PCOS is an endocrine disorder in women of reproductive age characterized by a range of symptoms, including irregular periods, ovarian cysts, excessive hair growth (hirsutism), acne, and weight gain. It has been associated with metabolic and hormonal abnormalities like high cholesterol, insulin resistance, inflammation, and hyperandrogenism— an excess amount of sex hormones called androgens, like testosterone. It is also the most common cause of female infertility, impacting 6-10% of women of childbearing age.
Medical treatment for PCOS is often based on the individual’s symptoms. Dietary and lifestyle changes are often the first line of defense in helping to manage PCOS symptoms. While evidence suggests that a well-balanced diet rich in nutrient-dense foods is key, there are a few nutrients to pay extra attention to with PCOS. We recommend trying to get most of these nutrients from food, however there are some cases where supplementation may be beneficial.
For a deep dive into nutrition strategies for PCOS—like how to build meals that address insulin resistance and even promote weight loss—be sure to check out this blog post.
7 key nutrients for PCOS
Inositol is a sugar naturally found in fruits like grapefruit and cantaloupe, whole grains, beans, and nuts. It is one of the most widely researched supplements for PCOS.
The two primary forms of inositol are myo-inositol (MI) and D-chiro-inositol (DCI). PCOS appears to involve an increase in the conversion of MI to DCI in the ovary by insulin, leading to the overproduction of DCI and MI deficiency. This process results in a disruption in follicle-stimulating hormone signaling and lower-quality oocytes—immature egg cells involved in reproduction. Inositols may help restore spontaneous ovulation, improve fertility, and regulate the menstrual cycle.
Evidence indicates a 40:1 ratio of D-chiro inositol to myo-inositol, found in supplemental form, is the most beneficial in restoring ovulation and improving metabolic parameters.
Inositol supplementation has also shown promise in improving insulin resistance and other markers of metabolic health, like cholesterol and triglycerides, which are often elevated in women with PCOS. It has been proposed that insulin resistance in PCOS may be related to a deficiency in an insulin signaling pathway that requires inositol. Supplementation with inositol has been shown to improve insulin sensitivity and glucose tolerance. A study evaluating the effects of myo-inositol in women with PCOS showed improvement in ovarian function, HDL cholesterol—often referred to as “good” cholesterol—and reduction in BMI in participants taking 2g of myo-inositol in combination with folic acid daily.
Omega-3 fatty acids
Omega-3 fatty acids are essential for making hormones that regulate blood clotting, contraction and relaxation of the artery walls, and reducing inflammation in the body. They can help to prevent heart disease and stroke, amongst other pro-inflammatory conditions. Research has shown improvements in cholesterol, waist circumference, and regulation of menstrual cycles with omega-3 supplementation in women with PCOS.
Since the body does not make omega-3 fats, we must get them from food. The best sources of omega-3 are fatty fish like salmon, tuna, anchovy, sardines, trout, oysters, and plant-based foods like flaxseed, flax oil, and walnuts. If these foods aren’t consistently included in your diet a few times a week, a fish oil supplement containing both EPA and DHA—forms of omega 3— may be recommended.
Vitamin D is a fat-soluble vitamin that plays a role in bone health, immunity, fertility, reducing inflammation, and blood sugar regulation. It is found in foods like dairy products, eggs, and fatty fish like salmon and tuna. It is also produced in the body through exposure to the sun.
Deficiency is common, especially in the winter, with less sunlight exposure. We recommend asking your doctor to add a vitamin D test with other routine blood work to monitor levels periodically. Most multivitamins will contain the daily recommended amount, but it may be necessary to supplement with additional vitamin D if you have limited sun exposure, are not regularly consuming vitamin D-rich food sources, or have a history of deficiency. Vitamin D deficiency has been associated with insulin resistance and high androgen levels in women with PCOS.
Vitamin D supplementation in those with low levels improved insulin resistance and reduced total testosterone levels in women with PCOS.
Coezyme Q10 (ubiquinone) is a coenzyme—a compound necessary for enzymes to function—primarily known for its antioxidant properties. It has been used as a dietary supplement for cardiovascular disease, high cholesterol, diabetes, and cancer. Combined with vitamin E supplementation, CoQ10 reduced fasting plasma glucose levels and serum insulin concentrations in women with PCOS.
CoQ10 is often used as a supplement in those with infertility. Supplementation in one study was associated with a higher number of mature follicles, greater endometrial thickness, and higher serum concentrations of progesterone and estradiol in women with PCOS, resulting in improved ovulation and pregnancy rates in those trying to conceive.
Food sources of CoQ10 include fatty fish like salmon and tuna, beef, nuts and seeds, and whole grains.
Curcumin is a substance found in the spice turmeric that has antioxidant and anti-inflammatory properties. It has been shown to improve glycemic control by decreasing fasting blood glucose and increasing insulin sensitivity in patients with PCOS. In one study, patients with PCOS taking curcumin had better glycemic control and HDL cholesterol than those taking a placebo.
Cooking with turmeric in combination with black pepper—which increases its absorption by a whopping 2,000%—is a great way to get the benefits of this anti-inflammatory compound. Add it to some roasted cauliflower, soups, curries, or steep in a turmeric tea. It can also be found in supplement form. It’s important to note curcumin supplements should not be taken during pregnancy or while breastfeeding.
Magnesium is a nutrient involved in many processes in the body, including regulating blood sugar and blood pressure, nerve and muscle function, protein synthesis, and bone health. Inadequate magnesium intake has been associated with high blood pressure, cardiovascular disease, and type 2 diabetes.
According to several dietary surveys looking at magnesium intake in the U.S., on average, people consume less than the Recommended Daily Allowance (RDA) of 320-420 mg/day. Over 50% of the population is estimated to have at least a marginal magnesium deficiency.
Lower levels of magnesium in the blood have been associated with a higher degree of insulin resistance and elevated testosterone levels among women with PCOS. Magnesium supplementation of 250 mg over an 8 week period in this study resulted in reduced levels of testosterone in the blood; however, there was no observed improvement in glycemic control.
Sources of magnesium-rich foods include leafy green vegetables, beans, legumes, nuts, seeds, and avocados. Magnesium can also be taken supplementally to increase levels if dietary intake is low.
Spearmint, specifically spearmint tea
Spearmint is an herb commonly used to infuse toothpastes and gums, but it has benefits beyond just freshening breath. Spearmint has anti-inflammatory, antioxidant, and antimicrobial properties and has been shown to have anti-androgen effects in women with PCOS—meaning it may have a positive effect on reducing levels of androgen hormones, like testosterone. In one study, free and total testosterone levels were reduced in individuals who consumed spearmint tea twice per day for one month when compared to a placebo. Participants in this study also noted a reduction in their hirsutism, or undesired hair growth, which is often the result of excess androgens.
PCOS is a complex condition with symptoms that are often difficult to manage. Diet and lifestyle are essential factors in helping to mitigate these frustrating symptoms. Focusing on specific nutrients and supplementing where necessary can be a beneficial addition to a current treatment plan. For an in depth look at other nutrition principles for individuals with PCOS, check out this blog post on the best nutrition plans for PCOS patients who want to lose weight.
When you’re on the market for any new dietary supplements, look for the “third-party assessed” stamp. This means a third party, an organization not associated with the supplement brand, has tested it for quality and purity.
Remember to always consult with your healthcare before starting any new supplements. For a personalized nutrition plan, ask your Care Coordinator about a visit with one of the Sequence Registered Dietitians.
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