WASHINGTON — Many Americans are like a loaf of bread — soft, with one side round. Their choice of bread may be part of the reason.
Some researchers say white bread and other refined grains seem to go to the gut and hang out as belly fat.
“Waist circumference was very much associated with this high-refined grains pattern,” said Katherine Tucker, an associate professor of nutritional epidemiology at Tufts University in Boston. She and other scientists are studying what happens to the bodies of people who eat lots of refined bread.
The researchers have tracked the eating habits of a group of healthy, largely middle-age people in Baltimore. The focus is on 459 people with a variety of eating habits. Some prefer refined grains; others favor whole grains, fruits and vegetables.
The Tufts researchers say calories from refined grains like to settle at the waist.
The belt size of the white bread group expanded about one-half inch a year,which probably put some of the research subjects into a larger size of pants over the three years they were tracked, Tucker said. At the end, the white bread group had three times the fiber group’s gain at the gut.
It is not surprising that the waists of refined-grain eaters expanded, said Dr. David Ludwig, director of the obesity program at Children’s Hospital in Boston.
Ludwig was not connected to the Tufts study, but his research involving younger adults had found something similar. One of the factors he checked was the waist-to-hip ratio — whether people’s torsos were more tapered or more round. People who ate less fiber were rounder.
For consumers, white versus whole grain is not necessarily an either-or choice. About 70 percent of households have a white bread eater and about the same percentage have a whole wheat eater, according to a February report by the Mintel Group.