The Impacts of Intermittent Fasting on Fertility
Updated: Feb 13
What is intermittent fasting exactly? Intermittent fasting (IF) is consciously skipping meals throughout the day, typically breakfast. It’s an eating pattern that focuses on when to eat compared to most diets that focus on what. There is no specific mould for how your pattern goes but it’s commonly a fast/feast model where the participant fasts for long periods of time (12 hours up to a full day) and then “feasts” after that can range from 6-12 hours. There are two approaches to intermittent fasting that one can take. The first is the 5:2 approach, which is fasting 2 days a week and consuming meals normally the other 5. Though the majority of those who follow an intermittent fasting approach eat only in an 8-hour window, i.e. 11 a.m. to 7 p.m. and fast the remainder of the time.
Why intermittent fasting? There are scientifically researched medical benefits from IF which includes reducing insulin resistance (decreased risk of Type 2 diabetes), weight loss, better cognition and memory, and reducing the risk of cancer (studies have only been done on animals).
It’s important to note that most of the research has been done on men or animals. Little research has looked at the impacts of fasting and reproduction. Women are more sensitive to signals of starvation and breaking a fast may result in insatiable hunger. A woman’s body wants to protect a potential fetus, even when we are not pregnant. Some women have experienced irregular cravings leading to binge eating, lost menstrual periods, and a decrease in energy. With all types of diet and lifestyle changes, the response will be different.
Considering its impacts on women highlights some of the cycles that regularly occur in a woman’s body. The ovulation cycle and the hypothalamic-pituitary-gonadal (HPG) cycle, which involves 3 hormonal glands. Within the HPG cycle, estrogen and progesterone are produced, which are hormones needed to support pregnancy. Both of these cycles are dependent on energy intake and can be altered by the environment. They are also time-sensitive being that they are cycles. IF can alter these cycles because of the significant change in energy intake throughout long periods of time. It’s important to note that any type of caloric restriction can affect a women’s hormonal health. Knowing this, women who are interested in IF need to be careful that they don’t severely imbalance their hormones.
TIPS ON DOING IT RIGHT: IT’S NOT A BLACK AND WHITE SITUATION
A woman’s hormonal health is like a seesaw and each woman is different. While one thing might cause one woman to go off balance, this same thing can have no effect on another. This type of sensitivity is fine-tuned to each woman, this is why the conversation on how to properly IF as women is a tricky one because this topic has so many variables. If you’re still interested in trying IF, here are a few tips to get started:
DON’T FAST IF YOU HAVE BLOOD SUGAR ISSUES. Hypoglycemia (low blood sugar) is no joke. We don’t want you fainting while trying IF!
BE AWARE OF YOUR SYMPTOMS! Fatigue, bloating, lack of energy, absent menstrual cycles, and headaches to list a few can all suggest an imbalance in hormones which can lead to more severe conditions. I recommend you stop fasting if you experience these symptoms.
DO A TRIAL FAST. The first fast you do should be experimental and allow you some time to observe your body’s reaction. Try a 12-24 hour fast with plenty of water intake throughout.
BE PATIENT. If the trial fast worked out well for you, don’t just jump into an intense IF regimen. Gradually work at your fasting pattern to find the best approach. “Crescendo Fasting” is recommended because it involves fasting only a few days a week on nonconsecutive days. It is important to only perform light yoga/cardio on fasting days as well as consuming proper fluid intake. This is a gentler approach to IF and can be sustained longer.
GO BULLETPROOF. Have you heard of Bulletproof Coffee? It’s the idea of blending grass-fed butter and MCT oil in your morning cup of coffee. That’s right I said butter! Using Bulletproof intermittent fasting principles, you can get the perks of fasting without the risks. By consuming a cup of Bulletproof coffee during your morning fast you are providing your body with energy and fat that are needed to produce sex hormones that are vital to optimal fertility. This is the approach I personally take.
Remember that IF is fairly new into the medical world; long-term research is not available. You can only mostly come across research on rats. Pregnant women should not participate in IF. Consult a medical professional if necessary.
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