Sleep Duration Outperforms Diet and Exercise as a Predictor of Longevity in New US Study

Key points

• Researchers at Oregon Health & Science University analyzed county-level survey data from the US between 2019 and 2025 to compare life expectancy with self-reported sleep duration.
• The study defined insufficient sleep as less than seven hours per night and found it to be a stronger predictor of lower life expectancy than diet or exercise.
• In the initial model, only smoking had a stronger association with life expectancy than insufficient sleep; in a second model including obesity and diabetes, obesity also ranked higher.
• The association between insufficient sleep and lower life expectancy remained statistically significant after controlling for physical inactivity, employment status, and educational level.
• Lead researcher Andrew McHill noted that while the observational nature of the study prevents causal claims, the strength of the correlation was 'remarkable' and suggests sleep should be prioritized alongside diet and exercise.
• The American Academy of Sleep Medicine and the Sleep Research Society recommend at least seven hours of sleep per night, with some evidence suggesting weekend catch-up may help.

Background

This finding aligns with earlier coverage from our archive, which highlighted sleep as a foundational pillar of longevity alongside diet, exercise, and stress management. In August 2026, geriatric experts listed adequate sleep among eight key habits for healthy aging, while a September 2026 article on epigenetic clocks noted that well-established habits, including sufficient sleep, have the strongest evidence for supporting healthspan. These prior reports emphasized that while specific interventions like Mediterranean diets or certain drugs may slow epigenetic aging, basic lifestyle factors remain the most reliable predictors of long-term health outcomes.

Why it matters

The study underscores that sleep is not merely a restorative activity but a critical, modifiable determinant of lifespan. By demonstrating that sleep duration correlates more strongly with life expectancy than diet or exercise, the research challenges the common hierarchy of health priorities. This suggests that public health strategies and individual wellness routines should place greater emphasis on achieving seven to nine hours of sleep, as poor sleep is linked to conditions like obesity and diabetes that directly reduce life expectancy. While the study cannot prove causation, the robust association highlights the need to address sleep deprivation as a primary factor in longevity discussions.

What to watch

Researchers will likely continue to investigate the mechanisms linking sleep duration to mortality, particularly how poor sleep contributes to obesity and diabetes. Public health organizations may update guidelines to emphasize sleep as a primary longevity factor, alongside diet and exercise. Individuals may adopt better sleep hygiene practices, such as reducing screen time before bed or incorporating relaxation techniques, to meet the recommended seven-hour minimum. Further studies may explore whether weekend catch-up sleep can mitigate the effects of weekday sleep deprivation, as hinted at by current evidence.