intermittent fasting for women

Intermittent Fasting for Women: A Definitive Guide

For a long time, I thought intermittent fasting meant skipping breakfast every day. I “tried,” and didn’t like it, so I decided that it was not for me. Moreover, I read that intermittent fasting can have adverse effects on women’s hormonal health. I figured women should avoid it as a general rule. However, I recently learned how women can reap all the benefits of fasting without throwing off their hormones. Let me share what I discovered with you.

Types of Intermittent Fasting

There are many different ways to do intermittent fasting. That’s what makes it so great. When I was convinced that intermittent fasting could be harmful to me as a woman, I was thinking about daily intermittent fasting. I didn’t realize that there are many different types of intermittent fasting:

  • 16/8 Daily fasting: Probably the most common and well-known type of fasting. You fast for 16 hours and eat your meals within 8 hours.
  • 20/4 Daily fasting: In this case, you cut your eating window in half. There are many other different variations of daily fasting, and some people even eat all their food within an hour timeframe. However, 16/8 and 20/4 are the two daily fasting choices most often referred to.
  • 5:2 Diet: Eat normally for days while restricting your calorie intake to 500-600 calories the remaining two days.
  • Eat-Stop-Eat: This type of intermittent fasting requires you to fast for 24 hours each week. You could start after dinner one day and eat dinner the next evening after your 24 hours are up.

The Fasting Mimicking Diet

When I first heard of the fasting mimicking diet, I thought it was a type of intermittent fasting. Not quite! The purpose is slight starvation for an extended period (4-5 days). Prolonged fasts have been shown to allow for greater benefits as far as cell regeneration goes. However, prolonged water fasting can have negative effects, and that’s where the fasting mimicking diet comes in.

Differences Between the Fasting Mimicking Diet and Intermittent Fasting

Before we talk about how women can benefit from intermittent fasting, I want to explain the difference between fasting mimicking and intermittent fasting. Understanding the difference will matter when you, as a woman, decide what type of fasting you would like to practice.

  1. The fasting mimicking diet (FMD) does not only define your eating-fasting cycle. It also specifies the types of foods and the macronutrient ratios you need to be consuming. My post The Fasting Mimicking Diet: Benefit From Fasting Without Giving Up Food explains it all.
  2. The FMD is a prolonged fast. Intermittent fasting is always for less than 48 hours.

Why Intermittent Fasting Works

A significant advantage of intermittent fasting is that you accommodate it to suit your lifestyle and your needs. You can even eat the foods you want to eat, contrary to many “diets” out there that require you to follow a specific plan.

Intermittent Fasting Benefits

Intermittent fasting, like fasting mimicking, reproduces many of the benefits of fasting without having to undergo a water fast.

Special Considerations for Women

  • Women, because of the significance of their reproductive abilities, have a high sensitivity to starvation. When they go without food, starvation signals are sent to the brain, and their body will ramp up the production of hunger hormones (leptin and ghrelin).
  • When the production of leptin and ghrelin increases, it can cause hormonal imbalances.
  • Women who are pregnant or breastfeeding should avoid long term sustained intermittent fasting.
  • Underweight women should avoid intermittent fasting.
  • Women who have a history of fertility problems should avoid fasting as well.

Intermittent Fasting and Women’s Hormonal Health

Adrenal Function

Cortisol is your body’s main stress hormone and is released by your adrenal glands. If your cortisol levels are always high or always low, it means your brain is not communicating properly with your adrenals.

Here are some symptoms you might experience:

  • Trouble getting started in the morning
  • Craving salty or sugary foods
  • Low sex drive
  • Fatigued in the afternoon but you get a “second wind” in the evening
  • Trouble staying asleep at night
  • Dizziness after standing up too quickly
  • Afternoon headaches
  • Blood sugar issues
  • Chronic inflammation
  • Weak nails and brittle hair
  • Moodiness
  • Trouble losing weight

For some women, the stress of fasting is too much for the adrenals, so they feel worse than before. Women with adrenal dysfunction should be careful when experimenting with intermittent fasting. Crescendo fasting with a longer eating window (around 14-16 hours) would be a good place to start (see below for your crescendo intermittent fasting meal plan).

Thyroid Function

Your thyroid affects every cell in your body because every cell in your body needs thyroid hormone to produce energy. Many thyroid problems won’t show in standard lab work because they stem not from the lack of thyroid hormone but from the ineffectiveness of the body to convert thyroid hormone.

Thyroid dysfunction may cause the following symptoms:

  • Feeling tired
  • Cold feet, hands, or cold all over
  • Requiring extra sleep to function properly
  • Rapid weight gain
  • Constipation
  • Depressed or lack of motivation
  • Morning headaches that subside as the day goes on
  • Thinning of the outer third of eyebrows
  • Excessive hair loss or thinning
  • Dry skin
  • Brain fog

The stress of fasting impacts your metabolism and the way your body uses energy. It increases cortisol levels and causes a drop in thyroid hormone T3. Since intermittent fasting helps reduce inflammation, it improves diseases like multiple sclerosis and rheumatoid arthritis. It may help improve other autoimmune conditions, but more research is needed. Once again, the key is to start slowly and monitor your body’s reaction. Make sure you are not eating inflammatory foods when you are not fasting.

How To Practice Intermittent Fasting Safely for Women

As a general rule, women should phase their intermittent fasting practices for best results. Whatever method you chose as a woman, you need to make sure you are not practicing it on a sustained long term basis. This way, you get to reap the benefits of intermittent fasting while giving your body a chance to resume its normal function regularly. Many recommend women start the crescendo intermittent fasting method.

What is the Crescendo Method?

The crescendo method means you are not fasting every day of the week. For example, you could fast for 16 hours, three nonconsecutive days a week (like Monday, Wednesday, and Friday).

Crescendo Intermittent Fasting 7-Day Meal Plan

intermittent fasting for women - crescendo fasting meal plan

Other Ways To Get the Most Fasting Benefits for Women

As I mentioned before, many fasting benefits increase as you increase the duration of the fast. For example, it takes 18 hours before the body starts to switch to burning fat rather than glucose. Many cell regeneration benefits begin after a 3-day fast. For example, fasting for up to 5 days may protect patients from the effects of chemotherapy. If you want to get the most fasting benefits without impacting your hormonal function negatively, there are a few more options available to you:

  • Fasting mimicking: My favorite method even though it’s not quite the same as intermittent fasting, as I said. The reason I prefer it is that it allows you to extend the duration of your fast safely for maximum benefits. If you are a woman over 40, you will enjoy this post about Fasting for Women Over 40.
  • Eat-Stop-Eat (or the 24-hour protocol): You can start with a 16-hour fast and build gradually. The idea is to fast 2-3 times a week.
  • 5:2 Diet: Restrict your calories to 20-25% of your regular intake two consecutive days a week. The fasting mimicking diet allows you to consume up to 40% of your regular intake for a more extended period.
  • Modified alternate-day fasting: If you use this method, you fast every other day but are allowed to consume 20-25% of your normal caloric intake on fasting days.

Individual Differences Among Women

Body shape and composition are a predictor of different biochemical markers among women. The point being: Intermittent fasting will impact different women differently. Each person is unique, and this fact doesn’t stop at gender differences. You are the owner of your body. For this reason, you need to experiment to see what works for you.

Warning Signs You Should Stop Intermittent Fasting

If you notice any of the following signs, I recommend you take a step back:

  • Hair loss
  • Low energy
  • Mood swings
  • Muscle pain
  • Low libido
  • Changes in your menstrual cycles

In Summary

The beauty of intermittent fasting is that you get to choose and experiment with how long you fast. You can make it work for YOU. If like me, you thought intermittent fasting wasn’t a good idea for women, I hope I showed you that it isn’t true. Intermittent fasting can be adapted in so many ways; it can work for women.

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intermittent fasting for women