Why vitamin D and calcium are important for PCOS

Vitamin D and calcium are often-discussed for their immune and bone health benefits. But did you know they can also improve hormonal health?

Polycystic ovary syndrome, also known as PCOS, is a condition in which the ovaries produce an excess amount of androgen, a male sex hormone that is present in women only in small amounts. PCOS is the most common cause of infertility in women (1).

However, PCOS may cause a multitude of other symptoms including but not limited to insulin resistance which may increase the risk of developing type 2 diabetes and more severe symptoms (2). PCOS can also increase risk for serious health conditions such as stroke, cardiovascular disease, and endometrial cancer, not to mention bothersome day-to-day symptoms such as irregular menstrual cycles, acne, hair loss, hirsutism, and more.

While the exact cause of PCOS is unknown, there is much that can be done to optimize our current and future health through learning how to better control our symptoms. Conventional treatments for PCOS include hormonal birth control and diabetes medication such as metformin (1). However, many people find that lifestyle-based and holistic strategies can also help alleviate their PCOS symptoms.

While foundational items such as eating a nutrient-dense diet, moving your body, getting enough sleep, and managing stress can typically improve symptoms significantly, if you have found your progress has plateaued or if you have a more sever case of PCOS you may find adding targeted vitamins and supplements to your diet will be a help.

In this article we'll be focusing on the importance of vitamin D and calcium when it comes to managing PCOS.

Why Vitamins D and Calcium are important for PCOS

Vitamin D and calcium are often-discussed for their immune and bone health benefits. But did you know they can also improve hormonal health?

In general, vitamin D may help fight off disease, prevent osteoporosis, reduce depression, and promote bone health. While calcium is also beneficial for bone health, it may also prevent diabetes, high blood pressure, and cancer.

It has been shown that people with PCOS also tend to have a deficiency in vitamin D which can increase insulin resistance and other symptoms associated with PCOS (3). Therefore, people with PCOS need to have their vitamin D levels evaluated by a healthcare professional. In addition, vitamin D and calcium work best together since vitamin D is needed to absorb calcium.

Studies have shown vitamin D and calcium to have positive results in women diagnosed with PCOS. 

A study published in Complementary Therapies in Clinical Practice evaluated the benefits of calcium and vitamin D supplementation in infertile women diagnosed with PCOS. 100 women were studied and randomly divided into two groups. The first group was treated with 1,500 mg of metformin per day and the second group was treated with 1,500 mg of metformin per day, 100 mg of calcium per day, and 100,000 IU/month of vitamin D for 6 months (4). 

Patients were monitored by transvaginal sonography at the beginning of the study, after three months, and lastly at six months. The study showed the group being treated with vitamin D and calcium alongside metformin to have an improvement in menstrual cycles, follicle maturation, and infertility (4). 

Adding vitamin D and calcium to your day

Since vitamin D and calcium are both fat soluble vitamins, you actually can have too much because your body cannot urinate out excess amounts. For this reason, be sure to consult your healthcare provider before starting to take vitamin D or calcium supplements. Beyond supplementation, vitamin D and calcium can also be found in a variety of foods.

Vitamin Dis most effectively absorbed with sun exposure. While it varies by source, it is typically recommended to get a few minutes of sun exposure in the morning or late afternoon when UV rays are not strong, as SPF actually blocks vitamin D absorption.

We can also absorb vitamin D naturally from foods. Some foods high in vitamin D include:

- Fatty fish such as salmon

- Eggs

- Mushrooms

Getting enough vitamin D increases chances of proper calcium absorption. Foods rich in calcium include:

- Chia seeds

- Yogurt and other grass-fed dairy

- Legumes like beans and lentils

- Almonds

- Leafy green vegetables

Remember to speak to your healthcare professional before starting any supplement or following a specific diet.


1. Centers for Disease Control and Prevention. (2020, March 24). PCOS (polycystic ovary syndrome) and diabetes. Centers for Disease Control and Prevention. Retrieved December 9, 2021, from https://www.cdc.gov/diabetes/basics/pcos.html.

2. Polycystic ovary syndrome (PCOS). Johns Hopkins Medicine. (n.d.). Retrieved December 9, 2021, from https://www.hopkinsmedicine.org/health/conditions-and-diseases/polycystic-ovary-syndrome-pcos.

3. Thomson, R. L., Spedding, S., & Buckley, J. D. (2012). Vitamin D in the Aetiology and management of polycystic ovary syndrome. Clinical Endocrinology, 77(3), 343–350. https://doi.org/10.1111/j.1365-2265.2012.04434.x 

4. Firouzabadi, R. dehghani, Aflatoonian, A., Modarresi, S., Sekhavat, L., & MohammadTaheri, S. (2012). Therapeutic effects of calcium & vitamin D supplementation in women with PCOS. Complementary Therapies in Clinical Practice, 18(2), 85–88. https://doi.org/10.1016/j.ctcp.2012.01.005






Simona Carputo


Simona is a Certified Health Education Specialist specializing in nutrition and health education. Simona is passionate about helping others develop a healthy relationship with food and manage chronic health conditions by implementing a non-restrictive approach to health.