When Is It Safe for Breastfeeding Moms to Begin Losing 'Baby Fat'?
At the end of the 10-week study, women in the diet and exercise group lost an average of over 10 pounds of their total body weight and almost nine pounds of fat mass compared with respective losses of almost 2 pounds and less than 1 pound in the non-exercise/dieting group. Body fat decreased by over 3% in the diet/exercisers, compared with almost no decrease in the other group. The average calorie decrease in the diet and exercise group was 544 calories per day compared with a decrease of 236 calories per day in the non-exercise/dieting group. The results are published in the Feb. 17 issue of The New England Journal of Medicine.
The average weight gain among infants was slightly less than 1 ounce per day for babies of mothers in the diet and exercise group, which Lovelady reports is similar to gains in the babies of the no-diet group. Average gains in length also were similar for all infants in the study.
However, in an accompanying editorial, a researcher from Baylor College of Medicine in Houston says although there were not major differences between the groups, the study was small and important differences can't always be seen except in larger trials. Nancy F. Butte, PhD, associate professor of pediatrics, says the study seems to confirm existing research showing that a moderate diet and exercise does not affect the quality of a mother's breast milk or her supply of milk, nor does it seem to affect the rate at which the infant grows, but she says more studies are needed to look specifically at breast milk changes in women who are dieting and exercising.
Another factor to consider is that giving birth and breastfeeding a baby bring changes to a woman's life and to her family that can be stressful and fatiguing. "I just think that four weeks is too early [to start trying to lose weight]," Butte tells WebMD. "Milk production is just getting established, and between all the stresses of adapting to a new child, it's a vulnerable time to start weight reduction." She advises that women who need to lose weight postpone a diet and exercise program until four to six months after giving birth, when breast milk is no longer the sole source of nutrition for the infant.