AI Insight
Researchers conducted a comprehensive quantitative analysis of circulating hormones in human blood, finding that the total mass of all hormones combined is approximately 40 mg, with two hormones (Adiponectin and DHEAS) comprising over 90% of this mass and total copy number. The study analyzed 56 hormones using clinically validated reference intervals and found that humans have roughly one million hormone molecules per cell, with females having about half the total number of circulating hormone molecules compared to males. The analysis also revealed that free hormone concentrations correlate with receptor binding affinity in a class-specific manner, and bioavailability mechanisms differ by chemical class.
Why it matters
This work provides the first systematic quantitative reference for the human endocrine system, offering essential baseline data for understanding hormonal health, diagnosing endocrine disorders, and developing targeted therapies. The findings about sex differences and hormone-receptor binding relationships could inform personalized medicine approaches and improve treatment strategies for hormonal imbalances.
Understand the Science
by Ron Sender, Tal Kedar, Yoav Navon, Moriya Raz, Shirley Bikel, Rina Hemi, Ron Milo, Shai Fuchs
The human endocrine system orchestrates critical physiological processes, yet a systematic quantitative synthesis of clinically relevant circulating hormones has been lacking. Here, we present a comprehensive, integrative analysis of circulating human hormones, leveraging clinically validated reference intervals across major endocrine subsystems. We use clinically validated reference intervals that we further validate using published datasets. Our analysis reveals that the total mass of circulating hormones is approximately 40 ± 2 mg. We find that this mass in healthy young adults is dominated by Adiponectin and DHEAS, which constitute over 90% of both total hormone weight and copy number. We show there are on the order of a million hormone molecules per cell in the human body. Females have about half the number of circulating hormone molecules compared to males. Across 56 hormones with curated affinity data, free (receptor-available) concentration correlates with receptor binding affinity, with class-specific scaling. Bioavailability mechanisms segregate by chemical class, consistent with chemical structure constraining available buffering strategies. Together, these data provide a quantitative reference for the human endocrine system and highlight relationships linking receptor affinity, bioavailability, and chemical class.
Source: The total mass, copy number, and distribution of hormones in the human bloodstream