Hormone Science

Estrogen Is Not Just a Female Hormone: Where It Comes From and What It Does
Estrogen Is Not Just a Female Hormone: Where It Comes From and What It Does
Day 2 of our hormone series: how your body makes estrogen, why men need it too, and what the largest long-term trials say about hormone therapy. Read more...
Testosterone 101: What It Does and What Your Number Really Means
Testosterone 101: What It Does and What Your Number Really Means
Day 1 of our hormone series: what testosterone does, why the same number can mean different things, and what the latest research says about low levels. Read more...
Glucose Is Insulin's Shadow: What Consumer Glucose Sensors Can (and Can't) Tell You Without Diabetes
Glucose Is Insulin's Shadow: What Consumer Glucose Sensors Can (and Can't) Tell You Without Diabetes
Over-the-counter sensors let anyone watch their glucose. A 2026 meta-analysis and a new preprint show what that may reveal about insulin, and where the evidence stops. Read more...
Melatonin Is a Hormone, Not a Vitamin
Melatonin Is a Hormone, Not a Vitamin
A heart-failure signal, a dosing puzzle and unreliable labels: how to think about nightly melatonin in 2026. Read more...
Your Heart-Rate Variability Moves With Your Cycle. Your Wearable Should Know That.
Your Heart-Rate Variability Moves With Your Cycle. Your Wearable Should Know That.
What a 2026 living systematic review says about HRV, the menstrual cycle, contraceptives and midlife, and why a single "readiness score" can mislead. Read more...
Do GLP-1 Drugs Raise Testosterone? What the Evidence Says So Far
Do GLP-1 Drugs Raise Testosterone? What the Evidence Says So Far
In men with obesity, weight-loss drugs may lift low testosterone — but the data are small, short, and mostly indirect. Read more...
A Slightly High TSH: Does Treating It Actually Help?
A Slightly High TSH: Does Treating It Actually Help?
Subclinical hypothyroidism is one of the most common abnormal results in medicine. For older adults, the best evidence says treatment often adds little. Read more...
One Short Night, Many Hormones: What Sleep Loss Really Does to Your Endocrine System
One Short Night, Many Hormones: What Sleep Loss Really Does to Your Endocrine System
Headlines promise dramatic hormone crashes after a bad night. The best available evidence is more nuanced, and more interesting. Read more...
Menopause hormone therapy in 2026
Menopause Hormone Therapy in 2026: What the New Label and the New Dementia Data Actually Say
The FDA softened its boxed warnings, and a million-woman meta-analysis finds no dementia signal either way. Read more...
Testosterone therapy after TRAVERSE
Testosterone Therapy After TRAVERSE: What the Heart-Safety Data Does and Doesn't Say
The FDA dropped the cardiovascular boxed warning in 2025 but added a blood pressure warning. Here is how to read both changes together. Read more...