Women aiming to shed after-pregnancy pounds should add daily walks and limit TV time and trans fats, according to a new study by Harvard researchers.
"The childbearing years are a time of particular risk for weight gain in women," said lead author Emily Oken, M.D. "Modifiable behaviors in that early postpartum period — such as diet, television viewing and walking — can influence a woman's risk of retaining weight."
Oken and colleagues evaluated data collected between 1999 and 2003 on 902 pregnant women along with their pre- and post-pregnancy weight, physical activity levels, dietary intake and television viewing habits.
The study is being published in the April issue of the American Journal of Preventive Medicine.
For each hour of walking they did daily, women had about a 34 percent lower odds of retaining 5 kilograms of weight — about 11 pounds — at one year.
"Most women retain a pound or two after pregnancy, but women who retain substantial weight are at increased risk of cardiovascular disease and obesity," said Oken, an instructor in ambulatory care and prevention at Harvard Medical School and Harvard Pilgrim Health Care.
The results showed that the more television a woman watched daily, the less likely she was to shed pregnancy-related weight. Women who consumed more trans fats — often found in shortenings, margarines, crackers and fried food — also proved more likely to retain weight during the postpartum period.
The benefits of each healthy behavior appeared additive. Women who watched fewer than two hours of TV daily, walked 30 or more minutes daily and ate fewer trans fats had a 77 percent lower odds of weight retention than women who did none of the beneficial behaviors.
Although the study "emphasizes the fact that pregnancy is a big factor in weight retention," said Raul Artal, M.D., professor and obstetrician/gynecologist at St. Louis University School of Medicine, he added that the population included mostly white, college-educated women with normal weight prior to pregnancy — a group generally characterized as being at low risk for weight problems.
However, the results should encourage pregnant or postpartum women to stay as active as they were pre-pregnancy, Artal said.
"Our findings aren't that you need to run marathons or be at the gym six hours a day. These behaviors are attainable for a lot of people, especially walking," whether with your baby in a stroller or on a treadmill at a gym, Oken said.