Why Sleep is the #1 Health Habit - 1/27/2026
Share
Getting enough sleep is the easiest way to improve your health—but why is it so powerful? This page provides the research sources and citations for claims made in our video about sleep and health.
Sources
Sleep as a Predictor of Life Expectancy
"As a behavioral driver for life expectancy, sleep stood out more than diet, more than exercise, more than loneliness — indeed, more than any other factor except smoking."
McHill, A. et al. (2025). "Insufficient sleep associated with decreased life expectancy." SLEEP Advances. Oregon Health & Science University.
Available: https://news.ohsu.edu/2025/12/08/insufficient-sleep-associated-with-decreased-life-expectancy
Sleep Deprivation Linked to Leading Causes of Death
"In the United States, sleep deprivation has been linked to 5 of the top 15 leading causes of death including cardio- and cerebrovascular diseases, accidents, type 2 diabetes, and hypertension."
Garbarino, S. et al. (2021). "Role of sleep deprivation in immune-related disease risk and outcomes." Communications Biology, Nature.
Available: https://www.nature.com/articles/s42003-021-02825-4
Obesity Risk
"Sleep deprivation increases the risk for obesity by about 55%."
Garbarino, S. et al. (2021). "Role of sleep deprivation in immune-related disease risk and outcomes." Communications Biology, Nature.
Available: https://pmc.ncbi.nlm.nih.gov/articles/PMC8602722/
Type 2 Diabetes Risk
"Sleep deprivation carries a 28% higher risk of type 2 diabetes."
Garbarino, S. et al. (2021). "Role of sleep deprivation in immune-related disease risk and outcomes." Communications Biology, Nature.
Available: https://pmc.ncbi.nlm.nih.gov/articles/PMC8602722/
Depression and Mental Health
"Half of all adults and over 40% of teens who reported sleeping less than NSF recommended levels per weekday night also reported mild or greater levels of depressive symptoms."
National Sleep Foundation. (2024). "Sleep Health and Mental Health: A Position Statement."
What Happens During Sleep (Repair and Prepare Mode)
"Sleep profoundly affects endocrine, metabolic, and immune pathways... Regular sleep is crucial for maintaining immune function integrity and favoring a homeostatic immune defense to microbial or inflammatory insults."
Garbarino, S. et al. (2021). "Role of sleep deprivation in immune-related disease risk and outcomes." Communications Biology, Nature.
Available: https://www.nature.com/articles/s42003-021-02825-4
Additional Supporting Research
Cardiovascular Disease Risk: "Sleep deprivation (commonly less than 7 hours per night) is associated with a 48% higher risk of coronary heart disease, a 15% higher risk of stroke, and a 12% increased risk of all-cause mortality."
Available: https://pmc.ncbi.nlm.nih.gov/articles/PMC8602722/
Recommended Sleep Duration: "Adults should sleep at least 7 hours a night on a regular basis to promote optimal health."
American Academy of Sleep Medicine and Sleep Research Society.
Available: https://datastories.aarp.org/2024/quality-sleep/
Sleep and Flourishing: "72% of people with good sleep health were flourishing, compared to 46% of people with poor sleep health."
National Sleep Foundation. (2025). "Sleep in America Poll."
Available: https://www.thensf.org/wp-content/uploads/2025/03/NSF_SIA_2025-Report_final.pdf
Video Script Summary
Getting enough sleep is the easiest way to improve your health, but why is it?
A 2025 study showed that sufficient sleep was a stronger independent predictor for life expectancy than diet and exercise, and the only unhealthy habit that trumped it was smoking.
Another study showed that 5 out of 15 leading causes of death in the United States are correlated with quality of sleep.
Sleep deprivation has also been shown to increase chance of obesity by 55%, a 28% higher chance of type 2 diabetes, and increases likelihood for depression.
So why is sleep so effective? Every night when you go to bed your body enters repair and prepare mode.
During sleep, your body repairs tissue, regulates hormones, clears metabolic waste from the brain, and resets systems that control appetite, mood, and immunity.
So listen to your body and go to bed instead of more doomscrolling.