(NaturalHealth365)  Most people rank diet and exercise at the top of their longevity priorities.  A major new study suggests that ranking may be wrong – and that the health habit most Americans are quietly neglecting may be doing more damage than both combined.

Researchers at Oregon Health & Science University analyzed CDC survey data spanning 2019 to 2025 across more than 3,000 US counties, comparing sleep sufficiency rates with county-level life expectancy.  After controlling for smoking, diet, physical inactivity, obesity, and loneliness, one finding stood out sharply.  Sleep insufficiency ranked as the second-strongest predictor of shorter life expectancy – surpassed only by smoking and stronger than any dietary or exercise factor the researchers examined.  The correlation held in all but three US states, year after year, across the entire six-year study period.

Sleep outperformed diet and exercise as a longevity predictor – and that surprised even the researchers

The study’s senior author, Andrew McHill, Ph.D., associate professor at OHSU’s School of Nursing and Medicine, did not expect the finding to be this definitive.  The threshold was straightforward: fewer than seven hours of sleep per night constituted insufficient sleep, consistent with national sleep guidelines.

Counties where more residents regularly fell below that threshold had consistently shorter life expectancies – and the relationship held regardless of income level, healthcare access, or whether the county was urban or rural.  Neighboring counties sometimes showed gaps of 15 percentage points or more in sleep sufficiency rates, with corresponding gaps in life expectancy spanning several years.

Meanwhile, the National Sleep Foundation’s 2025 Sleep in America poll confirmed that 60% of American adults are not getting enough sleep.  The scale of the problem and the strength of its association with shortened lifespan make this one of the most significant public health findings published this year.

Why sleep deprivation shortens life — the mechanisms most people are never told about

The biological consequences of chronic insufficient sleep extend far beyond feeling tired.  Sleep is the period during which the body performs its most critical repair and detoxification work, and consistently cutting that window short creates a compounding deficit that affects nearly every major system.

The brain’s glymphatic system – the network responsible for clearing metabolic waste and toxic proteins from neural tissue – operates almost exclusively during sleep.  Chronic sleep deprivation means that cellular waste, including proteins linked to neurodegenerative disease, accumulates in brain tissue instead of being cleared.  The liver, the body’s primary detoxification organ, follows circadian rhythms that depend on consistent, sufficient sleep to regulate enzyme activity and process the toxic burden accumulated during waking hours.

Poor sleep disrupts that cycle and impairs the liver’s ability to efficiently clear environmental chemicals, hormones, and metabolic byproducts.

Beyond detoxification, insufficient sleep chronically elevates cortisol and inflammatory markers, impairs insulin sensitivity, suppresses immune surveillance, and disrupts the hormonal signaling that governs cellular repair.  Each of these mechanisms independently raises the risk of cardiovascular disease, metabolic dysfunction, and cancer, which helps explain why the OHSU study found sleep to be such a powerful predictor of overall life expectancy rather than of any single disease.

What consistently good sleep requires

The research is clear: the target is seven to nine hours per night, consistently, not just on weekends.  Weekend catch-up sleep does not fully offset the deficit accumulated during the week, and irregular sleep timing disrupts circadian rhythms in ways that carry their own health consequences.

Several evidence-based practices consistently support sleep quality.  Keeping sleep and wake times consistent, even on weekends, stabilizes the circadian system.  Avoiding screens for at least 90 minutes before bed limits blue light exposure, which suppresses melatonin production.

Keeping the sleeping environment cool, dark, and free from electronics reduces cortisol and supports deeper sleep architecture.  Avoiding caffeine after early afternoon prevents the adenosine interference that fragments sleep in the second half of the night.

Addressing the root causes of poor sleep matters equally.  Chronic stress, toxic burden, blood sugar dysregulation, and nutrient deficiencies – particularly magnesium and B vitamins – are among the most common drivers of sleep difficulty that Western medicine rarely investigates in a standard appointment.

Poor sleep and toxic accumulation also reinforce each other: the body struggles to detoxify when sleep-deprived, and accumulated toxins further disrupt sleep quality, creating a cycle that compounds over time.

Breaking that cycle requires addressing both sides simultaneously.  The body’s detoxification systems and sleep architecture are more tightly connected than most people realize, and understanding how to support both is exactly the territory that most standard medical care leaves unexplored.

That is where Jonathan Landsman’s Whole Body Detox Summit can help you discover the best strategies for detoxification.

Twenty-seven leading holistic doctors and natural healthcare experts examine the toxic load most people unknowingly carry – the environmental chemicals, dietary exposures, and internal waste accumulation that impair sleep, accelerate aging, and quietly drive chronic disease.  If sleep is where the body heals, learning what is blocking that healing is where recovery actually begins.

Sources for this article include:

Academic.oup.com
Ohsu.edu
Neurosciencenews.com