Scientists and public health officials have suggested that sugary drinks are one of the key environmental causes of obesity. Research has also identified genes that heighten the risk of obesity in the people who have them. A new study has found that for people with a genetically predisposed risk for obesity, sugary drinks increase the expression of their obesity genes.
Obesity, genetics and environment
According to the Centers for Disease Control & Prevention, genetics, as well as the environment are principal drivers of the obesity epidemic. A common explanation is that humans bear “energy-thrifty genes” that evolved when food sources were scarce and unpredictable. These genes that helped our ancestors survive through famine are being thrown out of whack by an environment where food is cheap and plentiful.
Everyone has at some of the 32 gene variants that have been associated with obesity. Obesity genes promote fat accumulation by driving people to overeat and conserve energy with a sedentary lifestyle. They may also diminish the ability to burn fat for fuel and enhance the storage capacity of body fat.
Sugary drinks and obesity genes
Sugary drinks are the single biggest source of calories in the American diet and they take much of the blame for the obesity epidemic. The U.S. has seen a parallel rise in the consumption of sugary drinks and obesity rates in the U.S. Both have more than doubled since the 1970s.
For people who are genetically predisposed to obesity, a new study from the Harvard School of Public Health has found that drinking a lot of sugary beverages could worsen their condition by enhancing the effects of their obesity genes.
Sugar and gene expression
The genetic obesity research was part of a series of health studies that have gone on for decades across the U.S. Researchers say it proves that drinking sugary beverages affects the expression of obesity genes, which increases someone’s risk of obesity more than it would be simply from heredity.
Researchers checked more than 33,000 volunteers for the gene variants that have been linked to obesity. Every four years, the participants completed questionnaires about their lifestyle and eating and drinking habits. After several decades, researchers found that for every 10 obesity genes someone had, their risk of obesity rose in proportion to how many sugary beverages the person regularly drank. Calorie intake and lifestyle factors such as smoking and exercise did not account for the pattern that emerged.
Quitting sugary drinks
If you have a genetic predisposition for obesity, it doesn’t guarantee you will become obese. But the study suggests that if you drink a lot of sugary drinks, chances are you will. The good news is that another study from Boston Children’s Hospital shows simply quitting sugary drinks could virtually guarantee weight loss.
Researchers recruited more than 200 overweight or obese high school kids in the Boston area and sent them shipments of either their favorite sugary drinks or sugar-free alternatives every two weeks. The kids received no nutrition advice and no effort was made to increase their physical activity. One year later, the group who drank sugar-free drinks weighed an average of four pounds less than those who kept consuming sugary drinks.
Healthy lifestyle trumps heredity
Everyone carries some genetic risk of obesity. But obesity isn’t destiny for those who are predisposed. Fortunately, the risk can be offset by a healthy lifestyle. Other research has shown that physical activity lowers the risk of obesity, even in people who are genetically susceptible. In this case, exercise, healthier beverage choices and a healthy diet can overcome heredity.
Source: USA Today, MedPage Today, Centers for Disease Control & Prevention