Researchers looked at the body mass injuries of one million women after childbirth, and measured how breastfeeding affected the index over time.
Karen Procker is pregnant with her third child. She is pregnant with her third child, and has breastfed after each pregnancy.
"Children who are breastfed are sick less, and they have less allergies. The longer you do it, the better it is," says Procker.
For mothers, too says the study.
The study found nursing mothers had a one percent reduction in BMI for each six months of breastfeeding. It also dropped their risk of obesity decades later.
BMI is a number which takes height and weight into account in order to calculate body mass index.
"The study is very exciting because it shows that immediately post partum a woman slims down, but it s a long lasting effect throughout a woman's period of life," says Dr. Mary Rosser, M.D., Ph.D.
The internet can help find your BMI. Several sites allow you to enter height and weight. Over 30 is obese.
A one percent reduction in BMI may not sound like much, but it translates into 10,000 fewer deaths from obesity related illnesses such as diabetes, heart disease and cancer.
Perhaps this is because women who breastfeed make healthier food choices and keep them throughout life, says Dr. Rosser, along with healthier lifestyle choices. With each child, a woman gains some weight. The study found it was offset by breastfeeding. Procker saw the effect.
"I did notice that I didn't gain weight but it did help to lose the baby fat quickly," she said.
Dr. Rosser says that 75% of new mothers breastfeed right after birth, but that at 6 months, only 13 percent are still doing it. Several medical organizations recommend the practice out to six months.
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