Your Ultimate Guide To Intermittent Fasting While Breastfeeding

Last Updated on March 28, 2023 by Jada Glover

Have you considered intermittent fasting while breastfeeding? Recent claims say it can help you in shedding extra pounds. It may work for some women, but as a breastfeeding mother, it’s important to consider many factors before you begin any fasting protocol.

I have personal experience with intermittent fasting while breastfeeding my 2-year-old son. I started when he was about a year and a half old, and I’ve enjoyed all the amazing health benefits, but I also know it’s not for every mom. Before starting any new lifestyle or diet, be sure to consult with your doctor first.

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Intermittent Fasting – An Overview

Intermittent fasting is a form of fasting in which you consume food during a specific period of time during the day and fast during the other part of the day. This form of fasting is well known among women as a way of reducing body fat and extra weight.

There are different types of intermittent fasting. You can choose which type suits you best based on your health goals, lifestyle, work-life, and of course if you are breastfeeding. Some people fast at night, starting at 7 p.m. and only eat food for a few hours of the day, from 12 p.m. – 7 p.m. as an example. This would be a 16 hour fast, with an 8-hour eating window, sometimes referred to as a 16:8 fast.

Another example is an 18 hour fast, with a 6-hour eating window, or an 18:6 fast. Some only eat food for a few days of the week and eat very few calories during the remaining days (I don’t recommend this form of fasting for breastfeeding mothers).

Studies show there are many benefits of fasting such as reducing body inflammation, blood sugar level, and reduced blood cholesterol. Some studies also show that when cells are under stress due to fasting, they resist the development of dangerous diseases.

Intermittent fasting may help in weight loss because when your body is not getting energy from eating food constantly, it starts breaking the extra fat molecules that your body had stored earlier. When you keep fasting for a few days or weeks, this process continues, which eventually reduces your weight. However, different people notice different results of weight loss due to fasting.

Can You Do Intermittent Fasting While Breastfeeding?

The short answer is yes, when done correctly and when your milk is regulated (usually about 3 months after delivery). The key to fasting while breastfeeding is doing it intermittently. You don’t want to extend your fast beyond 18 hours (24 at the very most, but I don’t recommend that until your baby is at least a year old and you are not your baby’s main form of nutrition).

It is equally important that you consume enough calories during your eating window- not going any lower than 1,800 calories for a 24 hour period. You typically use 300-500 calories to make milk, so you will likely need even more calories depending on other maternal factors (2,000-2,400 calories for nursing a single baby, more calories if you are nursing twins).

Starting slow and easing into it with high-quality, nutrient-dense foods will be the key to a healthy and sustainable intermittent fasting experience while breastfeeding. You want to focus on eating grass-fed meats, pasture-raised poultry, wild-caught seafood, organic fruits and vegetables, whole or sprouted grains, and nuts and seeds as much as possible. Your body will attain the most nutrients from real foods, which means you will have the energy and calories needed to produce milk and care for the baby.

What is the Effect of Fasting While Breastfeeding?

There are many factors to consider when starting any new diet or exercise regimen. There will always be positive and/or negative effects on you or your baby. It’s important to consider your health, previously and going forward, as well as that of your baby. If you ever feel unsure about fasting while breastfeeding, please consult your doctor and trust your motherly instincts.

Impact on Mother’s Health

Even though it’s not widely discussed in the lactation community, women have been intermittent fasting while breastfeeding for years. There are no severe issues associated with it when consuming quality, nutrient-dense foods during your eating window, and not fasting for more than 24 hours.

According to research, if a woman does not eat a proper diet when she is not fasting, she may face an issue regarding milk production. Always work with your medical provider to ensure it is safe for you.

Breastfeeding moms should eat an additional 300 to 500 more calories during their eating window so their bodies have enough calories when they are fasting. If you eat nutritious food, then your body will automatically adjust while fasting.

However, breastfeeding might make you feel weak, dizzy, thirsty, or you may have dark yellow urine. If you face any of these situations, then it is advised that you break your fast and drink coconut water or water mixed with electrolytes. Rest up, take care of yourself and your baby, and continue breastfeeding. You will feel better soon.

Sometimes the above symptoms are a result of the detoxing process, so here are a few tips if you experience any adverse reactions. These have helped me when I started intermittent fasting while breastfeeding.

• Start with a larger eating window (12 hour fast, 12-hour eating window, then reduce your eating window as you feel comfortable)
• Drink electrolytes
• Slowly reduce your eating window as your body adjusts.
• This shouldn’t be a detoxing or “crash” diet, as those toxins can make their way into your breastmilk, which is not healthy for your baby.
• You can try a “dirty” fast, which means drinking coffee with heavy cream, half and half, or Nutpods (dairy-free creamer) in the morning. The key is not to have more than 1-2 cups of coffee and make sure there is no sugar in your coffee.
• Listen to your body and adjust as you need to, this is a learning process and a lifestyle, not just a “diet”.

Impact on Baby’s Health

Fasting will not affect the growth of your baby if you eat well when you break your fast. Research shows that fasting may not affect the macronutrients present in the milk, but it may affect some of the micronutrients.

The calorie level in milk varies from mother to mother. It even varies from time to time within the same mom. If you are not taking in calories due to fasting, your body will automatically start using your stored fat to provide the needed calories to the baby.

The quantity and quality of your milk will not change if you intermittent fast like I’ve described in this post (a fast less than 24 hours). It is likely that your baby will get enough milk.  However, if you notice any of the following changes in the behavior of your child know that he or she is not getting the required quantity of milk, then it may be time to stop fasting, and eat a meal with healthy fats, protein, vegetables, or fruits.

• Your baby is either losing or not gaining any weight.
• Your baby is sleeping more than usual.
• Baby is dehydrated, even after feeding.
• Your baby does not have enough wet and dirty diapers.

If you notice any of these changes, then consult your doctor to find the cause behind it, keep an eye on your baby and milk supply, and revisit intermittent fasting at a later date.

How Long Can You Fast While Breastfeeding?

Unfortunately, there is very little scientific research on this topic. But experts say that fasting for up to 24 hours does not affect breast milk production in any way. However, if a mother fasts for more than that, then the quality and quantity of milk may get affected. I’ve seen a few testimonials where moms go longer than that, but it is not advisable as you and supporting your health and your baby’s health, and it’s truly not worth the risk.

Types of Intermittent Fasting

There are other common types of intermittent fasting, but these are not recommended while breastfeeding, unless you use them in conjunction with the 24-hour rule where you do not fast for more than 24 hours. This will also be affected by your personal health goals and your breastfeeding goals.

Fast for a set number of hours each day: This is the easiest and the one that I recommend, especially for beginners because you are sleeping for the majority of your 12-hour fasting window (or whatever fasting window you choose).

Alternate-Day Fasting: This type of fasting allows you to eat normally on non-fasting days, but you then restrict the number of calories consumed on fast days to no more than 1,800 calories.

5:2 Plan: This plan is similar to alternate-day fasting. During five days of the week, you will eat normally, and on the other two days of the week, you restrict the number of calories consumed to no less than 1,800 since you are breastfeeding. Your fasting days should not be consecutive days.

Intermittent Fasting While Breastfeeding Sample Schedule

There are multiple ways you can begin intermittent fasting while breastfeeding. I always suggest moms start slowly by changing their diet to include more healthy foods, such as high-quality proteins, fats, fruits, and vegetables. Do this for at least 3-4 weeks to see how you feel first and to get your body used to eating better quality foods. This will allow you to get the most nutrients out of the food you are eating and give your baby the best nutrition also.

Below are samples of an intermittent fasting while breastfeeding schedule by fasting for a number of set hours each day. Keep in mind what your health goals are, how long you’ve been breastfeeding, and if you’re the main source of your baby’s nutrition. All of those should be considered before deciding how aggressive to be with your fasting schedule. If you’re feeling uneasy, lightheaded, dizzy, be sure to eat something and drink electrolytes. You can always restart when you’re ready.

Since some moms also like to follow a ketogenic or low carbohydrate diet while breastfeeding, I also included a few sample diets with similar eating windows. Remember to still consume the number of required calories (at least 1,800 calories per day) during your eating window. Although it’s best to allow your body time to digest between meals, you can add a few snacks to meet your calorie requirements if needed (during your eating window).

Intermittent Fasting While Breastfeeding Sample Schedule

12-hour fasting window, 12-hour eating window (include electrolytes if this is new to you)

Meal One- Vanilla chia pudding with 1/2 cup of berries

Meal Two- Ginger chicken salad with broccoli slaw

Meal Three- Chicken chili or traditional chili

Snacks (as needed)- Healthy protein bars like Lara bars or RX bars

16-hour fasting window, 8-hour eating window (add electrolytes when this eating duration is new to you)

Meal One- 1 cup of oatmeal with honey and walnuts, 1/2 cup of berries

Meal Two- Green cobb salad with baked salmon or chicken, include lots of healthy fats (avocado, olive oil, boiled eggs) and yummy toppings to make it more filling

Meal Three- Mexican casserole with ground beef, or enchiladas

Snacks (as needed)- Grassfed beef sticks, cheese stick and sliced cucumbers

18-hour fasting window, 6-hour eating window (add electrolytes when this eating duration is new to you)

Meal One- 2 eggs, half an avocado, 1 cup of berries, 1 slice of whole-grain toast, sliced tomatoes

Meal Two- Tuna, chicken, or egg salad sandwich on whole-grain bread, with lettuce and tomato, 1 piece of fruit, 1/2 avocado

or Meal Two- Baked salmon or chicken with rainbow veggies, including cherry tomatoes, olives, potatoes, and asparagus

Snacks (as needed)- Fruit with raw nuts or seeds, raw trail mix

If you have a shorter eating window, you will need to eat more during your two meals of the day.

Pro Tips to Follow When You’re Intermittent Fasting While Breastfeeding

I started intermittent fasting when my son turned about a year and a half old. I would not recommend any fasting protocol if your milk isn’t regulated yet. So, wait until your milk is regulated, and your baby is growing well.

I also don’t recommend moms start fasting if their baby is less than 6 months old.  At the very least I would wait until your baby is at least 3 months old, you have a healthy and ample milk supply, your baby is gaining weight well, and all things look positive breastfeeding-wise.

Below are a few of my favorite tips based on my personal experience and research to be successful with intermittent fasting while breastfeeding.

Drink More Liquids

Fasting can leave you dehydrated, especially if you are fasting in the summer season. Symptoms that show that your body is dehydrated may include feeling dizzy, dark yellow color of urine, dry mouth and lips, and feeling lethargic or tired.

To avoid these issues, drink as much water and other healthy liquids as you can. Drinks with sugar, like fruit juices, sodas, sweet tea, and coffee with sugar should not be consumed during your fasting window. Instead, drink at least half your body weight in ounces of filtered water, sparkling water (no sugar or sweeteners), and unsweet tea or coffee.

Staying hydrated will keep the water in the blood at a normal level. If you feel dizzy due to dehydration while fasting, then it is recommended to break your fast immediately with a healthy meal and drink water to fulfill your body’s needs.

Eat a Healthy Diet

Eating healthy food will not only benefit you but will help your child as well. Since intermittent fasting prohibits you from eating foods during certain periods of time in the day, it is important to have a nutrition diet when you do eat.

This way, you will provide your body (and breast milk) all of the essential nutrients that you and your baby need for healthy growth. You can try tracking your food to keep track of what you are feeding your body. You want the foods you eat to fuel your body, rather than deplete it. Pick lots of healthy fats like avocados, wild salmon, flax seeds, and eat plenty of fruits and vegetables.

Some mothers may also watch their carbohydrate intake while fasting. I don’t recommend this at first, especially as your body learns this new way of eating. You should stick to healthy, complex carbs like sweet potatoes, quinoa, and fresh fruits.

Stay Rested

When moms are intermittent fasting and breastfeeding, they may feel more tired initially. That’s why I don’t recommend fasting when your baby is still a newborn.

It’s important that you stay hydrated and eat well, so you can give your body the energy that it needs. Rest when your body needs to rest. Whether you’re fasting or not, a breastfeeding mom needs more rest either way.

Look For Changes in Your Baby’s Behavior

Your baby, who relies on you for his nutrition needs, cannot talk and tell you how he or she feels about feeding. So, you will have to keep an eye on your child and notice any little change in their behavior and growth milestones.

Ease Into Intermittent Fasting While Breastfeeding

Intermittent fasting while breastfeeding is not an “all or nothing” type of diet or lifestyle approach. Even if you fast a few days a week, or even if you just do a 16:8 fast, your body is still seeing the amazing benefits.

You may find that over time, you are feeling more energized, and you may even lose weight because you’re eating better and your body now has time to process the foods. Try to stick to meals, with small snacks in between your meals if you are hungry.

Sometimes when breastfeeding, we do feel more hungry because our bodies are burning more calories. This is normal, but you can add healthy fats to your meals to help keep you more satisfied between meals.

Should You Start Intermittent Fasting While Breastfeeding?

Intermittent fasting while breastfeeding is generally considered safe for you as well as for your baby. Plus, it can provide amazing short-term and long-term health benefits for you.

Be sure not to fast longer than 24 hours and if your baby is less than 6 months old. If you are diabetic, or have a history of this disease, be sure to consult with your doctor before starting any new health regimen.

Lastly, if you just need a little more guidance on how to go about intermittent fasting while breastfeeding, be sure to check out my resource which includes fasting information too- Keto and Breastfeeding Video Workshop + Quickstart Guide.