During the summer break from school, it’s not unusual to hear parents complain that their teenage kids are sleeping until noon or later every single day. Yet given the same opportunity, older adults often go to bed early and wake up early. The question is: why is there a difference?
The biggest difference is that the circadian rhythm is naturally different for teens than it is for older adults. These rhythms can be impacted by the hormonal changes going on in a teenager, but it’s a lot more complex than that and it can’t be described as simply being related to age.
What is the circadian rhythm?
The circadian rhythm is the natural cycle of sleeping, waking and eating during a 24 hour period. This internal body or biological clock is responsible for the times you feel alert, sleepy or hungry. It is different for each person, but there are some generalizations we can draw:
- Preschool aged children not only sleep at night, but often need naps during the day. They usually get hungry between meals and often require snacks.
- Teenagers often go to sleep very late and wake up very late. If left to make their own schedule, they usually won’t eat three meals per day. Although they can eat a lot, they often eat sporadically and may only get one primary meal per day and will snack in between.
- As teenagers turn into adults, they start to go to bed earlier and wake up earlier. Adults also tend to start eating at regular schedules during the day again as they wake up hungry, need a mid-day meal and then one several hours before bedtime. However, they may start to eat less during meals.
Disrupting your body clock
What you eat, how much you eat and when you eat can disrupt your body clock and cause you to feel stressed and overtired during the day. One Vanderbilt study shows that not eating on your body’s schedule can lead to higher rates of obesity and a higher risk of diabetes and heart disease. This is why people who work swing shifts, rotating schedules or overnight shifts have a higher risk of chronic diseases than those who work during sunlight hours.
Make it work for you
Most circadian rhythms provide an eight-hour span where a person feels most active and energetic. In studies that compare mice that could only eat during their peak energy times against mice that could eat around the clock, those that ate only during peak energy times “were 40% leaner and had lower cholesterol and blood sugar”.
This means you should also eat during your peak energy times. For most adults, this is between 11 am and 7 pm at night. If you eat outside of your peak energy times, you may disrupt your natural body rhythm, which in turn will cause problems for you. It can disrupt your sleep cycles and may make you feel less energetic overall.
Furthermore, It is thought that if you have to consume most of your daily diet either at the beginning of your peak activity time or at the end of your peak activity time. In fact, you are much better off opting for the earlier time. The popular theory is that the earlier time allows your body to process food during your peak times as well.