A new study explores how consistent sleep routines not just hours could shape your longterm health
-
A large study of 88,461 UK adults linked six objective sleep traits including bedtime regularity with 172 diseases.
-
Sleeptiming consistency and rhythm stability had stronger ties to disease risk than just sleep duration.
-
Irregular bedtimes doubled or tripled risk for certain conditions like liver cirrhosis and gangrene.
Most of us think of good sleep as simply getting enough hours every night.
However, recent research flips that idea on its head: its not only how long you sleep but when and how regularly.
An international analysis used real, measurable sleep data to uncover surprising links between sleep patterns and a wide range of diseases bringing bedtime consistency into the health spotlight.
Our findings underscore the overlooked importance of sleep regularity, researcher Prof. Shengfeng Wang said in a news release. Its time we broaden our definition of good sleep beyond just duration.
The study
For the study, researchers tapped into data from the U.K. Biobank. More than 88,000 adults wore wrist-based trackers for an average of 6.8 years.
This allowed objective measurement of six sleep traits: total sleep duration, sleep timing (bedtime), relative amplitude, interdaily stability (consistency day-to-day), sleep efficiency, and number of times waking up.
They then ran a phenomewide association study, which means they analyzed links between those sleep traits and hundreds of diagnoses across body systems. That way, rather than guessing, they looked at real-world health outcomes tied to actual behavior.
The results
The headline finding: 172 diseases showed statistically significant associations with at least one sleep trait. For many, sleep patterns accounted for an average of 23% of risk burden in that category.
Irregular bedtimes after 12:30a.m. doubled the odds of liver cirrhosis (2.57), while unstable day-to-day sleep rhythm increased gangrene risk by about 2.6.
Interestingly, the old warning about long sleep ( nine hours) being bad for you didnt hold up under objective scrutiny. Many people who reported long sleep were actually sleeping less than six hours meaning time in bed was often mistaken for rest.
The researchers suggest that these findings are biologically plausible irregular sleep may disrupt circadian rhythms and inflammation pathways. They also replicated key associations in U.S. cohorts, reinforcing generalizability.
Posted: 2025-07-29 18:11:24