Home » Nutrition » Intermittent Fasting While Pregnant: Is It Really Safe?

Intermittent Fasting While Pregnant: Is It Really Safe?


The techniques and patterns have evolved with the changing times. The diet plans and styles have been changed and some of them revived.

Exercises and workouts are great to begin with, but the bigger picture is changing your eating habits and patterns.

One of these techniques is the ancient and modern blend, intermittent fasting. It has been largely practiced for a healthy lifestyle and weight loss.

However, women have different phases in life, and becoming a mother is one of the most beautiful changes.

Keeping the changing needs in mind, the question of whether intermittent fasting is safe for moms has recently evolved.

Through this article, we will try to get all the needed information for the “baby-mommas”.

Intermittent Fasting: Basic Idea

Though enough information about intermittent fasting is available, you should know the basics of it.

In case you are a newbie, here’s what you need to know[1].

Intermittent fasting is not a diet plan or food chart, rather it is a pattern of dieting. While following intermittent fasting, you have an eating window and you do not eat for major part of the day.

The eating window doesn’t offer unhealthy options as one has to watch closely what’s being consumed.

Burgers, pizzas, and other unhealthy stuff have to be avoided. The methods that are covered under intermittent fasting are

  1. 16:8 Method

    The 16:8 is the most common approach and is widely practiced. The ratio here is the number of hours a person fasts to the hours a person can consume food.

    This means that the person has to fast for 16 hours of the day and can consume food during the rest 8 hours.

    The period in which you can consume food is called the eating window. However, the eating window has to be used wisely to consume nutritious food that are equally distributed and balanced.

    High-calorie foods have to be consumed in low amounts and calories are to be monitored.

    In the fasting period, black coffee with no sugar is allowed,  it has to be limited. Water is an all-time exception.


  2. 5:2 Method

    5:2 method means you restrict the calorie-rich food for 2 days and eat normally for the rest 5 days of the week.

    This helps provide a build-up for people having difficulty adapting their bodies to prolonged fasting.


  3. Alternate Day Fasting

    Alternate day fasting deals with a complete fast on alternate days.

    This means fasting on non-consecutive days with a day in between for a break and consuming food.

    Regardless of the method, you keep eating only healthy food.


  4. Eat-Stop-Eat

    Eat-stop-eat is just a twisted approach where you keep 24 hours fast twice a week. The two days can be chosen as per priority.

Note: It is not a limited-time program for availing of the needed benefits, it is something to be followed for a lifetime.

How Does Intermittent Fasting Work?

Since you are cutting down the calories, the body uses the stored fat to provide energy for the tasks.

This helps in using up the accumulated fat and you lose some weight and get into better shape with a healthier lifestyle.

According to several studies[2], it is also said that it can improve the quality of life and life expectancy.

This brings us to the main point which is our next question.

Is Intermittent Fasting A Safe Call For Moms To Be?

The safety and side effects of intermittent fasting while pregnant are a tricky topic as there is no rule or full-proof study to answer this. However, since we learned about the basics, methods, and how it works for the body, the simple answer for being on the safer side is No.

The mother needs proper nutrition to keep going with the changes in her body and for her baby’s growth. Fasting for prolonged hours can cause a deficiency in her body and the child.

It can also lead to weakness during this very crucial phase. In addition, sudden changes in the body can affect the later stages of pregnancy and the child.

Studies[3] say that the cravings a pregnant woman experience is due to deficiencies in the body and keeping a prolonged fast may not be a good idea.

Is It Impossible To Follow Intermittent Fasting During Pregnancy?

This is very common for people to ask since they have heard it from someone that it is possible  to practice IF and not affect the baby.

Rather, it is said that IF is healthy for metabolism and energy. The simple explanation for this is every female body is different and experiences different changes.

What works for one doesn’t work for other. It may or may not work for you. If you are already practicing it and it is working well, provided you have enough nutritious[4] food for you and the baby, you can keep going.

But, it is always better to look for the signals your body gives you. You should also consider asking your doctor as every little step can affect  the baby and your health a lot.

How To Decide Whether You Should Go For Intermittent Fasting Or Not?

This is not such a tough call. It can be decided in four steps and you can conclude.

  1. Avoid New Experiments

    Your body is already going through enough changes to introduce another shocker. So it is better to avoid such experiments.

    If you have never tried intermittent fasting before and your increasing weight is bothering you, do not opt for intermittent fasting temporarily because of insecurity.

    It is also commonly observed that women prefer only belly pregnancy and do not want to look fat.

    But the fact is 10-12 kg is a healthy amount of weight for proper growth and development of the new life budding inside you.

    If you were underweight before conceiving, you can gain more weight than this and it is absolutely fine.

    Do not get harsh on yourself for fitting any perfect body standards.

  2. Listen To Your Body

    It is not a smart move to ignore the indicators your body is giving you. It is possible that you were going well with intermittent fasting but after conceiving it is getting hard to continue.

    Your insulin levels may be lowered causing weakness, lightheadedness and even fainting. Your baby might not even make a healthy amount of movements when devoid of nutrition.

    Your body can signal you with cravings. Sometimes, due to nausea, you can’t eat enough during pregnancy and rely on small multiple meals rather than big ones.

    If this is the case with you, do not go for such long fasts. If you are doing well, it can be a good sign, but avoid 16 hours long fasting. Try a shorter one instead.

  3. Ask Your Doctor

    They know the best about your body’s needs and nutrition. If you are lucky enough to experience no problem practicing intermittent fasting, you should still consider asking the doctor as they know best about long-term effects that you might overlook.

  4. Look For A Better Alternative

    If you think the amount of your weight gain is not right and it’s more than necessary, try going for healthier choices like some regular but light workout.

    This will help your body to stay active while cutting down the extra weight. You can also replace it with some safe yoga[5] poses that are recommended during this phase.

    Fasting for a limited number of hours can be okay but not a prolonged one. Stay away[6] from keto diet. It is not a safe alternative as it affects the organ development and embryo a lot.

    If you feel like controlling your diet, eat healthy food with a good amount of calories especially during the last months, as it is crucial to consume more calories in that period.

    If you want to limit food, just control your midnight cravings. Try eating during the day only.


Pregnancy is a beautiful and challenging journey. Do not be harsh on yourself. If you are putting on a healthy amount of weight, you do not need to cut it down.

Calories are an important need for the development of the fetus. Both intermittent fasting and the keto diet are not considered safe during this important phase and hence they should be avoided.

Even if you put on more weight than required, look for alternatives that are far from starving your body. Consider safer exercises and yoga[7] poses for you and the baby.

Consider healthy food options. If you cannot consume big meals, try smaller ones. Avoid any types of fasts and take care of your diet and nutrition.

It should be balanced and evenly distributed. The most you can do in the form of fasting is avoiding  meals during the night.

Even if you follow  the opinion of professionals, they do not recommend intermittent fasting. And that’s all the information you were seeking about IF during pregnancy.

7 Sources/References

  1. Research on intermittent fasting shows health benefits. February 27, 2020; Available from: https://www.nia.nih.gov/news/research-intermittent-fasting-shows-health-benefits.
  2. Mary-Catherine Stockman, RD, LDN,1 Dylan Thomas, MD,1 Jacquelyn Burke, MS, RD,2 and Caroline M. Apovian, MD1. Intermittent Fasting: Is the Wait Worth the Weight? Curr Obes Rep. 2018 Jun; 7(2): 172–185.
    doi: 10.1007/s13679-018-0308-9
  3. Jocelyn D Glazier, Dexter J L Hayes, Sabiha Hussain et. al. The effect of Ramadan fasting during pregnancy on perinatal outcomes: a systematic review and meta-analysis. BMC Pregnancy Childbirth. 2018 Oct 25;18(1):421. doi: 10.1186/s12884-018-2048-y.
  4. Michelle A. Kominiarek, MD, MS, Associate Professor. Nutrition Recommendations in Pregnancy and Lactation. Med Clin North Am. 2016 Nov; 100(6): 1199–1215. doi: 10.1016/j.mcna.2016.06.004
  5. Sally K. Hinman, MD, PhD,*† Kristy B. Smith, MD,† David M. Quillen, MD,† and M. Seth Smith, MD, PharmD‡. Exercise in Pregnancy. Sports Health. 2015 Nov; 7(6): 527–531. DOI: 10.1177/1941738115599358
  6. Dafna Sussman,corresponding author1,2 Matthijs van Eede,2 Michael D Wong,1,2 Susan Lee Adamson,3,4 and Mark Henkelman1,2. Effects of a ketogenic diet during pregnancy on embryonic growth in the mouse. BMC Pregnancy Childbirth. 2013; 13: 109. Published online 2013 May 8. doi: 10.1186/1471-2393-13-109
  7. Kathryn Curtis,* Aliza Weinrib, and Joel Katz. Systematic Review of Yoga for Pregnant Women: Current Status and Future Directions. Evid Based Complement Alternat Med. 2012; 2012: 715942. Published online 2012 Aug 14. doi: 10.1155/2012/715942

Leave a Comment

Working For Health

Working4health provides health news and health information which is backed by science.


Working For Health

#7293, 66 W Flagler Street STE 900 , Miami, FL 33130, United States