While regular exercise is a key to good health, obesity isn't surging because people aren't working out enough. Instead, researchers are placing the blame on diets loaded down with excess sugar and carbs.
In an editorial published in the British Journal of Sports Medicine, researchers busted the idea that it's possible to stave off the effects of a bad diet by working it off in regular physical activity.
"In the past 30 years, as obesity has rocketed, there has been little change in physical activity levels in the Western population," they wrote. "This places the blame for our expanding waist lines directly on the type and amount of calories consumed."
The research showed [pdf] that up to 40 percent of people at a normal weight will still develop metabolic abnormalities usually connected to obesity.
Researchers liken the food industry's PR tactics to those of Big Tobacco — which employs denial, doubt, confusion and unsound science to mislead the public into believing that smoking doesn't cause lung cancer and other health problems.
"Celebrity endorsements of sugary drinks and the association of junk food and sport must end," they said, adding that gyms and health clubs must also set a good example by doing away with excessive sugar and carbs in their locations.
Large-scale messages about public health have focused mostly on promoting healthy weight by sticking to a low number of calories. But rather than just counting calories, it's important to factor in where the calories come from. The researchers pointed out that sugar calories encourage hunger and fat storage while fat calories promote satiation or fullness.
Carbs were also targeted in the editorial, with evidence suggesting that they aren't much better. In fact, recent studies have indicated that reducing excessive dietary carbohydrates is the single best way to cut back on the symptoms of metabolic syndrome — making the move possibly the most effective strategy to address diabetes.
The researchers suggest that the food environment has to change, to create a society in which people will automatically make healthier choices.
"Healthy choice must become the easy choice" to have a more effective impact on improving the population's health, working better than education or counseling.
"It's time to wind back the harms caused by the junk food industry's public relations machinery," the researchers wrote, calling for a better understanding of the relationship between exercise and obesity.
"You can't outrun a bad diet," they concluded.
Around the world, obesity rates have more than doubled since 1980. In 2014, over 600 million adults 18 years old and up were obese.
Photo: Uwe Hermann | Flickr