[Health Channel/Comprehensive Report] Nutritionist Xue Xiaojing said on the Facebook fan page "Nutritionist Mom Xiaojing's Life Notes" that although they are both 68 years old, why do some people seem to be in good spirits while others are always tired? The latest research in 2026 reminds: In addition to how long you sleep, "whether you have a fixed daily rhythm of life" may also be related to body aging!
Xue Xiaojing said that when it comes to anti-aging, the first thing some people think of is a healthy diet, regular exercise, and sleeping for 7 or 8 hours a day. But if you go to bed at 11 o'clock today, you won't go to bed until 2 o'clock tomorrow morning; you get up at 7 o'clock in the morning on weekdays, but sleep until noon on weekends; you sit all day during the day, but you feel very energetic at night and start watching TV series and scrolling on your mobile phone. Even if the "total sleep hours" appear to be similar, the activity and rest signals the body receives every day may be completely different.
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Lifestyle: Aging slowly
A study published in "JAMA Network Open" in May 2026 looks at "aging" from another perspective: the more obvious and regular the 24-hour rest-activity rhythm of middle-aged and elderly people is, the more regular it is every day, which is related to slower epigenetic aging; conversely, the more fragmented the life rhythm, and the daily sleep and rest time changes, is related to faster epigenetic aging.
Anti-aging is not just about "sleeping an extra hour tonight", the daily rhythm may also be important. Xue Xiaojing cited a study that included 207 elderly adults in the American community, with an average age of 68.4 years old, about 65% of whom were women. The researchers did not just rely on questionnaires to ask "how long they usually sleep." Instead, they asked participants to wear wrist actigraphs continuously, and obtained effective data for an average of about 5.8 days. They watch 24 hours:
● Is the difference between daytime activities and nighttime rest obvious enough?
● Do you generally follow a fixed time schedule every day?
● Is your activity level still high during the period when you should be resting?
● Do you frequently switch between activities and rest throughout the day?
At the same time, the research team drew blood to analyze DNA methylation, and used four "epigenetic clocks": GrimAge, PhenoAge, Horvath and Hannum to observe related indicators of biological aging. The most noteworthy result of the study was not the finding of an "optimal time to fall asleep." On the contrary, "life is irregular."
Research has found that the more obvious the "amplitude" of the 24-hour activity rhythm, that is, the clearer the difference between daytime and nighttime activities, is related to lower GrimAge and PhenoAge acceleration. To put it simply: I really get up and move during the day, and gradually calm down at night. This is more consistent with a clear rest-activity rhythm than having the same amount of activity throughout the day.
In addition, maintaining similar activity patterns at similar times every day, which is the "interdaily stability" in the study, is also related to lower GrimAge and PhenoAge acceleration. Conversely, if activity and rest are often fragmented throughout the day, higher intradaily variability in the study is associated with higher GrimAge acceleration.
Xue Xiaojing reminded that if you go to bed very early today and go to bed very late tomorrow, the midpoint of rest and sleep time changes greatly every day, which is also related to higher PhenoAge acceleration. In other words, the body seems to not only care about "how many hours of sleep today", but also whether the rhythm of life yesterday, today and tomorrow is similar.
Why might "the rhythm of life" be related to aging?
Xue Xiaojing said that the human body’s day and night rhythm is never only responsible for making people want to sleep at night. Blood sugar regulation, insulin sensitivity, hormones, immune response, mitochondrial function, oxidative stress, and DNA repair all vary to varying degrees day and night.
Researchers believe that a stronger and more regular rest-activity rhythm may help maintain metabolic stability and mitochondrial function, and may also be related to lower oxidative stress. Conversely, long-term dysrhythmias may implicate chronic low-grade inflammation, oxidative stress, and repair functions during sleep.
Xue Xiaojing said that this is actually very common in mature life. After retirement, you don’t have to rush to work and wake up later and later in the morning. You can sit or lie down during the day if you have nothing to do, and then sleep for an hour or two in the afternoon. Naturally, you won’t be too sleepy at night. So what time do you get up every day, when do you go out for a walk, and when do you eat? These seemingly ordinary life arrangements actually help the body establish a relatively stable 24-hour rhythm.
However, this study cannot be directly interpreted as "a regular routine can make DNA younger." This is a cross-sectional study, which can only see the relationship between "rest-activity rhythm" and "epigenetic aging", but cannot prove who causes whom. It may also be that people who are in better physical condition and have relatively complete mobility functions are naturally easier to maintain a regular life.
In addition, the study only included 207 people, with activity records lasting about a week, and they were mainly from the Baltimore area in the United States. Long-term studies with larger and more diverse groups are still needed in the future. Another important point: this study does not prove that going to bed earlier is better. The results of research on "the best time to sleep and what time to exercise" are actually inconsistent and will be affected by age. Therefore, the results cannot be simplified to: people who go to bed late must age faster, people who go to bed early must be younger, and everyone must go to bed before 10 pm.
Experts recommend 5 things to adjust your life rhythm
At present, the more consistent view is that there is a clear difference between day and night, and daily life is relatively regular. If you want to help yourself or the elders in your family regain the pace of life, you can do these 5 things first
● Fix the time to get up first: Instead of lying in bed and forcing yourself to "go to bed at 10 o'clock today", it is better to start in the morning.
Try not to have too much difference in wake-up time on weekdays and holidays, so that light, breakfast, activities and sleepiness at night gradually form a fixed rhythm.
● You really need to "light up and move" during the day: get in touch with natural light after getting up, and arrange grocery shopping, walking, housework or exercise during the day.
If you don't sleep well at night and keep lying down to catch up on sleep during the day, it is easy for the difference between day and night activities to become smaller and smaller.
●You don’t need to go for a run at the beginning: walk for 10 to 15 minutes after meals, and arrange an activity in the morning and afternoon, which is easier for many elders to do.
●Don’t have three or four hours difference between meals every day: breakfast at 8 o’clock today, 11 o’clock tomorrow; dinner sometimes at 6 o’clock, sometimes at 10 o’clock, plus a late night snack, the time signal your metabolism receives every day will also change accordingly.
It is not necessary to be precise enough to eat breakfast at a fixed time every day, but the three meals should be roughly maintained at a fixed time period, and try not to delay eating dinner until before going to bed.
●Sufficient protein is required to maintain daytime activity: Mature people have less daytime activity, which is often accompanied by muscle loss. After muscle strength declines, you will walk less and get tired easily, and your activity level will further decrease.
Each meal can be about a palm-sized portion of fish, eggs, tofu, meat, or paired with dairy products so that the muscles have enough repair materials.
●Let the body slowly enter the "rest period" at night: A large amount of caffeine in the afternoon and evening, drinking alcohol to help fall asleep, or eating a large meal before going to bed may make some people's sleep more fragmented.
●People who are prone to sleep instability can choose one adjustment at a time: reduce caffeine after the afternoon, use alcohol to help sleep, move snacks to a later date, and reduce long scrolling on mobile phones before going to bed. You don’t have to do them all at once, just find the one that most easily disturbs you and change it first.
Healthy mature life is simple
Xue Xiaojing concluded that "being healthy at a mature age" is not just about doing more things every day, but also about having "activity when you should be active and taking a good rest when you should rest." What this study is really worth bringing back to life is to re-examine your 24 hours: Do you get up at the same time every day in the morning? Are there any real activities during the day? Is there a basic rhythm to three meals? At night, does life slowly calm down?
Getting up regularly, doing activities during the day, eating normally, and resting at night are actually a set of connected life rhythms. There is no need to pursue a "perfect routine"; getting up at a fixed time tomorrow morning, going out to get some sunshine, and walking for 10 minutes is a good start.
