Hormone Health Hub: Expert Insights on Testing, Balance & Better Living — sex hormone

Dr David Zava of ZRT Laboratory explores how topical bioidentical hormone therapy (BHRT) distributes differently across body fluids — and why saliva and dried blood spot testing offer a more accurate picture of tissue hormone levels than serum or urine.

By Dr. Allison Smith, ZRT Laboratory Sex Hormone Binding Globulin (SHBG) is one of the most overlooked variables in hormone health. It directly controls how much testosterone is biologically active in your body — yet it rarely appears on standard blood panels. Whether you're dealing with symptoms of low testosterone, androgen excess, or unexplained hormonal imbalance, understanding SHBG is essential to getting the full picture. What is SHBG? SHBG is a protein produced primarily in the liver that binds tightly to testosterone — and to a lesser degree, oestradiol (E2) and dihydrotestosterone (DHT) — and carries them through the bloodstream....