Pros and Cons of Intermittent Fasting With PCOS

Updated December 2021

by Amy Medling, founder of PCOS Diva

Intermittent fasting (IF) is a hot topic in the diet and nutrition world right now.  Many experts tout the benefits of fasting for a portion of the day, including increased longevity and a reduction in common diseases.  Others warn against disrupting sugar and hormone rhythms and eating disorders.  Is it the right treatment for women with Polycystic Ovarian Syndrome (PCOS)?  As always, that depends upon the woman.

Intermittent fasting is nothing new.  Breakfast lunch and dinner are western conventions that have only been around for a few centuries.  Before that, our ancestors ate when they were hungry, or, more likely, when there was food available.  That often meant long intervals between meals.  Today, intermittent fasting is considered a break in eating for many hours at a time or an extreme reduction in the amount you eat for a couple of days per week.  For example, you may finish dinner at 6:30 pm and not eat again until breakfast at 9:30 am.  Alternatively, you may eat very lightly on Tuesday and Friday and normally the rest of the week.

Research indicates 5 ways that intermittent fasting may benefit women with PCOS.

Please read #2 carefully.

1) Cellular and Hormone Regeneration

Studies show that when you practice intermittent fasting, important things happen to your cells and hormones:

• Your body’s cells begin a repair and waste removal process.
• Blood levels of human growth hormone (HGH) increase, which aids in fat burning and muscle gain.  It also helps to regulate body fluids, bone growth, sugar and fat metabolism, and possibly heart function.  Basically, HGH makes us fit and feel better.

2) Lower Insulin

When you fast, blood levels of insulin drop dramatically, initiating fat burning. It may also lower your risk of type II diabetes since a recent study shows that fasting blood sugar has been reduced by 3-6% while fasting insulin has been reduced by 20-31%. Before you get too excited, you should know that this data may not be reflective of both genders.  A recent study on women showed that blood sugar control actually worsened after a 22-day long intermittent fasting regimen.

3) Weight Loss

Limiting the time frame in which you can eat will likely reduce the number of calories that you take in. Coupled with the decrease in insulin levels and the increase in human growth hormone, that can lead to weight loss by boosting your metabolism.  Less calories + faster metabolism = weight loss.

4) Fight Inflammation and Oxidative Stress

Oxidative stress is an imbalance between the production of free radicals and the ability of the body to detoxify their harmful effects. This stress has been linked in studies to aging and many chronic diseases.  IF works to eliminate this stress. In addition, intermittent fasting may reduce inflammation (a common core symptom in women with PCOS).

5) Brain Health & Depression

Intermittent fasting may enhance many metabolic functions that impact your brain health. We have already discussed reduced oxidative stress, inflammation, blood sugar levels and insulin resistance which all impact brain function, but studies show that IF may even increase the growth of new nerve cells.  Finally, IF increases levels of brain-derived neurotrophic factor (BDNF).  Deficiency in BDNF is linked to depression (another common symptom of PCOS).

There are many, many additional benefits to intermittent fasting, and it seems that new research studies tout its benefits every day. There are some concerns, however.  For example, a 2011 Brazilian study on long-term IF found that it actually increased blood glucose levels and increased oxidizing compounds.  Other experts raise concerns about development of binge eating habits or exacerbation of other eating disorders.

So is intermittent fasting with PCOS a good idea for women?

Maybe.  There are some people who should not try intermittent fasting at all (people with an eating disorder, for example).  You probably shouldn’t fast if you are required to be “on your game” every moment of the day.  Hunger pangs can be distracting to an extreme. Also, if you have an impaired metabolism or have diabetes, skipping meals can wreak havoc on an already precarious balance.

Others should try it with caution.  Keep in mind that women are extremely sensitive to starvation signals.  Our hunger hormones kick in and demand that we eat (even gorge) in order to protect a hypothetical fetus. This cycle of binging and fasting can actually stop ovulation. If you fast for a while and find that this is your pattern, intermittent fasting is not for you.

How do you do it?

There are many theories on how to make the most of fasting.  Here might be a good way to start:

• In my February interview with Dr. Dian Ginsberg, MD, we discussed intermittent fasting for women with PCOS. She suggested a 12 hour fast, four nights a week from 6:00 PM to 6:00 AM when you don’t eat. That, she says, creates a stress. “If you’re eating a whole food diet and you’re not loaded with all the sugar, that’s where your body will start to burn your fat while you’re sleeping. Weight will go down, insulin will stabilize, growth hormone actually goes up as you burn fat, and growth hormone makes us fit and feel better.”

I always tell my clients, “We are all bio individuals.”  What works for one person does not work for the next.  If you feel like this is something you would like to try, I encourage you to give intermittent fasting a shot and see if it works for you.

Next Steps:

Are you ready to start managing your PCOS, but are overwhelmed and don’t know what to eat? Or perhaps you are super busy and don’t have time to plan your meals each week (most of my clients have this problem!). You are in luck. PCOS Meal Plans can help!

Amy Medling, the best-selling author of Healing PCOS and certified health coach, specializes in working with women with Polycystic Ovary Syndrome (PCOS), who are frustrated and have lost all hope when the only solution their doctors offer is to lose weight, take a pill, and live with their symptoms. In response, Amy founded PCOS Diva and developed a proven protocol of supplements, diet, and lifestyle programs that offer women tools to help gain control of their PCOS and regain their fertility, femininity, health, and happiness.  

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