Published on September 17, 2021

Study demonstrates beneficial effects of melatonin and magnesium co-supplementation on total testosterone, metabolic parameters, and sleep quality for women with PCOS

Key Points

  • Polycystic ovary syndrome (PCOS) is associated with endocrine and metabolic abnormalities, including high testosterone levels, hyperglycemia, insulin resistance, and abnormal cholesterol levels
  • Previous studies have shown a positive effect of either magnesium or melatonin on PCOS and sleep difficulties often suffered by women with PCOS
  • A randomized controlled trial looking at the effects of magnesium, melatonin, or the combination of both among women with PCOS found the greatest benefits after 8 weeks of magnesium and melatonin co-supplementation

Polycystic ovary syndrome (PCOS) is an endocrine disorder that can cause problems with the menstrual cycle and is thought to be directly related to insulin sensitivity and metabolic syndrome. It affects approximately 5-10% of women world-wide, with about 83% of these women also suffering from low fertility or infertility. PCOS causes symptoms that include the accumulation of small cysts on the ovaries, menstrual irregularities, anovulation or irregular ovulation, and other symptoms such as acne and weight issues.

PCOS is also associated with endocrine and metabolic abnormalities, namely those seen with metabolic syndrome, such as hyperinsulinemia, hyperglycemia, glucose intolerance, dyslipidemia, and obesity.

Certain factors are thought to contribute to the incidence of PCOS, such as genetics, environmental, and dietary factors. Some nutrients may also have an effect on PCOS, with one recent study showing a reduced risk of PCOS among women with higher intake and blood levels of omega-3 fatty acids.

Magnesium and Melatonin Supplementation Shown to Improve Markers Associated with PCOS

Melatonin is a powerful anti-oxidant that has been shown to have anti-cancer and anti-inflammatory effects, and play a role in regulating blood pressure and glucose levels. Previous studies on melatonin supplementation have also resulted in a significant reduction of total testosterone and improvement of menstrual irregularities among women with PCOS.

Magnesium has also been shown to affect insulin sensitivity and serum cholesterol and triglycerides, and studies have found magnesium deficiency may increase the risk of PCOS.

How Might the Combination of Melatonin and Magnesium Improve PCOS?

A recent randomized controlled trial by Alizadeh et al. enrolled 84 women with PCOS between the ages of 18 and 40 years old to see if supplementation with magnesium, melatonin, or magnesium plus melatonin had any effect on metabolic and hormonal blood markers related to PCOS, as well as an effect on the quality of sleep. Participants were randomized into four groups:

  • The magnesium and melatonin co-supplement group received two 3mg tablets of melatonin plus a 250 mg magnesium oxide tablet
  • The melatonin group received two 3mg tablets of melatonin plus a magnesium placebo
  • The magnesium group received a 250 mg magnesium oxide tablet plus two melatonin placebos
  • The placebo group received two melatonin placebos and a magnesium placebo

Blood samples were collected before the intervention and again after 8 weeks of supplementation.

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After 8 weeks, those taking both magnesium and melatonin had significantly improved quality of sleep, and reduced glucose homeostasis parameters, serum cholesterol, LDL-C, and testosterone levels, compared to baseline values. The magnesium plus melatonin group also saw a significant decrease in weight, BMI, and waist circumference from the beginning of the study to the end.

Those taking melatonin only also had improved quality of sleep and reduced testosterone levels, however, a greater improvement was seen in the group taking both melatonin and magnesium.

Vitamin D Might Also Help

Vitamin D has been linked to metabolic syndrome; in fact, women with vitamin D levels less than 20 ng/ml (50 nmol/L) had more than two times the risk of metabolic syndrome compared to women with levels at or above 30 ng/ml (75 nmol/L).

Measure Your Levels

Having and maintaining healthy vitamin D levels and other nutrient levels can help improve your health now and for your future. Choose which to measure, such as your vitamin D, omega-3s, and essential minerals including magnesium and zinc, by creating your custom home test kit today. Take steps to improve the status of each of these measurements to benefit your overall health. You can also track your own intakes, symptoms and results to see what works best for YOU.

Enroll and test your levels today, learn what steps to take to improve your status of vitamin D (see below) and other nutrients and blood markers, and take action! By enrolling in the GrassrootsHealth projects, you are not only contributing valuable information to everyone, you are also gaining knowledge about how you could improve your own health through measuring and tracking your nutrient status, and educating yourself on how to improve it.

Help everyone Move Research into Practice with vitamin D and other nutrients! As a special birthday gift to everyone, in honor of the science, we have created a special scholarship fund for anyone to donate to that will go towards helping others participate. Your donation will allow anyone to get help with funding their participation when they need it.

Text-to-give: Text Daction to 44321 to add to our Scholarship Fund.

What Does it Take YOU to Get Your D to 40 ng/ml (100 nmol/L)?

Did you know your health could be greatly affected by making sure you have a vitamin D level of at least 40 ng/ml (100 nmol/L)? Help us help you.

STEP 1 - Do you know what your vitamin D level is? If not, be sure to test today to find out.

STEP 2 – Determine your target level. Are you at your target level? Experts recommend a level of at least 40-60 ng/ml (100-150 nmol/L).

STEP 3 – Need to boost your level? Use the D*calculator to see how much vitamin D it may take to reach your target. Opt for the Loading Dose for a quicker boost.

STEP 4 – Optimize how your body absorbs and utilizes vitamin D with co-nutrients and these simple steps.

STEP 5 – Re-Test! This is an important step to make sure you have reached your target level, and to ensure you are not taking too much! Re-testing after 3-4 months is recommended.

STEP 6 – Adjust, Repeat…

Give your immune system the nutrients it needs to support a healthy you and protect yourself from unnecessary diseases, especially COVID-19.


The first Randomized Controlled Trial on vitamin D and COVID-19 has shown a 96% lower risk of ICU admission for those receiving vitamin D (as 25(OH)D to quickly boost vitamin D blood levels) along with the standard treatment, compared to those receiving standard treatment alone.

These results support many previous observational studies showing a relationship between vitamin D levels and intake and COVID-19 severity.

Review the Latest Nutrient Research for COVID-19

GrassrootsHealth Nutrient Research Institute has launched the new Immune Boost project with the use of our myData-myAnswers nutrient health system that nearly 15,000 people are already using for their health. Specific markers that influence immune health are suggested for testing as part of this project including:

  • Vitamin D
  • Omega-3 Index
  • Essential elements magnesium, selenium, and zinc
  • hsCRP

Our goal is to demonstrate how one can use the Nutrient Research Model established by Dr. Robert Heaney to show the effect of vitamin D serum levels of at least 40 ng/ml (100 nmol/L) on risk reduction for all ethnicities in the population. Status and intake of other nutrients will also be analyzed for any type of relationship to immune status and symptom severity. Join the project today!

Please let us know if you're interested in helping sponsor this project.

CLICK HERE for updates and new information about the project.

Through GrassrootsHealth Nutrient Research Institute, you can also test your essential elements magnesium, copper, zinc and selenium, toxins such as lead, mercury and cadmium, as well as your omega-3 levels, inflammation levels and thyroid stimulating hormone (TSH) level. Find out your levels today! Log on to the test selection page (click the link below) to get your tests and see for yourself if your levels can be improved.

Make sure you track your results before and after, about every 6 months!

Click Here to Access the Test Page

How can I track my nutrient intake and levels over time?

To help you track your supplement use and nutrient levels, GrassrootsHealth has created the Personal Health Nutrient Decision System called

For each specific supplement, you can track what days you take it, how much, and many other details.  This will help you know your true supplemental intake and what patterns of use work for you to reach and maintain optimum nutrient levels. Check it out today!