(Bloomberg) – Sugary soda may worsen the effect of genes that put people at risk for obesity, according to one of several studies reported this month on how the drinks affect weight gain.
People genetically predisposed to obesity were more likely to gain weight from the beverages than those without the traits, according to the study, published last week in a New England Journal of Medicine theme issue. Other research showed that switching to a diet soda from a sugary one may help kids control weight gain.
One in three U.S. adults and 17% of children are obese. Sugary beverages are the largest single caloric food source in the nation, according to an editorial that accompanied the studies. This month, New York City limited the cup size that restaurants can use for sugary drinks, and schools across the country have banned the beverages.
“It is important to begin to create publishable studies to support what everyone knows,” said Steven Safyer, chief executive officer of Montefiore Medical Center in New York, who has worked to curb obesity in the city. “We are in the eighth inning of the worst public health crisis that we have encountered in decades.”
Obesity costs the country about $147 billion a year in health care expenses, according to the Centers for Disease Control and Prevention. If the country stays on the current course, it could increase the health costs by $66 billion a year by 2030, according to a report earlier this week by the Trust for America’s Health and Robert Wood Johnson Foundation.
Safyer said soda is particularly harmful when it comes to obesity because it doesn’t make people feel full, eliminating the normal triggers that stop people from eating.
To look at the connection between genetic risk and obesity, researchers from the Harvard University School of Public Health analyzed databases of more than 30,000 people to compare their consumption of sugary drinks with their genetic predisposition for becoming obese. Risk was based on mutations to 32 genes associated with body mass index.
A person is considered obese when their BMI is 30 or greater, which would be 215 pounds for someone five feet, 11 inches tall.
The obesity risk for those who drank more than one sugary drink a day was about twice as high as those who had less than one serving a month, said Lu Qi, an assistant professor at the Harvard school in Boston and the senior author on the study.
The researchers didn’t look at the link between genetic risk factors and other types of foods. The finding, though, provides evidence that genes and diet may mutually influence each other, Qi said in a statement.
“This study provides strong evidence that there is a significant interaction between an important dietary factor, intake of sugar-sweetened beverages, and a genetic- predisposition score, obesity and the risk of obesity,” said Sonia Caprio, a pediatrician at the Yale School of Medicine in New Haven, Conn., in an editorial in the journal accompanying the studies.
