks with artificial sweeteners than with sugar. "You can view it as a bridge to success," he said.
Mozaffarian is hoping for changes at the governmental level and points to a recently released report showing how much sugar intake has declined in Mexico since the country adopted a sugar tax. "I think that shows that there is a really easy policy lever to pull that raises revenue while solving health problems."
Back in March of 2013, news media reported on an early version of the study that was presented at that year's American Heart Association Council on Epidemiology and Prevention meeting.