Is it Safe to Be on the Keto Diet While Breastfeeding?

Medically Reviewed by Dan Brennan, MD on April 17, 2023
3 min read

Giving your baby all the nourishment they need should be your top priority. If you are familiar with exclusive breastfeeding, then you know that your baby needs to feed on nothing else than breast milk for six months. Your milk contains all the energy, nutrients, and fluid your baby needs for healthy growth and development. It also protects your baby from infections and diseases and has long-term health benefits for both you and your baby. That is why it is important to eat a balanced diet while breastfeeding.

The keto diet is based on low-carb and high-fat intake, which causes your body to go into its ketogenic state, also known as ketosis. When your body is in ketosis, it uses fat stores for energy instead of glucose. This is a naturally occurring metabolic process, but one we don’t need to use very often anymore. 

Some of the foods you need to eat most while on the keto diet are meat, fatty fish, cheese, butter, and eggs. To remain in ketosis, you should avoid alcohol, sugary food, grains and starches, fruit, and unhealthy fats like mayo and vegetable oils. 

Cutting calories to lose weight can affect your milk supply. Although there is no evidence to show that a low-carb diet will affect your milk supply, most pediatricians recommend a balanced diet to benefit you and your baby. However, since most keto foods fill you up quickly, you may not eat enough to attain your daily caloric intake. As a result, your milk supply may decrease. A keto diet demands frequent hydration, and if you do not remember to stay hydrated, you may not produce enough milk for your baby.

Low-carb diets can cause a breastfeeding mother's body to release ketones that could pose risks for a baby. Ketones are chemicals made when the body does not have enough insulin in the bloodstream.  Serious illness and even comas can result when ketones build up too quickly in the bloodstream.

Possible side effects to the diet include “keto flu,” fatigue, muscle loss, bad breath, smelly urine, and some digestion issues. A low-carb diet can be dangerous to breastfeeding moms and has been reported to be life-threatening. 

On average, you can expect to nurse eight to 12 times a day. This is especially true in the early stages before your baby can get nutrients from solid food. The metabolic demands of breastfeeding will likely require more than your usual amount of calories. Based on a 2,000 calorie diet, you need anywhere from 200 to 300 extra calories every day to keep your baby well nourished. That is why it is common to lose some weight when you are nursing even if you are eating a balanced diet.


This condition is related to the metabolic changes and increased nutritional demands of producing milk. Although common in cows, the condition is very rare in humans but has been reported to send breastfeeding women to the emergency room. Ketoacidosis is mostly associated with diabetes, although it can be caused by starvation, drinking alcohol, and some medications. 

Dietary restrictions from pregnancy do not apply to breastfeeding moms. Here’s what you should eat to keep yourself and your baby healthy at all times:

  • Include whole grains such as whole-wheat bread, pasta, cereal, and oatmeal in your daily diet.
  • Eat two servings of fruit per day.
  • Eat three servings of vegetables, including dark green and yellow vegetables per day.
  • Drink enough water to satisfy your thirst.
  • If you don’t eat meat, ensure you eat other sources of iron and zinc such as dried beans, dried fruit, nuts, seeds, and dairy. If you avoid all animal products you will need to take a B12 supplement to ensure your baby does not develop a B12 deficiency.
  • If you want to drink alcohol, wait two or three hours after each serving (12 oz. beer, 6 oz. wine, 1.5 oz. liquor) before breastfeeding.
  • Include protein foods two or three times per day such as:
    • Meat
    • Poultry
    • Fish
    • Eggs
    • Dairy
    • Beans
    • Nuts  
    • Seeds 

The keto diet has its set of benefits. A balanced diet is even more beneficial. Since you are eating for your baby as well, it is advisable not to diet until you are done breastfeeding. Get all the necessary nutrients you and your baby need whenever you can.