Sex Hormone Binding Globulin (SHBG): What It Is and Why It Matters

Sex Hormone Binding Globulin (SHBG): What It Is and Why It Matters

When it comes to understanding your hormonal health, most people are familiar with the key players like estrogen, testosterone, and progesterone. But there’s another crucial hormone regulator that often flies under the radar—Sex Hormone Binding Globulin (SHBG).

What is SHBG?

SHBG is a protein produced primarily by your liver. Its main function is to bind to sex hormones like testosterone, estrogen, and dihydrotestosterone (DHT) in your bloodstream. When hormones are bound to SHBG, they’re not available for use by your cells. In other words, SHBG controls how much “free” or active hormones are circulating in your body and are able to bind to receptors to carry out their functions.

Why SHBG Levels Matter

Your SHBG levels play a critical role in determining the balance between your bound and free hormones. Too much or too little SHBG can lead to hormone imbalances that affect everything from metabolism to mood.

• Low SHBG Levels

  • Low levels of SHBG can result in excess free hormones, particularly testosterone. For women, this can lead to symptoms like acne, excess facial or body hair (hirsutism), and irregular menstrual cycles—common symptoms in conditions like Polycystic Ovarian Syndrome (PCOS). For men, low SHBG may contribute to symptoms of testosterone dominance, which can include aggression, mood swings, and even an increased risk of heart disease.

• High SHBG Levels

  • On the flip side, when SHBG levels are too high, there may not be enough free testosterone or estrogen available for your body to use. In women, high SHBG levels can contribute to symptoms of estrogen deficiency like low libido, fatigue, and difficulty building muscle. Men may experience low testosterone symptoms, such as reduced energy, decreased muscle mass, and low sex drive.

Factors That Influence SHBG Levels

Several factors can affect your SHBG levels, making it essential to monitor them as part of your overall hormonal health.

• Hormonal Birth Control

  • Hormonal contraceptives, especially those containing synthetic estrogens, tend to increase SHBG levels. This can lower the availability of free testosterone and other sex hormones, contributing to side effects like decreased libido, mood swings, and weight gain.

• Insulin Resistance

  • Conditions like insulin resistance and type 2 diabetes are known to lower SHBG levels, which can lead to increased free testosterone in women and exacerbate symptoms of PCOS.

• Thyroid Health

  • Hypothyroidism (underactive thyroid) can also reduce SHBG levels, while hyperthyroidism (overactive thyroid) tends to increase them. This can lead to imbalances that contribute to a range of symptoms, from low energy to anxiety.

• Liver Health

  • Since SHBG is produced by the liver, any liver condition—whether it’s fatty liver disease, hepatitis, or cirrhosis—can impact SHBG production. Maintaining liver health is key to ensuring your SHBG levels stay within a healthy range.

Why Testing SHBG is Essential

At Sigma Health, we often look beyond basic hormone tests like free testosterone or estradiol. Understanding your SHBG levels is crucial because they give us a clearer picture of your overall hormone availability. For example, someone may have normal total testosterone levels but still experience symptoms of testosterone deficiency or dominance depending on how much SHBG is present.

Testing SHBG levels can help us:

• Determine true hormone availability: Free hormones are what your body can actually use. SHBG testing ensures we aren’t just looking at the total hormone levels, but at what’s bioavailable.

• Fine-tune bioidentical hormone therapy: If SHBG levels are too high or too low, adjustments to hormone replacement therapy may be needed to optimize treatment.

• Diagnose underlying conditions: Abnormal SHBG levels can indicate underlying metabolic or liver issues that may need to be addressed as part of a comprehensive treatment plan.

How to Balance SHBG Levels Naturally

Balancing SHBG levels is about more than just managing symptoms—it’s about optimizing your overall health. Here are a few ways to naturally support healthy SHBG levels:

• Maintain a Balanced Diet

  • Diets high in sugar and refined carbohydrates can worsen insulin resistance, leading to lower SHBG levels. Focus on a diet rich in healthy fats, lean proteins, and whole grains to support both hormone and metabolic health.

• Exercise Regularly

  • Regular physical activity helps improve insulin sensitivity and can also contribute to optimal SHBG levels, especially in women with PCOS or insulin resistance.

• Support Liver Health

  • A healthy liver is essential for optimal SHBG production. Avoid excessive alcohol consumption, stay hydrated, and incorporate liver-supporting foods like leafy greens, beets, and cruciferous vegetables into your diet.

• Manage Stress

  • Chronic stress can wreak havoc on your hormonal balance, including your SHBG levels. Incorporating stress-reducing activities like meditation, yoga, or breathing exercises can help regulate hormone levels naturally.