PCOS Isn’t Just a Hormone Problem—It’s a Gut Problem, Too

By Dr. Stephanie Yakupitiyage, ND

When discussing PCOS, most people immediately think of hormones, high testosterone, irregular cycles, acne, and infertility. But, there’s a piece that often gets missed: the gut.

Your gut directly influences sex hormones and insulin signaling. So, if the gut is inflamed, imbalanced, or lacking diversity, hormones will not regulate properly. This is why so many women feel stuck in a vicious cycle when treating PCOS. They try to “fix hormones” yet the symptoms don’t improve.

Research shows that women with PCOS have reduced gut microbial diversity—the lower the diversity, the higher the androgen (testosterone) levels tend to be. Also, PCOS patients are likely to have elevated zonulin levels (think: the glue between your gut cells that keeps unwanted substances from entering circulation). While low zonulin levels tighten gut permeability, higher zonulin levels loosen the gut barrier, resulting in a leaky gut. In PCOS, high zonulin involves insulin resistance and inflammation. This inflammation doesn’t stay in the gut; it spills over into the ovaries and contributes to ovarian inflammation, which further contributes to infertility.

According to one study, when researchers transferred gut bacteria from women with PCOS into rats, the rats went on to develop high androgens and PCOS-like features. That’s how powerful the gut microbiome is. Every major pathway involved in PCOS, insulin resistance, inflammation, androgen excess, and ovulation intersects with the gut.

This is why you NEED to treat the gut microbiome to truly escape the PCOS cycle. A foundational starting point is fiber. Diversity matters—different fibers feed different beneficial bacteria, and more diversity leads to better hormone metabolism and insulin sensitivity. One supplement I really like is Fiber MGP by Ortho Molecular because it provides a variety of types of fibers to support microbial diversity. It also helps to stimulate GLP-1 signaling which is important because GLP-1 plays a role in blood sugar regulation and insulin sensitivity. Supporting GLP naturally through fiber can help calm insulin resistance and assist in treating PCOS symptoms. It can even help with common GI symptoms, such as bloating and constipation.

Supporting the gut is not an extra step in a treatment plan—it’s foundational.