Most Adults Need About 7–9 Hours; CVD Risk Is U-Shaped
Key takeaway
Most adults should aim for about 7–9 hours (at least 7). Some CVD studies show a risk nadir near ~7 hours, but that is not the same as “exactly 7 hours only.”
- Aim for at least 7 hours; many adults do best in a 7–9 hour band.
- Habitual short sleep tracks with higher CVD risk in populations.
| Guidance | Scientific Observation | Impact Magnitude | ||
|---|---|---|---|---|
| ≥7 h / ~7–9 h | AASM adult duration consensus | Recommended range | ||
| ≤6 h | Associated with higher CVD risk | Elevated relative risk | ||
| ≥9 h | Also elevated in U-shaped analyses | Not “more is always better” |