by Amy Medling, founder of PCOS Diva
Polycystic Ovarian Syndrome (PCOS) is one of the most common endocrine disorders found in women, affecting approximately 5-10% of women worldwide, with less than 50% of them diagnosed. The syndrome is present throughout a woman’s life from puberty through post-menopause and affects women of all races and ethnic groups. Women with PCOS wrestle with an array of possible symptoms including obesity, irregular menstrual cycles, infertility, depression, weight gain, insulin resistance, acne, hair loss, and more. Recent studies indicate that quercetin may help resolve many PCOS symptoms.
There are a lot of supplements that can help PCOS patients manage their symptoms, and one of them is a polyphenol called quercetin. I was excited to read a review of Quercitin studies in PCOS published in the Journal of Ovarian Research. In it, researchers investigated the efficacy of quercetin supplementation in patients with PCOS.
This review included a combination of three human clinical trials and five animal studies evaluating the effects of quercetin in PCOS. These studies showed that quercetin supplementation increases normal follicles in ovaries, restores the normal ovary anatomy, and improves histology in the uterus, at a rate that is comparable to or better than metformin. Quercetin was also shown to reduce testosterone levels, luteinizing hormone (LH), and improve insulin resistance and dyslipidemia in seven of the eight studies. Hirsutism was only evaluated in two studies; however, both studies showed that quercetin improved the condition.
This review demonstrates that quercetin can help correct hormonal dysfunction and improve some of the metabolic features of PCOS through its antioxidant and anti-inflammatory properties. So, what is quercetin and how do we get it?
What is Quercetin?
Quercetin is a polyphenol and natural pigment found in many fruits, vegetables, grain, and even wine.
Because of its ubiquity, quercetin is considered one of the most abundant antioxidants in our diet, and researchers estimate that the average human consumes between 10 mg to 100 mg of quercetin a day. This is critical because quercetin is involved in many processes that are meant to protect our body from free radical damage which damages most every type of cell.
More than just a powerful antioxidant, quercetin has been cited for its anti-inflammatory properties, benefits for allergy symptoms, and blood pressure management. Because of its natural and healthy properties, quercetin has been cited for its potential in lowering the risks of heart disease, cancers, and even degenerative brain disorders such as dementia and Alzheimer’s.
What quercetin can do for PCOS symptoms
Two of the main drivers of PCOS symptoms are insulin resistance and chronic inflammation.
Insulin resistance is a condition where your body is no longer able to efficiently remove glucose from the bloodstream which can lead to a plethora of diseases, most notably Type 2 Diabetes and heart disease.
Chronic inflammation, on the other hand, is a state of the body where it feels constantly stressed or attacked, which can lead to a slow, yet gradual damage to tissues and organs. Many researchers say chronic inflammation is the one cause that links almost every disease known to humans – from asthma and diabetes to arthritis and cancer.
Quercetin is known to possess anti-inflammatory properties as well as have some benefits for blood sugar management. Here are what studies have to say about them:
On chronic inflammation
As mentioned earlier, chronic inflammation is what many researchers consider the common denominator for almost every disease known to humans. For women with PCOS, symptoms are associated with inflammation whether it is a hormonal imbalance or insulin resistance.
Quercetin has been cited for its anti-inflammatory properties in various studies. Here are some of them:
- Test-tube studies show quercetin can markedly reduce inflammation in human cells. In actual human subjects, quercetin has been shown to inhibit biomarkers of inflammation.
- Women with rheumatoid arthritis took 500 mg of quercetin for 8 weeks. The participants noted reduced early morning stiffness as well as a reduction in the general perception of pain.
- Researchers reviewed the therapeutic and anti-inflammatory properties of quercetin on obesity and type 2 diabetes.
- On obesity, researchers noted that quercetin reduced fat formation by reducing fat-forming enzyme activity.
- On diabetes, quercetin was shown to stimulate the glucose-scavenging property of insulin.
Women with PCOS have too much-circulating testosterone which causes ovulation and menstruation irregularities.
Quercetin has been cited to help reduce levels of testosterone as well as luteinizing hormone – a reproductive hormone that plays a major role in controlling the function of ovaries. In a recently published review, researchers concluded that supplementing with quercetin can effectively reduce not only testosterone levels, but also symptoms of hyperandrogenemia – a condition known to cause irregular menstruation, hirsutism, and acne.
Insulin resistance and obesity
One of the most common symptoms of PCOS is insulin resistance which puts women at risk for obesity, high blood sugar levels, Type 2 Diabetes, and heart disease. Quercetin has been cited to help improve insulin sensitivity which can help reduce the risks of heart disease as well as obesity.
- Quercetin has been observed to exhibit anti-diabetic properties in various experiments. Researchers suggest that polyphenol works by inhibiting intestinal glucose uptake as well as alpha-glucosidase activity. Alpha-glucosidase is an enzyme that splits glucose from starch, so reducing this enzyme’s activity would result in lower blood sugar levels.
- In a trial involving 84 PCOS patients, the experiment group was asked to take 1, 000 mg quercetin daily for 12 weeks while the other group received a placebo. The patients who took quercetin showed increased activity of hormones that help burn fat.
High Uric Acid
One more thing Quercetin is suitable for is treating hyperuricemia.
What is Hyperuricemia?
Hyperuricemia is when your uric acid levels are too high, leading to gout and kidney stones. The leading cause of hyperuricemia is high purine content, a chemical found in certain foods.
About 1 in 5 people you encounter have high uric acid levels, but they don’t always result in gout. It’s common to have high uric acid and not have any symptoms. This is referred to as asymptomatic hyperuricemia and requires no medication.
Hyperuricemia and PCOS
A 2018 study found that women with PCOS are more likely to have high uric acid levels. The study observed over 11,000 women and found that in women with PCOS, 25.8% have high uric acid, while only 8.74% of those without PCOS had hyperuricemia.
Experts also noted a high prevalence of hyperuricemia in PCOS women who were obese (58.75%), suggesting those who managed to keep their weight to a normal BMI range aren’t likely to have high uric acid levels.
They also noted how androgen excess might contribute to high serum uric acid. Androgens can increase uric acid levels by promoting purine metabolism, enhancing purine turnover in the kidney, and leading to high uric acid content.
Excess androgen is a common characteristic of PCOS.
“PCOS with hyperandrogenism had higher uric acid level than PCOS with anovulation and polycystic ovaries.” 
Free testosterone was also positively correlated with serum uric acid levels regardless of age or BMI.
Quercetin and Hyperuricemia
In his blog, Dr. Perlmutter discusses the uric acid-lowering effects of Quercetin and how it synergizes with vitamin C, luteolin, and tart cherry when managing hyperuricemia.
A 2016 study found that Quercetin inhibits xanthine oxidoreductase, the final step in uric acid production. 
The study was conducted on males diagnosed with pre-hyperuricemia who were asked to take 500 mg of quercetin for four weeks. Once the experiment was over, researchers found that 4 weeks of oral quercetin supplementation significantly reduced uric acid levels up to -45.5 µmol/L.
It should be noted that the healthy uric acid range for men is around 208-428 µmol/L and 155-357 µmol/L in women. Therefore, a 45.5 decrease is equivalent to over 10% of the upper limit.
Good dietary sources of quercetin for PCOS
If your diet is similar to most people’s, you’re probably getting anywhere from 10 mg to 100 mg of quercetin a day. In order to increase your dietary quercetin dose, consider adding foods known to have high amounts of quercetin.
- Peppers, both yellow and green
- Red and white onions
- Cooked asparagus
- Red leaf lettuce
- All types of berries
- Green and black tea
Supplementing with quercetin
You may also choose to supplement with quercetin. When choosing a supplement, be certain that it is third-party certified, so you know that you are truly getting the nutrients indicated on the label. PCOS Diva Defense, for example, contains 500mg of quercetin and is GMP certified quality. Resveratrol Plus also contains 200mg Quercetin.
Amy Medling, 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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- Javadi F, Ahmadzadeh A, Eghtesadi S, et al. The Effect of Quercetin on Inflammatory Factors and Clinical Symptoms in Women with Rheumatoid Arthritis: A Double-Blind, Randomized Controlled Trial. J Am Coll Nutr. 2017;36(1):9-15. doi:10.1080/07315724.2016.1140093
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- Kim JH, Kang MJ, Choi HN, Jeong SM, Lee YM, Kim JI. Quercetin attenuates fasting and postprandial hyperglycemia in animal models of diabetes mellitus. Nutr Res Pract. 2011;5(2):107-111. doi:10.4162/nrp.2011.5.2.107
- Rezvan N, Moini A, Gorgani-Firuzjaee S, Hosseinzadeh-Attar MJ. Oral Quercetin Supplementation Enhances Adiponectin Receptor Transcript Expression in Polycystic Ovary Syndrome Patients: A Randomized Placebo-Controlled Double-Blind Clinical Trial. Cell J. 2018;19(4):627-633. doi:10.22074/cellj.2018.4577
- Pourteymour Fard Tabrizi F, Hajizadeh-Sharafabad F, Vaezi M, Jafari-Vayghan H, Alizadeh M, Maleki V. Quercetin and polycystic ovary syndrome, current evidence and future directions: a systematic review. J Ovarian Res. 2020;13(1):11. Published 2020 Jan 31. doi:10.1186/s13048-020-0616-z
- Mu L, Pan J, Yang L, et al. Association between the prevalence of hyperuricemia and reproductive hormones in polycystic ovary syndrome. Reprod Biol Endocrinol. 2018;16(1):104. Published 2018 Oct 25. doi:10.1186/s12958-018-0419-x
- Shi Y, Williamson G. Quercetin lowers plasma uric acid in pre-hyperuricaemic males: a randomised, double-blinded, placebo-controlled, cross-over trial. Br J Nutr. 2016 Mar 14;115(5):800-6. doi: 10.1017/S0007114515005310. Epub 2016 Jan 20. PMID: 26785820.