Is there a link between PCOS and SBHG?
Studies have revealed that women with polycystic ovarian syndrome (PCOS) usually present low levels of sex hormone-binding globulin (SHBG). SHBG is believed to be linked to insulin resistance, which is frequently found in women with PCOS, so let’s take a look at the two conditions and the links between them.
Polycystic ovary syndrome is a common condition that affects the way our ovaries work. It’s believed to affect around 20% of women, although more than half are unaware that they have it, and do not experience symptoms. The three main features are irregular periods, excess androgen (‘male’ hormones, which can cause excess facial or body hair) and polycystic (enlarged and containing follicles) ovaries. Other symptoms may include weight gain, infertility, fatigue, mood swings, adult acne, fluid retention, and prolonged or absent periods. While the exact cause of PCOS isn’t known, it is often linked to abnormal hormone levels, including high insulin.
Sex hormone-binding globulin is a protein that is primarily generated by the liver, while smaller quantities are produced by the brain, uterus, and placenta. SHBG binds ‘sex hormones’ in the blood, reducing circulating levels of ‘free hormones’. When SHBG levels drop, levels of free testosterone rise. Women who have PCOS often have elevated testosterone levels, which suggests there is a strong link between the two conditions. While SHGB doesn’t present symptoms in itself, conditions such as insulin resistance, obesity, and PCOS can help to identify it.
The insulin link
The body produces insulin when glucose is released into the bloodstream while digesting carbohydrates. This normally leads to the glucose being stored in the body’s cells to be used for energy, which decreases the concentration of glucose in the blood, so that it stays within a normal range. Insulin resistance (IR) occurs when the body’s cells are unable to use this insulin effectively, which leads to high blood sugar levels. The pancreas produces additional insulin, which adds to the problem. IR can lead to type 2 diabetes, latent autoimmune diabetes, and increased cardiovascular risk.
Insulin resistance is believed to play an important role in PCOS. As SHBG levels are reduced when IR occurs, tests that measure certain markers are a reliable indicator of insulin resistance, and an important tool in diagnosing PCOS. Those markers include Hemoglobin A1C (should be under 5.5); adiponectin (should be over 6); and fasting glucose (under 100); fasting insulin (ideally under 10). IR is believed to reduce the liver’s production of SHBG while substantially increasing androgen production in the ovaries. This double hormone influx often manifests in the form of the PCOS symptoms discussed above.
Even a slight increase in testosterone can create a hormone imbalance, so it’s important that you get your SHBG levels checked in addition to some of the markers mentioned here if you are experiencing any of the symptoms described in this blog. If you have low SHBG levels (and therefore elevated testosterone levels), it may be worth considering PCOS as the cause for your complaints.
There are various ways to treat these conditions, and different types of doctors will likely recommend different strategies. A traditional medical practitioner might prescribe medication (for example birth control pills, anti-androgens, or estrogen replacement therapy to address hormone imbalance, or Metformin to counter insulin resistance). Meanwhile, an integrative medical practitioner might encourage you to alter your diet and exercise habits and to add certain nutritional supplements (for example Vitamin D, flaxseed, fish oils, and berberine) to help redress the imbalance. I am a firm believer in making simple healthy lifestyle choices to correct problems such as insulin resistance. A diet low in refined carbohydrates and grains can be helpful.
The key to correcting your low SHBG levels and/or PCOS condition is to find a doctor who will consider your symptoms collectively and treat the whole body rather than simply keeping your symptoms at bay. A functional or integrative medical practitioner will do this, and the knock-on benefit is that you should also feel better in other areas of your body, mind, and soul!