Keto For PCOS: Should You Follow It?

I think you will agree with me when I say, the keto diet is one of the most talked about diets in the PCOS community.

Many keto advocates speak of the health benefits they have experienced. This may have you wondering, should I follow it?

In this post, you will find the keto diet is right for you. We will look at what the keto diet is, its benefits and drawbacks for PCOS and ultimately if it is healthy for women with PCOS.

Is the Keto Diet Best for PCOS?

In recent years, the keto diet has gained popularity. It has been shown to improve insulin resistance, boost weight loss and lower levels of inflammation in the body. Because of these huge benefits, the keto diet has become a recommended diet for the treatment of PCOS. But despite these benefits, the keto diet may not be the best for your type of PCOS. Unfortunately, there is no best or standardized diet for PCOS. It is important PCOS women identify their current hormonal state before trying a new diet which may, in the long term, cause more harm than good.

Let’s take a quick look at what the keto diet is before we delve into the benefits and drawbacks for women with PCOS.

What is the Keto Diet?

The Keto Diet (a.k.a the ketogenic diet) was developed in the 1920's as a treatment for epilepsy. It is a high fat, moderate protein and very low carb diet (70% fat, 25% protein and 5% carbs).

The significant reduction in carbs puts your body in ketosis. This is a metabolic process that happens after 3-4 days of eating low carb (less than 50g a day). Because there is no sugar in the blood to be used as energy, the body turns to fat. The body breaks down stored or consumed fats into fatty acids in the liver (a process called beta-oxidation). This process then creates a by-product called ketones (energy molecules) that build up in the blood and are used as energy.

You now know what the keto diet is and how it works, let’s take a look at the benefits for PCOS.

The Benefits of the Keto Diet for PCOS

So, as I mentioned, the keto diet is very popular in the PCOS community. Many women follow it because they believe it will help their PCOS and symptoms.

But here's the thing.

There are only a handful of clinical studies on the keto diet for PCOS. I found one pilot study in which 11 PCOS women followed a low carb ketogenic diet (LCKD) for 24 weeks.

Out of the 11 participants at the beginning of the study, 5 remained until the end. The LCKD  led to a significant reduction in body weight and free testosterone (testosterone that is active in the body). As well as a decrease in luteinizing hormone (LH)/follicle-stimulating hormone (FSH) ratios and fasting insulin. Also, two women became pregnant despite previous infertility problems.

These are huge improvements, but the results were based upon 5 women. The researchers said that more studies are needed to determine if the effects are due to weight loss or the diet. So, we cannot say with certainty that the keto diet is best for PCOS women.

So here’s the deal.

Because of the lack of research, this article will strictly be an evidence-based guide. I will simply be identifying what the science shows.

The Keto Diet Lowers Insulin Resistance

Insulin resistance is the most common root cause of PCOS, with about 70% of women suffering from this.

It is a condition where the cells in the body don't respond to the signal insulin is giving and as a result, blood sugar levels remain high. To reduce blood sugar levels the pancreas starts producing even more insulin. High levels of insulin in the body then has the unwanted side effect of telling the ovaries to produce more androgens. Which then causes the PCOS symptoms women experience.

The keto diet is said to be the most effective way of improving blood sugar levels. A study found a low carbohydrate ketogenic diet led to greater improvements in hemoglobin A1c levels (blood sugar levels over the past three months).

So a keto diet may be an effective way to lower blood sugar levels and as a result, reduce insulin levels. Because if there is no sugar in the blood, insulin is not being produced.

Helps with Weight Loss

Weight gain and difficulty losing weight is a common symptom of PCOS.

A study comparing a low carbohydrate ketogenic diet to a calorie-restricted (LCKD) low-fat diet found the LCKD to be more effective. Participants in the LCKD lost more weight and body fat compared to the low-fat diet group.

The keto diet may help with weight loss because of the increased consumption of fat and protein. This is because both food groups are more filling and satiating. So, as a result, it suppresses our appetite and we eat fewer calories overall.

Lowers Inflammation

Most women with PCOS have high levels of inflammation in the body. Many factors can cause it including insulin resistance.

But, researchers have found the keto diet can lower inflammation.

How you ask?

Well as discussed, when your body switches from burning sugar to fat, you enter into ketosis. Now, the ketones that are used as fuel by the body have anti-inflammatory properties. Pretty incredible right?

So, the keto diet can help reduce levels of inflammation in the body and as a result improve PCOS.


Simply put…

All of the above benefits are incredible. The results show a decrease in insulin resistance, fat loss and inflammation. Such results are highly encouraging for women with PCOS.

But, there are some drawbacks.

Drawbacks of the Keto Diet for PCOS

Below are the risks of the keto diet based on current research and information from experts.

Women with Adrenal PCOS or Hypothyroidism Should Not Follow the Keto Diet

The keto diet may be beneficial for PCOS women who suffer from insulin resistance. However, it may not be suitable for all women with PCOS.

Contrary to popular belief, PCOS is not one condition. It is instead a set of symptoms and there are different types of PCOS. These types are possible root causes of PCOS.

Adrenal PCOS

When we are stressed the fight or flight stress response is activated. This causes the adrenals (an organ found on top of the kidneys) to release cortisol and adrenaline. As well as three male hormones, DHEA, DHEA-S and androstenedione.

As you can see, the ovary is not the only organ that releases male hormones, so do the adrenals. Excess male hormones released by the adrenals is the root cause of about 20-30% of women’s PCOS.

Research shows that cortisol levels are highest when following a very low carbohydrate diet. So following a low carb ketogenic diet may not be such a good idea if you suffer from high cortisol or adrenal PCOS.

Hypothyroidism- A ‘Hidden Cause’ of PCOS

Researchers have found that up to 25% of women with PCOS have a thyroid condition. Unfortunately, problems with the thyroid are often missed in women with PCOS. This is why this type of PCOS is known as a ‘hidden cause’.

Hypothyroidism is a condition where the thyroid is underactive. Meaning it is not producing enough of the thyroid hormones. As a result, key functions like metabolism, ovulation and heart rate begin to slow down.

Dr. Chris Kresser (a functional medicine practitioner) says hypothyroid patients should avoid low carb diets. This because carbs are needed for optimal thyroid function.


Insulin is needed to convert T4 (the inactive thyroid hormone) into T3 (the active thyroid hormone). But because insulin tends to be low on the keto diet, this conversion does not occur. As a result, this can affect thyroid function.

So, the keto diet is not a way of eating that should be recommended as a standardized diet for PCOS.

To find out more about the different types of PCOS and which you may have, check out my Types of PCOS: Ultimate Guide.


The Keto Diet is Low in Fiber

Due to the low carbohydrate intake, many high fiber foods are eliminated from a person’s diet. But fiber is a form of carb all women need to include in their PCOS diet. There are two types of fiber, soluble and insoluble.

Soluble fiber dissolves in water to form a liquid gel. This gel helps slow down digestion. Because of this, nutrient absorption also slows down. Soluble fiber also softens the stool to allow easy movement through the gastrointestinal tract (GI tract).

Insoluble fiber, on the other hand, does not dissolve in water. It instead absorbs water which also allows the stool to remain in solid form and pass easily through the intestines. Because of this, insoluble fiber is often recommended to help with constipation.

The Keto Diet can Impact the Health of Your Gut

Following on from the drawback above, the lack of fiber on the keto diet can alter your gut bacteria.


When we consume healthy amounts of fiber (25-30g per day) we feed and support our gut bacteria so they can thrive. In turn, the number and form of gut bacteria increases.

But when our gut bacteria starve, they feed off the natural layer of mucus that lines the gut. They feed off the mucus to the point where harmful bacteria and viruses can infect the colon wall.


Signs of an unhealthy gut include

  • Bloating
  • Diarrhea
  • Constipation
  • Difficulty losing weight
  • Yeast Infections
  • Anxiety and Depression
  • Lack of Energy
  • Skin Problems


So, it is vital that we nourish our gut bacteria with fiber to ensure our mucus wall remains thick and to protect our body from dangerous bacteria.

Following the Keto Diet can Cause a Loss of Menstrual Cycle

Female sex hormones are sensitive to energy intake. So women must take care when adjusting their food intake to prevent any negative effects.

The hypothalamus secretes gonadotropin-releasing hormone (GnRH). GnRH stimulates the pituitary gland (a region in the brain) to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH).

LH and FSH then trigger the production of the female sex hormones estrogen and progesterone. Women require both hormones during ovulation to release a mature egg. Sudden changes in energy intake, for example, through following a low carb keto diet can throw off GnRH pulses and increase LH levels.

Diet changes stress the body

Altering your food intake in any way, e.g. eating less carbs, creates a negative energy balance which your body perceives as a stressor. Our bodies cannot distinguish between a real imminent threat and you simply trying to lose weight.

Cortisol prevents GnRH from carrying out its role and stops the production of estrogen and progesterone.

During periods of stress, progesterone is converted to cortisol. This then results in less progesterone and even more cortisol. Not enough progesterone leads to estrogen dominance which can cause even more problems.

You might be wondering:

Well, what's the big deal if I miss my period?

Here's the deal:

You might be saying to yourself I am not currently looking to get pregnant so why does it matter if I don't see a period. Sure, females menstruate for the sole purpose of bearing children. But, there are more reasons why you need a menstrual cycle. Including:

  • bone health
  • energy
  • better moods
  • libido

So while everything may seem perfect in the short term, in the long term you will notice huge changes in how you feel.

But also, many women with PCOS already suffer from irregular periods, so the keto diet may not help them in this respect.


The Keto Diet is Not Sustainable

There are other ways you can reap the benefits of keto for PCOS that are sustainable in the long term.

Because let’s be real for a second.

Can you really see yourself never eating carbohydrates again?

Some of the participants in the pilot study, mentioned above in the benefits section, couldn’t adhere to the LCKD because of food preferences.


You Can Still Eat Carbs

Not all carbs are created equally. Meaning not all carbs are ‘bad’ for you.

The problem is not the carbs. You see, over the last 50 years, people have been consuming a lot more refined/processed carbs.

Now, there are two types of carbohydrates, natural and refined.

Natural Carbohydrates

Natural carbohydrates have not been processed and remain in their natural state. They are a source of vitamins and minerals. Natural carbs include plant foods such as sweet potatoes, legumes, vegetables and fruits.

These natural carbs are also known as complex carbs. The body breaks them down slowly because of their high fibre content. Studies show fiber can lower blood sugar levels. It does this by slowing down digestion and the release of sugar. This then prevents huge spikes in blood sugar and insulin.

Refined Carbohydrates

Refined carbohydrates are man-made. They use sweeteners and preservatives to change the way they taste and stop them from going bad. Examples of refined carbs include bread, cereals, pasta, artificial sweeteners.

Overconsumption of these refined/processed carbs is harmful to the body. This is because they contain a synthetic sweetener called High-Fructose Corn Syrup (HFCS).

Now, the amount of carbs you consume depends upon your own tolerance to them and the severity of your insulin resistance. So it is important to work with a medical professional to work this out.

Always combine carbohydrates with a protein and fat. By combining all three food groups, blood sugar levels will not spike causing a surge in insulin.

To learn more ways to treat insulin resistance, check out my ‘Types of PCOS: Ultimate Guide’.

Keto Increases the Risk of Diabetic Ketoacidosis (DKA)

As discussed, following the keto diet increases the amount of ketones in your blood. But this can be dangerous if not monitored.

Too many ketones in the blood may lead to a serious condition called diabetic ketoacidosis (DKA). If the high amounts of ketones in your blood are left unchecked, they can build up and make your blood acidic. This is why the keto diet should be followed under the direct supervision of a medical professional.

Signs of DKA include consistently high blood sugar, nausea, difficulty breathing, dry mouth As well as frequent urination, breath that smells like fruit and feeling more tired.

Should You Follow The Keto Diet For PCOS?

So the question remains, should women with PCOS follow the keto diet? The evidence clearly shows the keto diet has huge benefits including improved insulin resistance, weight loss and reduced levels of inflammation in the body. But, the jury is still out on whether the keto diet is healthy and safe for women with PCOS.

Unfortunately, there isn't a straight forward answer. Firstly because there is not enough research looking at the impact of keto for PCOS. Secondly, there are tons of conflicting results and information among researchers. Studies provide evidence for and against following keto.

Address Your Root Cause

Remember there is more than one type of PCOS and we are all different. So what works for one person doesn't mean it will work for you. Before embarking on any new diet, you must be aware of your current hormonal state to avoid causing further problems to your health. So if you suffer from adrenal PCOS or hypothyroidism the keto diet may not be healthy or safe.

Though there are some huge benefits, there are also serious risks to the keto diet. They include low in fiber intake, may impact the health of your gut and your menstrual cycle. The keto diet is also not sustainable for most and it puts you at risk of diabetic ketoacidosis.

Proceed with Caution

Here is what you must do if you decide to follow keto for PCOS. Pay close attention to how you are feeling. Stop following it if you experience symptoms of an unhealthy gut, loss of menstrual cycle, and signs of diabetic ketoacidosis.

Bottom Line

If you don't suffer from adrenal PCOS, hypothyroidism or have an irregular period, keto may be a safe and healthy approach to follow for your PCOS. But always consult a medical professional before you change your diet. And remember, listen to your body!


Hey there! I am Despina Pavlou, founder of PCOS Oracle, certified personal trainer and corrective exercise specialist.  I want to share with you the diet and lifestyle changes I made to naturally reverse my PCOS and achieve hormonal balance. I believe using my holistic approach you too can take back control from PCOS.

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