The New York Times revealed earlier this week that Coca-Cola was behind the Global Energy Balance Network, a research group that addresses obesity with a single-minded focus on physical activity.
The Times compared the group’s work to that of the small group of scientists who accepted funding from Big Tobacco to conduct studies that introduced doubt into an otherwise clear picture of the health effects of smoking.
The comparison was aggressive because it’s not unusual for nutrition or physical activity researchers to accept funding from major food conglomerates — however unsavory that reality may be. The Academy of Nutrition and Dietetics, for instance, also gets financial support from Coca-Cola.
But the arrangement between Global Energy Balance Network and the soft drink giant crosses a line by advancing a view of weight and metabolic health that falls outside the scientific consensus, experts told Healthline.
Exactly how much the global rise of obesity is connected to inactivity and how much it owes to unhealthy eating habits remains the topic of rich scientific debate. But there are few scientists who would describe poor eating habits as simply eating more calories than one burns, according to Dr. Bruce Lee, director of the Global Obesity Prevention Center at Johns Hopkins University.
“We know that there are organizations and movements and groups that focus on all one thing. For example, the American Council on Physical Fitness focuses on physical fitness,” Lee said. “That’s fine. When you start trying to say that something is a greater cause of obesity, that’s potentially when we get into a problem.”
The explosion of obesity and type 2 diabetes in the United States is linked to a number of trends, which include reduced physical activity, shoddy sleep habits, and a diet that includes more processed foods and less whole grains and vegetables.
“It’s more useful to really say obesity is a trend. We need to look at all the different parts of that trend and how we can reverse it,” Lee said.
What the Numbers Show
The “energy balance” hypothesis — that obesity is simply a matter of calories in minus calories burned — makes space for the argument that soda can form part of a healthy diet for people who are active.
But that’s just not the case, experts told Healthline.
With 140 calories in a 12-ounce can, a one-soda-a-day habit would require an extra hour a day of walking or 36 minutes every other day of lap swimming. But Americans continue to struggle to meet the minimal physical activity guidelines.
Soda isn’t the only product that doesn’t fare well when exposed to such mathematical calculations. A vigorous half-hour workout burns about 15 percent of the recommended daily calories for a moderately active adult of average size.
A number of studies have used different methods to see what happens when people exercise more without making changes to their diet. One showed that after a year of regular exercise, men who exercised had lost just a few pounds.
“The evidence for eating less as a weight-loss strategy is much, much stronger than the evidence for moving more,” said Marion Nestle, Ph.D., a professor of nutrition at New York University and the author of the forthcoming book “Soda Politics: Taking On Big Soda (And Winning).”
“The idea that you can eat all you want as long as you are active sounds nice — nobody wants to have to eat less — but it’s highly unlikely to work.”
Not All Calories Are Created Equal
Nutritionists have two problems with sodas: Sodas don’t have any nutritional advantages and they pose unique nutritional challenges.
“In public health terms, [sugary beverages] are low-hanging fruit,” Nestle said. “They contain sugars — lots of sugars — water and not much else and have no redeeming nutritional value.”
Sugary beverages may also be especially harmful.
Fructose, found in fruit, cane sugar, and high-fructose corn syrup, is more likely to lead to metabolic conditions such as type 2 diabetes and fatty liver disease than glucose.
Sugar added to processed foods, including soda, comes in one of these fructose-bearing forms, which accounts for the new move to require “added sugars” to be identified on food labels.
Fruit also contains fructose, but it also has fiber, which slows down digestion. Fruits contain vitamins and phytochemicals that help the body handle fructose. They also take longer to eat.
Gulping down an icy cold soft drink can deliver 39 grams of added sugar in a matter of seconds.
“The issue is the sugars,” Nestle said. “A 12-ounce soft drink has 10 teaspoons of sugar. That’s a lot for the pancreas and liver to deal with.”
A recent study blamed sugary drinks for 180,000 deaths in 2014.
Boiling down the global obesity epidemic to a simple equation of calories in and calories out overlooks important health facts that could help people make better lifestyle choices.
The “energy balance” approach backed by Coca-Cola “does oversimplify what the situation is,” Lee concluded. “The issue of improving physical activity is important, but it doesn’t overrule the continued need to really look at what people are drinking and eating.”