A study found that people who maintain a regular daily rhythm tend to show slower biological ageing.

On June 6, online media outlet Gigazine reported that researchers at Johns Hopkins University's Bloomberg School of Public Health confirmed the link by analysing activity and rest rhythm data and ageing biomarkers in the blood of 207 participants with an average age of 68.

The researchers had participants wear a wrist device for 1 week and tracked 24-hour patterns of rest and activity. Rest included not only night sleep and naps but also sitting to read a book or eating meals. The team examined the consistency of rest and activity patterns, the time of day when each pattern was strongest, and differences between rest and active periods.

The researchers then compared epigenetic clocks identified from blood samples with participants' daily rhythms. Epigenetic clocks estimate biological age based on changes in DNA methylation. The analysis showed that participants with more regular daily rhythms tended to have slower biological ageing. By contrast, participants with frequent switches between activity and rest and fragmented rhythms showed faster biological ageing.

The association held even after accounting for factors including actual age, sex, education and certain health conditions. The researchers said the trend was more pronounced in women and white participants.

Co-author Adam Spira (아담 스피라), a professor at Johns Hopkins University's Bloomberg School of Public Health, said rest-activity rhythms could be a useful indicator of the pace of biological ageing in adults. He said that if future research supports the findings, such rhythms could be a potential target for interventions aimed at slowing the ageing process.

The study, however, analysed the relationship between daily rhythms and biological age measured at a single point in time. It did not track participants for weeks to months or longer to confirm how daily rhythms have sustained effects, and it is not yet clear which factors between daily rhythms and biological age influence each other.

Even so, the direction proposed by the researchers aligns with existing research. Earlier studies have suggested that disrupted daily rhythms could be linked to increased inflammation or brain shrinkage, and the latest findings point in the same direction.

Science outlet ScienceAlert noted that maintaining a natural daily rhythm suited to an individual may generally be linked to better health outcomes. It added that follow-up studies tracking participants over the long term are needed to more clearly confirm the relationship between daily rhythms and ageing.

The study showed that managing lifestyle habits may be linked not only to maintaining condition but also to ageing indicators. The researchers said key next steps will be to use long-term tracking to confirm whether a regular daily rhythm actually slows the pace of ageing and in which groups the effect is more pronounced.