Should Moms Do Intermittent Fasting?

80% of women in the US are overweight or obese. Not only that, but the obesity rates have tripled in the last 60 years. It’s no surprise that many women are turning to intermittent fasting as a weight loss approach. Intermittent fasting is one of the most popular diet trends today. However, unlike many fad diets, there is some truth to the hype around intermittent fasting. Some people who do it see significant health benefits.

As effective as it may be, it can be difficult for moms to decide if it’s right for them. Women have different biological needs than men, and fasting can have detrimental effects on a woman’s overall health.

So what’s the verdict? Should moms try intermittent fasting or not? That’s exactly what we’ll cover in this post. The truth, as always, lies somewhere in the middle. Most of us want a simple yes or no answer, but after reading this post, you’ll realize that fasting can be a net positive or negative for you depending on your unique circumstances.

Let’s dive right in!

A Quick Review Of Intermittent Fasting

There are hundreds of articles on the internet that explain what intermittent fasting is and its benefits. At a high level, intermittent fasting involves restricting the period of time during which you can eat (known as the “eating window“) and refraining from eating during other times (known as the “fasting window“).

There are several different ways to approach intermittent fasting:

1) Time-restricted eating

This method involves a fasting window and an eating window each day. Common windows include:

• 16:8 = Fast for 16 hours, Eat for 8 hours
• 18:6 = Fast for 18 hours, Eat for 6 hours
• 20:4 = Fast for 20 hours, Eat for 4 hours

Time-restricted eating is the easiest method to follow because a significant portion of the fasting window is during sleep. For example, on a 16:8 schedule, you might fast from 6pm in the evening until 10am the next day. Then, from 10am to 6pm, you eat all your meals. So out of the 16 hours of fasting, 8 hours are spent sleeping.

2) 5/2 method

This method involves eating normally for five days and then fasting for two days. During the two days of fasting, you eat less than 25% of your daily calorie intake. For example, if you eat 2000 calories per day, then you can only eat up to 500 calories on the 2 fasting days.

This is a more intense form of fasting, and your body essentially enters starvation mode during the two fasting days.

3) Alternate-day fasting

This method involves alternating between fasting and normal eating days. On fasting days, you consume 25% of your daily caloric needs. On eating days, you eat as you normally would without restrictions. This type of fasting is very intense, as your body enters starvation mode every other day.

While there are other variations of intermittent fasting, these are the main methods to be aware of.

What Is The Purpose Of Fasting?

In some cultures, people fast for religious reasons (such as Muslims during Ramadan or Hindus during certain religious holidays). However, many individuals choose to fast voluntarily due to the health benefits it offers. There are numerous articles that explain the advantages of intermittent fasting, so I won’t go into detail here. If you’re looking for a good summary, I recommend reading this.

At its core, intermittent fasting causes three changes in the body, which in turn have a range of downstream benefits:

• Insulin Regulation: During fasting periods, insulin levels decrease, which may lead to improved insulin sensitivity over time. This can help with better blood sugar levels, weight management, and prevent various diseases (such as heart disease and kidney disease).
• Cellular Autophagy: Fasting stimulates a process called autophagy, where the body removes damaged cells and generates new, healthy ones. This process is believed to play a role in longevity and disease prevention.
• Fat Utilization: When fasting, the body starts using stored fat as an energy source. This can help with fat loss and body composition.

Therefore, intermittent fasting has some significant health benefits.

The Risks Of Intermittent Fasting For Moms

Although there are health benefits to intermittent fasting, it also comes with risks, particularly for women. Intermittent fasting (IF) is not a free-for-all. When you do IF, you restrict your calorie intake for a certain period of time. As a result, most people end up eating less because they have less time for food intake. Additionally, their body’s metabolism and hunger cues adjust for the lack of food coming in for extended periods of time, and so they begin to feel less hungry. Both of these factors combined can lead to consuming fewer essential nutrients overall.

Reducing caloric intake is a hormetic stressor on the body. This means that in the right dose, the stress triggers an adaptive response that makes the body stronger and healthier.

While stress is necessary to make the body stronger and healthier, chronic stress does the opposite. Moreover, everyone’s body has a different tolerance for stress. Perhaps the most important factor in determining how much stress a body can tolerate is biological sex.

A female’s physiology is centered around reproduction. Reproduction can only happen if there is an abundance of energy to carry out the processes of ovulation, implantation, and growing a fetus to term. This is a very energy-intensive process and the body needs a constant input of nutrients to be able to carry it out.

Fasting does the opposite of that. When a person fasts, they purposely do not give the body enough calories, which then forces the body to enter survival mode. For men, this can lead to a lot of positive physiological changes. However, women seem to react very differently if their body is chronically forced into a fasted state. The body assumes there aren’t enough resources to reproduce and begins to shut down reproductive processes.

Now, let’s take a closer look at the various ways that fasting can negatively affect mothers or mothers-to-be:

1) Hormone imbalance

When you consume fewer calories, your thyroid gland releases fewer thyroid hormones. This has been proven by studies. For instance, an older study demonstrated that fasting reduces thyroid stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4). Similarly, a study on Muslim women who fast during Ramadan showed a significant decrease in T4 levels after fasting.

Therefore, women with thyroid issues are likely to worsen their condition by fasting.

In addition to thyroid hormones, studies have shown that DHEA levels significantly decrease in women who practice intermittent fasting. DHEA is a necessary hormone that helps produce other hormones like testosterone and estrogen. Unless a woman has high DHEA levels, reducing DHEA levels is not a good idea.

2) Missed period

It is a well-known fact that calorie restriction, which is what happens during fasting, can have a negative impact on a woman’s menstrual cycle. For instance, a study conducted on 85 women during Ramadan showed that almost 25% of them had changes in their menstrual cycle due to fasting. Some women experienced much longer cycles (menorrhagia), while others experienced irregularities (oligomenorrhea).

Every woman’s body has a different capacity for stress. For some women, fasting has been proven to increase cortisol, which leads the body to enter into a sympathetic state. If this happens once in a while, that’s fine. But if fasting becomes an everyday thing, over time, this elevated stress can lead to issues like amenorrhea, where a period is completely missing. Regardless of whether a woman wants to have children or not, her period is like a monthly report card. If fasting causes irregularities or missing periods, it is likely causing more harm than good.

3) Ovary size drops and adrenal gland size increases

Research on rats has shown that while male rats can maintain themselves quite well in a fasted state, female rats do not fare as well. They experience a drop in ovary size, an increase in adrenal gland size (which usually happens when rats are exposed to high stress), and their menstrual cycles become irregular.

As a mother, this is the last thing we want. If we want to have more children, we don’t want our ovary size to decrease. Furthermore, if our adrenals are stressed, we won’t have enough energy to take care of our children.

4) Low energy levels and mood swings

Some women may experience negative effects from fasting, such as feeling cold, constipated, having headaches, low energy, bad temper, and lack of concentration, according to a study published in the National Center for Biotechnology Information. As a mother, having these symptoms is the last thing we want. Taking care of children is a demanding role that requires us to have an abundance of energy. If fasting is causing stress and making you crankier, then it may not be worth it.

5) Glucose tolerance of fasting women worsened!

This is interesting. According to this study, glucose tolerance actually worsened for women after fasting, while it remained unchanged for men. This happened to me personally as well. When I practiced intermittent fasting, my fasted glucose levels were elevated and my blood sugar would spike after I ate my first meal of the day, leaving me feeling very tired and lethargic. However, once I started having breakfast within an hour of waking up, my blood sugar and energy levels became much more stable throughout the day.

6) Nervous system dysregulation

The nervous system has two states: Sympathetic and Parasympathetic. They have opposite roles. The sympathetic is activated during “flight-or-fight” situations and during stressful activities (such as intense exercise, fasting, etc.). The parasympathetic is more active during quiet resting periods. The goal of the sympathetic nervous system is to prepare the body for strenuous physical activity, while the goal of the parasympathetic system is to conserve and store energy and regulate basic body functions such as digestion and urination.

Both states are necessary for survival, but we don’t want to overtax the body by being in a sympathetic state for too long. This can lead to various issues, including suppression of the immune system, excessive oxidative stress, increased blood pressure, atherosclerosis, inflammation, diabetes, heart disease, kidney disease, dementia, and more.

A study conducted on women who underwent a 2-day fast showed that their nervous system shifted more into a sympathetic state. If this were to happen repeatedly due to intermittent fasting, and the women had other stressors in their life besides fasting, then they would end up in a sympathetic state for prolonged periods of time, which is not desirable.

7) Increased risk for eating disorder

A study spanning five years was conducted on 496 adolescent girls. The study revealed that fasting is strongly correlated with the onset of binge eating and bulimia nervosa in the future. It is common knowledge that women are more prone to eating disorders than men. I have personally met several women who started intermittent fasting for its “benefits,” but in reality, it was a way for them to justify their disordered eating habits and orthorexia.

8) Poor pregnancy outcomes and milk supply

Mothers should avoid intermittent fasting during pregnancy or in the early stages of breastfeeding. Several studies have shown the negative effects of fasting during pregnancy. For instance, this study demonstrated that fasting affected the brain and organ growth, as well as the weight gain of offspring, when the female rat fasted while pregnant.

Another extensive census-based study of Muslim populations in Uganda (n = 80,000) and Iraq (n = 250,000) demonstrated that exposure to Ramadan fasting during the first month of pregnancy increased the risk of mental or learning disability in offspring by 50% and psychological disability by 63%! Additionally, a large study on Indonesian women indicated that exposure to Ramadan during pregnancy resulted in smaller statures and thinness in adulthood. Lower birth weight is directly linked to impaired cognitive function. For example, research has shown that Muslim children exposed to Ramadan fasting in utero during the first trimester had significantly lower scores in maths, reading, and writing tests (taken in primary schools at the age of 7 years) than Muslim children who were not exposed to Ramadan fasting in utero.

One study conducted on maternal rats indicated that pregnant women who practiced intermittent fasting had restricted fetal development growth due to down-regulation of the placenta transport system.

Another study demonstrated that the incidence of gestational diabetes INCREASED in pregnant mothers who practiced intermittent fasting.

As you can see, being in a fasted state during pregnancy is NOT recommended.

Breastfeeding and intermittent fasting can be a tricky combination. Most experts agree that it’s not a good idea to do intermittent fasting during the first 6-8 weeks when a mother’s milk production is still being established. This is because a breastfeeding mother needs extra calories to produce enough milk. Fasting can prevent a mom from getting the extra calories she needs, which can lead to low breast milk supply and impact the baby’s weight. However, some women have had success with losing weight while breastfeeding by using intermittent fasting after that initial period. If this is something you’re considering, it’s important to be very careful and make sure you’re meeting your nutritional needs to produce enough milk for your baby.

Considering all the downsides of fasting for moms mentioned above, it can be difficult to decide whether or not to fast. In my opinion, most moms do not need to practice intermittent fasting unless they fall into one of the categories below.

Which Moms Should Do Intermittent Fasting?

There are only a few moms who could safely try intermittent fasting based on their current health profile. Let’s take a look at who this includes:

1) Moms with PCOS

Studies on moms with PCOS who try intermittent fasting show improvements in certain health markers. For example, this study showed improvements in all of the markers below:

• Body mass index (BMI)
• Waist-to-Hip Ratio
• Skeletal muscle mass
• Body fat mass (BFM)
• Body fat percentage (BF%)
• Visceral fat area (VFA)
• Luteinizing hormone (LH)
• Follicle-stimulating hormone (FSH)
• LH/FSH
• Total testosterone (TT)
• Sex hormone-binding globulin (SHBG)
• Free androgen index (FAI)
• Fasting glucose
• Fasting insulin (FINS)
• Homeostasis model assessment-insulin resistance (HOMA-IR)
• Area under the curve (AUC) for insulin (AUCIns)
• Area under the curve (AUC) for glucose (AUCGlu)
• AUCIns/AUCGlu Ratio
• Lipids
• Uric acid
• Alanine aminotransferase (ALT)
• Aspartate aminotransferase
• High-sensitivity C-reactive protein (hsCRP)
• Insulin-like growth factor (IGF-1)

Furthermore, 73% of the women observed significant improvements in their menstrual cycle. These are noteworthy changes. Therefore, mothers with PCOS could reap the benefits of intermittent fasting.

2) Moms who are overweight or obese

Several studies, such as those found here, here, and here, indicate that overweight or obese women can use intermittent fasting as an effective weight loss tool. Therefore, having significant amounts of fat to lose may be a good reason to fast.

3) Moms who are post-menopausal women

I personally know several women who have gone through menopause and swear by intermittent fasting. It makes sense intuitively because at that age, the body no longer prioritizes reproduction, so fasting may be safe for that age group. Therefore, post-menopausal mothers who want to lose weight may find success in using intermittent fasting, especially if they want to improve their body composition.

Mothers who fall into the above three categories could benefit from intermittent fasting. However, it is crucial that you work with a knowledgeable healthcare provider who can help you approach intermittent fasting in a way that allows you to reap the most benefits without experiencing potential risks.

Conclusion

As I mentioned earlier, whether or not a mother should do intermittent fasting really depends on the individual. Some valid reasons to consider intermittent fasting are:

• If you are obese and want to lose body fat
• If you have PCOS
• If you are post-menopausal and want to optimize your body composition

However, for mothers who are of normal weight, the risks associated with intermittent fasting outweigh the potential benefits and are not worth it.

Moreover, there are other ways to achieve benefits such as blood sugar control, autophagy, and fat loss, besides intermittent fasting. Exercise is one such way! That’s correct. In addition to these benefits, exercise also has other advantages such as improved bone and joint health, increased muscle mass, better sleep, a more youthful appearance and feeling, better posture, reduced stress, increased energy, and much more!

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