Locking in 7–9 hours: the dose–response link between sleep and all‑cause mortality
U.S. men sleeping <7 hours, by age · BRFSS 2022
In 2022, over one‑third of U.S. men reported getting less than 7 hours of sleep, with the highest prevalence in midlife (ages 45–64).
All evidence here is observational (association, not causation), sleep duration is self‑reported, and short sleep often clusters with other risks (shift work, depression, cardiometabolic disease), so “fixing” sleep alone has not yet been shown in large RCTs to normalize mortality risk.
Photo: Pexels.
Large pooled analyses of prospective cohorts show a U‑shaped association between nightly sleep duration and all‑cause mortality, with the lowest risk at roughly 7 hours/night.[8] In a 2022 meta‑analysis of 16 studies including 1.4 million adults followed up to 20 years, sleeping ≤5 hours was linked to about a 15–25% higher all‑cause mortality risk, while ≥9 hours carried a similar excess risk relative to 7 hours.[8] For men 25–55, the key hygiene lever is not a single trick but a consistent schedule that reliably delivers ~7–9 hours of time in bed that tracks this survival “sweet spot.”
Testosterone prescribing keeps climbing — up 45% among men 35–441 from 2018 to 2022 — and in February 2025 the FDA dropped the cardiovascular boxed warning2 from every testosterone product, citing TRAVERSE3 (5,246 men), which found no rise in major cardiac events.
The same document added a new warning that testosterone raises blood pressure2. Then in April 2026, Cambridge researchers used genetics to test cause, not correlation4, and found men with naturally higher lifelong testosterone carried about 17% more coronary artery disease. There was no effect in women.
Read together, the trials describe something narrower than the ads: testosterone looks reasonably safe for men who genuinely need it and get monitored, the benefit is real but bounded, and the heart question now runs through blood pressure. Tomorrow we look at whether a higher number actually changes how men feel.
- +45%2018–2022 · US Pharmacist
Rise in testosterone prescriptions among U.S. men 35–44.
- 50%6 pts vs women · CDC
U.S. men with high blood pressure — the risk the new label flags.
- 16%per 5 kg grip · Lancet · PURE
More all-cause death risk as grip strength falls.
- 15%sleep ≤5h · HarvardSleep
Pooled cohort analysis: men sleeping ≤5 hours a night carried up to 15% higher all-cause mortality risk than longer sleepers.[9]
Every week a man emails asking how to raise his testosterone. Almost no one asks the question underneath it: do I actually have low testosterone, or do I just feel worse than I did at 30?
They're different problems. Hypogonadism is a diagnosis5 — low morning testosterone on two draws, plus symptoms. Feeling flat, sleeping badly, soft around the middle is not that. It's also the picture that improves most with training and sleep.
This week's data doesn't say testosterone is dangerous. It says it raises blood pressure, and the heart cares about lifelong exposure. So before chasing a number up, the free wins come first: lift, walk, and own a cuff.
— The MD
A 2024 meta-analysis6 found creatine's effect on thinking is small and mostly limited to memory under stress — the muscle case is far stronger than the brain case.
Each 1-MET of cardio fitness is associated with roughly 13% lower all-cause mortality7 — an association, not proof, but among the most replicated findings in the literature.
Up to ~40% of the weight people lose on semaglutide is lean mass, not fat, per the ADA8; pairing the drug with protein and lifting shifts that back toward fat.
- StrongLifts 5×5 — the stripped-down barbell program a generation of lifters started on: five lifts, three days a week.
- Trolltunga — a slab of rock jutting 2,300 feet over a Norwegian fjord; the 17-mile round trip has quietly become a pilgrimage.
- r/Testosterone — where men post their bloodwork, their dosing, and "don't let them lower my dose." The optimizer subculture, unfiltered.
- Pact — an organic-cotton basics brand that's quietly won over the boring-essentials crowd.
- Singer's reimagined 911 — the restomod that turns a 1990s Porsche into a seven-figure object of obsession.
Some links may be affiliate links. We only list things we'd actually use.
A man lives on the 10th floor. Every morning he takes the elevator to the ground and goes to work. Coming home, he rides to the 7th floor and walks the rest — except on rainy days, when he rides all the way to the 10th. Why?
The answer drops in the next issue.
Ultracrepidarian — (n.) someone who gives opinions on subjects beyond their knowledge. Useful this week.
Did you know
Cleopatra lived closer in time to the Moon landing than to the building of the Great Pyramid9. The pyramid was already ~2,500 years old in her lifetime; she died only ~2,000 years before Apollo 11.
Health reporting, never medical advice.
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