Mom and Baby

Losing Baby Weight - Downfalls to Dieting While Breastfeeding

By: Sabrina Granniss, IBCLC

|

4 min

Pregnancy, childbirth, and breastfeeding are times of major and rapid changes physically and emotionally. During the nine months of growing your baby, your body changes shape and size. After giving birth, your body changes as hormones shift again, and you begin to nurse your baby or pump milk to give to your growing little one. Some changes may be welcomed and exciting, while others are uncomfortable or emotionally difficult. Many mothers wonder when they will lose the weight they gained during pregnancy, if they can diet, and if that will affect their milk supply.

It all adds up - what contributes to weight gain during pregnancy

  • By the end of your pregnancy, the placenta weighs about 1-1.5  pounds. 
  • Your body retains extra water during pregnancy. The increase supports cell function and oxygen delivery and helps flush toxins out. The volume of water you retain can be up to 8 liters (33 cups). (1) 
  • Plasma volume increases by 50%. (2) The primary role of plasma, which is the largest part of your blood, is to carry and deliver nutrients and hormones where they are needed in the body and to remove waste deposited in plasma from other cells. It supports your organs as they change and the growing needs of the placenta to support your baby as they develop.
  • Your baby’s weight is likely about 7-8 pounds by the end of your pregnancy.
  • Your uterus expands to accommodate your growing baby, and the muscle layer grows, adding about 2 more pounds.
  • Your breasts prepare to make milk to feed your baby after birth and gain anywhere from  1-3 pounds during pregnancy. (3)
  • Amniotic fluid weighs about 2 pounds. It cushions your baby while they move and grow in the womb.
  • 6-8 pounds is due to increased fat stores. This provides a reserve of calories for you and your baby during the rapid growth period during the last several weeks of pregnancy. Most of the stores are on your back, thighs, and belly. (4)

The amount of weight you gain during pregnancy depends on many factors. While there are guidelines for weight gain during pregnancy, an individual’s unique health history, diet, and lifestyle contribute to how much weight is gained while pregnant. 

Weight gain recommendations during pregnancy: (5)

  • Underweight - 28-40 pounds
  • Normal weight - 25-35 pounds
  • Overweight - 15-25 pounds
  • Obese - 11-20 pounds

Postpartum weight loss

It is typical to lose weight after the birth of your baby. You no longer have your little one on the inside, the placenta is delivered, and there is no more amniotic fluid. As you establish breastfeeding, it is recommended not to focus on additional weight loss. The average amount of weight retained postpartum is 2.5-5 pounds, and ¼ of women will keep 11 pounds or more. (6) Weight seems to stabilize between 6-12 months postpartum.

Breastfeeding burns approximately 300-500 calories if you are exclusively breastfeeding.

The best approach to weight loss during breastfeeding is to focus on nutrition and exercise or movement. In one study, women who exclusively breastfed for 3 months lost significantly more weight than people who didn’t exclusively breastfeed during the first three months postpartum. The World Health Organization recommends exclusive breastfeeding for the first 6 months of a baby’s life. (7)


Extreme diets or exercise regimens can negatively impact your nutrition and, therefore, affect your milk. Your nutritional status impacts your gut health, affecting the milk you make. Excessive exercise can temporarily increase lactic acid in breast milk, giving it a more bitter taste, but this seems to be short-lived. (8) Moderate exercise does not cause the same result and has shown no negative impacts on the baby or parent. When you restrict calories too much or are not eating nutritiously dense foods, your milk supply can decrease.

Recommended total daily postpartum caloric intake (10)

  • Sedentary: 1,800 - 2,000 calories
  • Moderately active: 2,000 - 2,200 calories
  • Active: 2,200 - 2,400 calories

Healthy ways to lose weight while breastfeeding

  • Eat whole foods that do not come in a package. Whole foods are full of nutrition and contribute to better overall health. Eat the rainbow- including lots of colorful, fresh vegetables and greens in your meals.
  • Continue to take your prenatal vitamins to ensure you get all the vitamins and minerals necessary for you and your baby.
  • Drink plenty of liquids to replace fluids lost when you sweat during exercise.
  • Breastfeed before exercising so you are more comfortable during your workout.
  • Your body may have changed and need extra time or support to avoid injury while exercising. Pay attention to what your body is telling you. Start slow with exercise and work up to more intensity as your body is ready.

Legendairy Milk’s breastfeeding supplement ingredients are herbs that support milk production, add nutrition, and are Fenugreek-free. Some moms and babies experience stomach discomfort from fenugreek, and Fenugreek should not be used if you have a thyroid imbalance.

Why am I not losing weight?

Your hormones go through significant shifts during pregnancy, birth, and breastfeeding. Suppose you find you have gained weight or just aren’t able to lose it after your baby arrives, despite trying. In that case, you may need to get in touch with your IBCLC (International Board Certified Lactation Consultant) to dig in deeper and uncover possible reasons why. Sometimes hormones are out of balance after having your baby. There are often indicators before your pregnancy, but they may not have been significant enough to be picked up on before now. Postpartum thyroiditis often surfaces during the first year postpartum. (9) Changing the foods you eat will help improve gut function, which helps balance hormones and can improve thyroid function. (10)


Improvements to overall health are longer lasting and become a new lifestyle that you, your baby, and the whole family can benefit from. Exercise can reduce stress and increase your energy levels, giving you more energy to play with your baby. It contributes to better sleep and a happier state of mind.


Weight gain during pregnancy is a combination of various factors. After childbirth, it is normal to lose weight gradually, and breastfeeding can aid in calorie burning. If your goal is to lose weight while breastfeeding, focusing on nutrition, exercising in moderation, and listening to your body's needs is helpful. Embracing a healthy lifestyle supports weight management and enhances overall health and well-being for both mother and baby.

Shop

Related Blogs

Footnotes

References

Leave a comment