The Relationship Between Insulin Resistance and PCOS

8 minutes read

Polycystic ovarian syndrome (PCOS) is a hormonal disorder that affects the menstruation cycles and fertility of women of childbearing age, potentially leading to difficulty conceiving or even early pregnancy loss.

One of the challenges with diagnosing PCOS is that its cause isn’t exactly known, and its many symptoms overlap with those of other conditions and disorders. And unlike the well-defined five diagnostic criteria for metabolic health, experts haven’t yet agreed upon a set of symptoms that indicate a PCOS diagnosis, which is a challenge because it affects between 4% and 20% of women around the world (i.e., up to 780 million people) [1].

Still, researchers are gaining more clarity on the link between PCOS, blood glucose, and insulin resistance — as well as associated symptoms related to weight, mood, and focus. The good news is that it’s possible to manage insulin resistance with PCOS via lifestyle habits, like nutrition and exercise [2].

What are PCOS symptoms and pathophysiology?

The word “polycystic” means multiple abnormal, fluid-filled sacs known as cysts, while “ovarian” refers to the female sex organs where menstruation, hormone production, and egg release occur.

Common symptoms of PCOS include inappropriate hair growth, weight gain, acne, thinning hair, and absence of periods [3].

Besides physical symptoms, PCOS is also associated with emotional distress — one small study of 60 participants found that women with PCOS were significantly more likely to report being depressed, anxious, and stressed compared to women without PCOS [4].

In fact, emerging research indicates that women with PCOS may even have lower levels of certain neurotransmitters (chemical messengers) such as serotonin, which is associated with positive feelings, and as a result are more likely to report depression and anxiety [5].

While the presence of cysts on the ovaries is the defining characteristic of PCOS, there are other accompanying complications, such as [6]:

Infertility
Increased insulin resistance
Increased risk for heart disease and Type 2 diabetes
Elevated cholesterol and triglyceride levels
Increased levels of the male sex hormones, specifically androgen

Experts argue that if co-occurring metabolic complications, like insulin resistance, Type 2 diabetes, and high androgen (male sex hormones, such as testosterone) levels aren’t recognized as part of the diagnosis, PCOS cannot be fully understood or adequately managed.

How does PCOS relate to metabolic health and insulin resistance?

Metabolic health is a common term we hear a lot but what exactly does it mean? Unlike metabolism, which is the sum of all the chemical reactions required to break food down and convert it into energy, metabolic health refers to how well the body uses those foods.

If these chemical reactions are like the many musical instruments in an orchestra that work together to create one harmonious sound, then hormones are the conductor. Hormones direct many of these chemical reactions, such as inducing hunger when we need energy, increasing the feeling of fullness when we no longer need food or signaling tiredness to prepare ourselves for sleep. They help all parts of our body to function as one cohesive unit.

Insulin: the hormone that manages energy

Insulin is a hormone that your pancreas releases when you eat carbohydrates so that your cells can take in glucose (a simple sugar that is the body’s preferred form of energy).

Normally, insulin binds to cell receptors to get glucose absorbed. However, in cases of insulin resistance, cells in the body may not respond to this hormone and therefore be unable to absorb the glucose. As a result, blood glucose levels can spike and remain high over time, leading to irregularities in metabolism and an out-of-sync orchestra.

How PCOS disrupts our hormones

If our conductor is mistiming his cues, the whole orchestra will be chaotic and lack harmony. As a hormonal disorder, PCOS has an impact on the performance of our hormone conductors, including insulin, androgens, and reproductive hormones.

Lack of insulin function can result in high blood glucose. Elevated androgens (which are necessary for fertility at healthy levels) can lead to irregular periods and even insulin resistance [9, 10]. And imbalanced reproductive hormones may impair reproductive capabilities and increase the risk of infertility.

PCOS and insulin resistance

While the relationship between PCOS and insulin resistance isn’t completely clear, research indicates that women who have PCOS are also more likely to experience insulin resistance [6]. It’s estimated that insulin resistance affects 65-75% of women with PCOS and scientists have found that insulin resistance may contribute to the initial development of PCOS [11, 12].

PCOS affects women of all sizes and backgrounds. However, obesity is another metabolic disease that often coexists with PCOS. While it is well known that obesity is strongly associated with increased insulin resistance, research suggests that it may also be a risk factor for PCOS [13, 14]. The interaction between hormones in these metabolic conditions – obesity, insulin resistance, and high levels of androgens – is poorly understood in relation to the development of PCOS, and more research is needed to clarify the role they play in the development and progression of PCOS [15].

How can managing glucose help with PCOS?

As we’ve discussed, insulin resistance contributes to high blood glucose levels. If these levels remain high over time, metabolic health issues become worse. While stable glucose won’t solve everything, maintaining consistent levels throughout the day can improve hormone health, mood, and energy as well as reverse insulin resistance and some of the symptoms associated with PCOS.

Two important ways you can manage your glucose levels (and help your hormone conductors do their jobs) are diet and exercise. One recent meta-analysis suggested that a combination of a healthy diet and regular exercise was just as effective at reducing insulin resistance as medication [16].

Another recent study showed that women with PCOS and obesity who lowered their caloric intake by 600 calories per day and participated in at least 30 minutes of moderate physical activity two to three times per week experienced weight loss and better metabolic profiles at both three and six months from the start of the study [17].

But what are some specific foods and exercises that help with PCOS?

Managing blood glucose with food

While there is no specific diet to cure symptoms of PCOS, there are several nutrition strategies that may help.

Eating whole grain, fiber-rich carbohydrates with protein may reduce insulin resistance, improve hormone imbalances, and decrease levels of androgens and cholesterol, minimizing PCOS symptoms [18, 19].

On top of that, eating plenty of anti-inflammatory foods (such as colorful fruits and vegetables, extra virgin olive oil, and fish) may help manage some of the elevated chronic inflammation that women with PCOS experience [20].

In general, prioritizing whole, unprocessed foods with a low glycemic index — and avoiding refined carbohydrates that can trigger a glucose spike — can also help with weight loss and potentially lessen the effects of both insulin resistance and obesity. While no single diet can meet all your needs, you may find it helpful to take inspiration from the Mediterranean diet and other eating patterns that are rooted in healthy fats, lean protein, and complex carbohydrates — all of which can get your “metabolism orchestra” in tune [21].

Making sure you’re eating enough fiber is also a key part of stabilizing your blood glucose levels. Frequently eating foods that lack fiber can cause blood sugar spikes and may worsen insulin resistance, so minimize your consumption of refined carbohydrates such as white bread, white rice, and anything sweetened with sucrose or high-fructose corn syrup [22].

Managing blood glucose with exercise

Exercise — both aerobic and resistance — can also help manage blood glucose and reverse insulin resistance. In general, research has shown that exercise may help with weight reduction, decreased insulin resistance, and regulating hormones, but scientists have also focused on the impact of exercise on women with PCOS specifically [23].

Aerobic exercise. One study examined the effects of a 12-week intensified aerobic exercise intervention and found that the exercise improved insulin resistance in women with PCOS and lowered blood triglycerides more significantly than women without PCOS [24]. Another study revealed that 120 minutes of vigorous cardio per week was better than moderate cardio at improving insulin sensitivity and body composition [25].

HIIT training. In a small study comprising 31 women, researchers found that high intensity interval training (HIIT) 3 times per week for 10 weeks significantly improved insulin resistance [26].

Though the sample sizes are small, all three studies suggest short bursts of high intensity workouts and aerobic exercise can positively impact blood glucose levels in those with PCOS.

That being said, it’s essential to not overdo it when it comes to exercise, especially if you have PCOS. Vigorous workouts every day may lead to energy deficits and hormone imbalances, ultimately affecting period regularity [27]. These effects may further worsen PCOS symptoms.

If you’re unsure of how much (and how long) to work out, try starting with 120 minutes of low-intensity workouts such as jogging, cycling, or swimming every week — which nets out to four 30-minute sessions. You can then work your way up to more vigorous exercises. Remember: it’s best to get plenty of rest during the week and make sure you’re listening to your body. If you notice that you’re experiencing greater physical fatigue, irritability, trouble sleeping, or even weight gain, you may be overdoing your workouts [28].

Key takeaways

Although the cause is not known and the symptoms not clearly defined, PCOS is a disorder marked by the presence of cysts on the ovaries of childbearing-age women that can make it difficult for women to conceive and even lead to early pregnancy loss. Here are some key things to keep in mind if you’re struggling to manage insulin resistance associated with PCOS:

Focus on whole, unprocessed, low-GI foods to keep your blood glucose levels stable (which can reverse insulin resistance).
Eat anti-inflammatory foods such as colorful vegetables, whole fruits, and healthy fats to help mitigate the chronic inflammation that’s linked to PCOS.
Get at least 120 minutes of vigorous aerobic exercise per week (start with low-intensity or moderate exercise if you’re just starting out) to improve insulin sensitivity.
Do HIIT training 3 times per week for at least 10 weeks to help with insulin resistance.
Use a CGM to help you learn how your body responds to blood glucose and how to optimize your metabolic health with diet and exercise.

Michelle Severs is a science and health writer who explores the intersection between research and practice through oral and written media channels. She obtained a bachelor’s degree in Nutritional Sciences from Cornell University and a master’s degree in Nutrition Interventions, Communication, and Behavior Change from Tufts University. She is currently completing her dietetic internship at Vanderbilt University to become a Registered Dietitian. When not immersed in nutrition and dietetics, she enjoys playing, watching, and talking all things soccer.

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Written by: Michelle Severs, MS

Reviewed by: Emily Johnson, MSc RD

Table of Contents

What are PCOS symptoms and pathophysiology?
How does PCOS relate to metabolic health and insulin resistance?
How can managing glucose help with PCOS?
Key takeaways
References