What the potato study says about how you can avoid creeping weight gain

Most people think that “everything in moderation” is the key to maintaining a healthy weight, but findings in a new study published in the New England Journal of Medicine suggest otherwise.

Having an extra serving of soda each day could result in putting on about a quarter of a pound each year, said Dr. Dariush Mozaffarian, an associate professor of epidemiology and the first author of the study. Likewise, cutting back consumption of such high-calorie drinks could help people gain less weight.

People realize that their pesky love handles didn’t appear overnight, but few can pinpoint the root cause of their weight gain. Now they have access to information that can point them in the right direction. The findings in the New England Journal study can act as a road map to a healthier lifestyle for people who want to head off gradual weight gain, though it may be less relevant for obese patients trying to lose weight, experts said.

“The study, which confirms a lot of common-sense advice that we promote through health programs, gives the average citizen a targeted strategy to control weight gain,” added Dr. William Dietz, director of the Division of Nutrition, Physical Activity and Obesity at the Centers for Disease Control and Prevention.


For example, people know to avoid sugary and high-fat foods if they want to slim down, but most would not consider potatoes or fruit juice beach-body saboteurs. But the researchers found that a daily serving (six to eight ounces) of 100% fruit juice put people at risk of gaining a third of a pound every four years. Potatoes helped people put on roughly the same amount each year.

The study “highlights the value of eating real foods,” said Dr. Jeffrey Schwimmer, the director of the weight and wellness program at Rady Children’s Hospital in San Diego. But he warned people against trying to oversimplify the data: “Someone might say, ‘Well, look, adding an extra serving of dessert every day only accounts for a 0.4-pound increase every four years.’ But we know that’s not accurate.”

Nevertheless, he thinks that the data presented in the study will be useful both for public policy-makers as they consider taxing high-calorie foods like soft drinks and for average middle-aged adults worried about weight gain and developing cardiovascular disease and diabetes down the line.

The take-away point then, as Mozaffarian explains it, is “that small changes can make a big difference -- for bad or good. Eat more minimally processed foods and fewer starches and refined foods. Be active, turn off the TV, and get enough sleep.”