Research has shown that breastfeeding moms can safely lose one and a half pounds a week, through exercising or weight loss diets. If you lose more than that, it is more likely that your own health will suffer than that your milk supply will be endangered. The key to healthy weight loss during the breastfeeding period is dropping your calorie intake gradually rather than abruptly, and to weight with going on a diet until your milk supply is well established, which is when your baby is around two months old. Besides a weight loss diet, being physically active also helps you return to your pre-pregnancy weight and body. Remember that gaining good muscle tone again, particularly in the abdominal area, is just as important as losing your pregnancy weight.
The nice thing is that mothers can lose weight while jogging with their baby in a stroller or baby carrier, and catch five minute power work outs during naps or while someone else holds the baby. While people say that it really takes a full nine months to recover from pregnancy, that doesn't mean it will take nine months for you to look like your old self again!