A recent study published in The Journal of Pediatrics found that children who get less sleep may experience cellular aging at a faster rate than children who get more sleep.
The cells in our body carry around chromosomes, which contain our DNA. Over time, our cells divide. Cells divide in order for us to grow, as well as to replace old or damaged cells, like when we get a cut. When cells divide, all of the chromosomes are copied and distributed to the new cells. The longer we live, the more cycles of cell division we experience. When the cells divide and chromosomes replicate, there are little caps on the ends of the chromosomes that protect our DNA. These little caps are called telomeres. However, with each cycle of cell division, the telomeres get shorter. Eventually, telomeres get short enough where they can no longer protect the chromosomes from getting damaged during cell division. When this happens, a cell can no longer divide and reproduce, and the cell dies. You can think of telomeres as the plastic on the end of a shoelace. When the plastic wears off, the shoelace frays, and can no longer fit through the shoelace eyelet. Cell division and telomere shortening is a part of the natural aging process for a cell.
This study found that telomere shortening happens faster with poor sleep. Researchers compared telomere length and average nightly sleep duration in over 1500 nine year olds. Researchers measured telomere length by using DNA from saliva samples. Sleep duration, reported by each child’s mother, ranged from 6 hours to 12 hours per night. The results revealed that with each decreasing hour of sleep, there was a decrease in telomere length. In this study, race, sex, or socioeconomic status did not appear to influence the relationship between sleep duration and telomere length. This is the first study to show a relationship between sleep duration and telomere length in children, although other research has revealed a similar relationship in adults.
However, these findings are observational. This means that it is unclear if a decrease in sleep duration leads to telomere shortening or if telomere length is related to some other factor(s) that may explain short sleep duration and telomere length. Additionally, because this study used parental sleep report, sleep duration may not be completely accurate.