Researchers reviewed 78 studies about using natural supplements to help women with PCOS (a common hormone condition). They found that certain supplements like vitamin D, inositol, and quercetin may help lower insulin levels and balance hormones when used alongside regular treatment. The supplements appeared to work best for improving blood sugar control and hormone levels, though results were mixed for other fertility-related measures. While these findings are promising, researchers note that more high-quality studies are needed to fully understand how well these supplements work and for whom they work best.

The Quick Take

  • What they studied: Whether natural supplements and food-based compounds can help improve hormone balance and fertility in women with PCOS (polycystic ovary syndrome)
  • Who participated: Analysis of 78 different research studies involving women with PCOS who took various supplements or received standard treatment
  • Key finding: Supplements significantly lowered insulin levels and a hormone called LH, while raising SHBG (a protein that helps regulate hormones). Vitamin D showed the strongest benefits overall.
  • What it means for you: If you have PCOS, certain supplements may help your body manage insulin and hormones better when combined with lifestyle changes and medical treatment. However, talk to your doctor before starting any new supplement, as results vary between individuals.

The Research Details

This was a systematic review and meta-analysis, which means researchers searched five major medical databases for all studies published between 2013 and 2024 about supplements for PCOS. They found 78 studies that met their quality standards. The researchers then combined the results from these studies to see what patterns emerged about which supplements worked best and for what outcomes.

The team looked specifically at studies testing supplements like vitamin D, inositol (a natural sugar compound), quercetin (a plant chemical), and other bioactive compounds—basically powerful substances found in foods or made into pills that do more than just provide basic nutrition. They only included studies where some women got the supplement and others got a placebo (fake pill) or standard care, so they could fairly compare results.

Each study was checked for quality using standard scientific tools, and the researchers rated how confident they were in each finding using a system called GRADE (Grading of Recommendations Assessment, Development and Evaluation).

This approach matters because PCOS affects millions of women and causes problems with irregular periods, fertility, and metabolic issues like insulin resistance. By combining results from many studies, researchers can see the bigger picture of whether supplements actually help, rather than relying on just one small study. This type of analysis helps doctors and patients make better-informed decisions about whether to use supplements alongside standard treatments.

The study was registered in advance (PROSPERO), which means the researchers planned their analysis before looking at results—this prevents bias. They followed strict international guidelines (PRISMA 2020) for conducting and reporting systematic reviews. However, the researchers noted that the 78 studies they reviewed had different designs, tested different supplements, and measured different outcomes, which makes it harder to draw firm conclusions. Some studies were higher quality than others, which affects how much we can trust the overall results.

What the Results Show

The analysis found that supplements significantly reduced fasting insulin levels (the amount of insulin in your blood when you haven’t eaten), which is important because high insulin is a major problem in PCOS. On average, women taking supplements had insulin levels that were about 2 units lower than those not taking them.

Supplements also lowered luteinizing hormone (LH), a hormone that’s often too high in women with PCOS and contributes to irregular periods and fertility problems. The reduction was about 1.3 units on average. At the same time, supplements increased SHBG (sex-hormone-binding globulin), a protein that helps regulate hormones in the body—this is beneficial because higher SHBG helps balance hormones.

Vitamin D supplementation stood out as the most effective supplement for improving both metabolic health (how your body processes sugar and energy) and hormone balance. This makes sense because many women with PCOS have low vitamin D levels, and vitamin D plays important roles in insulin function and hormone regulation.

The results for other outcomes were less clear. When researchers looked at ovarian follicle count (the number of small sacs in the ovaries that contain eggs) and menstrual bleeding patterns, the results were inconsistent across studies. Some studies showed improvements, while others didn’t, suggesting that supplements may not reliably help with these specific fertility measures, or that different supplements work differently for different women.

This analysis builds on previous smaller studies that suggested supplements might help PCOS. By combining 78 studies, it provides stronger evidence that at least some supplements—particularly vitamin D and inositol—do have measurable effects on insulin and hormones. However, the findings confirm what many researchers suspected: we still need better-designed studies to know exactly which supplements work best for which women and at what doses.

The main limitation is that the 78 studies tested different supplements, used different doses, studied women with different characteristics, and measured outcomes in different ways. This ‘apples and oranges’ problem makes it harder to draw firm conclusions. Additionally, some studies were small or had design flaws that could have affected results. The researchers couldn’t find information about whether external funding influenced any studies, which is important to know. Finally, the analysis couldn’t determine which women are most likely to benefit from supplements or whether supplements work as well as other treatments.

The Bottom Line

If you have PCOS, discuss with your doctor whether vitamin D supplementation might help you, especially if you have low vitamin D levels (which is common in PCOS). Inositol supplements also show promise and may be worth discussing. However, supplements should complement—not replace—lifestyle changes like regular exercise, balanced nutrition, and stress management, plus any medications your doctor prescribes. Start with one supplement at a time so you can tell if it’s helping. Confidence level: Moderate for vitamin D and inositol; Lower for other supplements.

Women with PCOS who want to improve hormone balance and insulin control should pay attention to these findings. Women trying to conceive with PCOS may be particularly interested. However, these findings don’t necessarily apply to women without PCOS or men. Pregnant women should consult their doctor before taking any supplements. If you have other health conditions or take medications, check with your doctor before starting supplements, as they can interact with medications.

Most studies lasted 8-12 weeks, so you might expect to see changes in blood work (insulin and hormone levels) within 2-3 months of consistent supplementation. However, changes in menstrual regularity or fertility may take longer—typically 3-6 months or more. Individual results vary significantly, so patience and consistent use are important.

Want to Apply This Research?

  • Track daily supplement intake (vitamin D, inositol, or other supplements you’re taking) and correlate with menstrual cycle regularity. Log the first day of each period and note any changes in cycle length or symptoms like acne or hair growth over 3-month periods.
  • Set a daily reminder to take your supplement at the same time each day (ideally with a meal for better absorption). Use the app to log which supplement you’re taking, the dose, and any side effects. This helps you stay consistent and provides data to discuss with your doctor.
  • Every 3 months, review your menstrual cycle patterns, energy levels, and skin/hair changes. If your doctor orders blood work, log your insulin and hormone levels in the app to track improvements over 6-12 months. This long-term tracking helps you and your doctor determine if the supplement is actually helping you personally.

This research summary is for educational purposes only and should not replace professional medical advice. PCOS is a complex condition that requires individualized treatment. Before starting any supplement, consult with your doctor or a registered dietitian, especially if you’re pregnant, breastfeeding, taking medications, or have other health conditions. Supplements are not regulated the same way as medications and may interact with drugs or other supplements. The findings presented here represent trends across multiple studies but may not apply to every individual. Your doctor can help determine which supplements, if any, are appropriate for your specific situation and can monitor your progress with blood tests.