Sleep duration and quality

stress neuroendocrineinflammation redox

Not a regulated product. No approval pathway exists for this intervention in any market, and none is required to practise it.

Evidence so far is from observational studies in people. 6 other studies gave a different intervention (24-form Tai Chi; Aerobic training versus resistance…; Mild sleep restriction; …) and are shown for context, not counted.

Evidence map

each mark is a study; size shows participants; hover, tap or focus for details

main endpoints improvedno effectworsenedmixedobservationalanother intervention, contextsize not reported

Higher rows are closer to a person taking this. A case that rests only on the lower rows rests on animals or cells.

What each study measured

outlined square: the main (primary) endpoint

Harms reported

human studies

Where it is available

by regulator; select a market for its source

If you are tracking this yourself

measures the human studies used, by how repeatable they are

Repeatability is whether the same person measured twice gets the same number. It is not statistical significance. It informs study or protocol design only, never advice for a person.

What would change this picture

each study's own statement

Trials under way

Every study (11)

T7 Irwin 2008 Improving Sleep Quality in Older Adults with Moderate Sleep Complaints: A Randomized Controlled Trial of Tai Chi Chih doi:10.5665/sleep/31.7.1001
T7 Lyu 2026 Tai Chi exercise improves sleep quality in older adults with mild insomnia by enhancing slow-wave activity during deep sleep: a 12-week randomized controlled trial doi:10.3389/fphys.2026.1795646
T7 Tseng 2020 Effects of exercise training on sleep quality and heart rate variability in middle-aged and older adults with poor sleep quality: a randomized controlled trial doi:10.5664/jcsm.8560
T7 Gupta 2022 A clinical trial to compare the effects of aerobic training and resistance training on sleep quality and quality of life in older adults with sleep disturbance doi:10.5935/1984-0063.20220040
T6 Barragán 2026 Prolonged Mild Sleep Restriction Changes Epigenome-Wide DNA Methylation in Peripheral Blood Cells: A Randomized Crossover Trial doi:10.14336/AD.2025.1261
T5 Ke 2025 Association Between Abnormal Sleep and Mortality Risk: A Nationwide Prospective Cohort Study of All-Cause and Cardiovascular disease Mortality doi:10.1101/2025.02.21.25322660
T5 Ren 2026 Nighttime sleep, midday napping, and mortality in Chinese older adults: A China Health and Retirement Longitudinal Study longitudinal cohort study doi:10.1177/03000605261467619
T5 Liu 2026 Sleep habits and incident physical, psychological, and cognitive multimorbidity: a longitudinal cohort study doi:10.1016/j.jnha.2026.100957
T5 Xiao 2017 Prediagnosis Sleep Duration, Napping, and Mortality Among Colorectal Cancer Survivors in a Large US Cohort doi:10.1093/sleep/zsx010
T5 Young 2008 Sleep Disordered Breathing and Mortality: Eighteen-Year Follow-up of the Wisconsin Sleep Cohort doi:10.5665/sleep/31.8.1071
TX Jones 2011 Insomnia with Short Sleep Duration and Mortality: The Penn State Cohort doi:10.1016/j.ypdi.2010.12.033