Battling obesity is not just about eating less and moving more, expert says

There’s more to losing weight than just eating less and moving more, according to Dr Claude Bouchard, who studies the genetics of obesity.

“When someone says of an obese person, ‘They should just eat less and exercise more’, I say if it were that simple, obesity wouldn’t be the worldwide epidemic that it is,” said Dr Bouchard, who is a faculty fellow of the Texas A&M University Institute for Advanced Study.

Dr Bouchard says there are dozens of factors involved in determining whether or not a person becomes overweight or obese.

“It’s a complex problem because there are so many drivers,” said Dr Bouchard. “Approaches focus on only a few and forget that while we control them there is compensation taking place elsewhere; there are other drivers that come into play.”

He divides these drivers into four categories:

• Social factors include less access to nutritious foods, more recreational eating, powerful and constant advertising, large food portions, poor school meals, eating on the run, food pricing and fewer meals cooked at home.
• Our physical environment - such as the absence of footpaths, reliance on automobiles, building design and environmental pollutants - affects eating habits, Dr Bouchard says.
• Behavioural factors such as spending less time in strenuous activity, taking medications known to increase body weight, the absence of breastfeeding, eating corn fructose syrup, an increase in sedentary jobs and high-fat diets.
• Biological factors such as genetics, viruses, gut microbiota (microorganisms living in the intestine), adipose tissue (body fat) biology and metabolic rates can all affect weight and many are not within a person’s control.

“The biology is very complex,” Dr Bouchard notes. “The response to environmental, social and behavioural factors is conditional on the genotype of an individual. Your adaptation to a diet or a given amount of exercise is determined by your genes.”

While more research is needed, Dr Bouchard anticipates that in the future diet and exercise programs for weight control or disease prevention will be tailored to an individual’s genetic make-up.

Dr Bouchard is director of the Human Genomics Lab at the Pennington Biomedical Research Center