Does being a night owl have health consequences, regardless of how many hours of sleep you get? It certainly appears so, according to recently published research. It seems the early bird not only gets the worm, as the saying goes, it also benefits from better health.
People with what is known as evening chronotype — that is, a pattern of staying up and waking later in the day — have more than four times the risk of cardiovascular disease and six times the risk of type 2 diabetes than so-called early birds, those who greet the dawn with energy and enthusiasm. In fact, even people who start their day a little later, known as intermediate chronotype, are far healthier that those who burn the midnight oil, the study found.
Why It Matters
It’s not just a question of lifestyle, says Harneet Walia, M.D., medical director of sleep medicine at Miami Cardiac & Vascular Institute. People with evening chronotype experience disruptions to their body clock, known as circadian rhythm, as their bodies rebel against a 9-to-5 world. This can profoundly affect overall health.
“There is emerging research about circadian rhythms,” Dr. Walia says. “The time we go to bed and wake up can have a lot of implications, probably because there is a misalignment between your external clock and your internal clock.”
Conducted at the University Federico II in Italy and reported at the European Congress on Obesity, the study quantified the health risks by looking at 172 middle-aged adults and adjusting the analysis for age, gender, body mass and sleep quality. It found adhering to an evening chronotype can alter metabolic processes due to over-activation of the hypothalamus-pituitary-adrenal axis, a collection of linked body systems that control our reaction to stress, digestion, the immune system and various other functions.
In other words, Dr. Walia says, “If you consistently stay up too late, you’ll be out of sync with the natural world.”
All tissues in the human body contain molecular clocks that coordinate our biological systems, influencing blood sugar, appetite, heart rates, body temperature, gene expression, cell division, energy expenditure and other processes. The workings of these internal clocks are not fully understood, but they are driven by complex cues from inside and outside of our bodies. Most notably, they synchronize to light and darkness.
Addressing the Problem
If you have concerns about your ability to fall asleep or stay asleep, or you experience excessive daytime sleepiness or fatigue, talk to your primary care physician or seek the advice of a sleep specialist, Dr. Walia says. “Having a good quality and good quantity of sleep is of paramount importance.”
Although individuals may have a natural tendency toward a particular sleeping pattern, you don’t have to be held hostage by your chronotype preference. You can retrain your inner clock by taking control of your bedtime. Here are some suggestions:
• Wake up at the same time every day. Sleeping in on weekends may feel good in the moment, but it perpetuates your evening chronotype and will leave you feeling miserable on Monday morning when you have to get up early again. The best way to reset your circadian clock is with consistency: Establish a regular bedtime, and stick with it. If you absolutely must sleep in, keep it to no more than an extra hour.
• Get a dose of bright light first thing in the morning. When light enters your eye and hits your retina, it sends signals to your brain’s master clock. This cue to your circadian system signals to your body that it is time for wakefulness and activity. Getting a dose of sunlight first thing in the morning can help you reset your internal clock if you do it consistently.
• Minimize exposure to bright light in the evening and at night. Our bodies were designed for natural light in the day, and darkness at night. But with all the artificial light in the modern world —things like television, electronics and even overhead lights — our inner clocks can be thrown off. The more light exposure you have at night, the more your chronotype gets delayed. Do yourself a favor by dimming your screens, wearing blue-light blocking glasses or going screenless after a certain time in the evening.
• Cut out long naps during the day. Taking a nap, especially in the later part of the day, can alter your circadian rhythm and precipitate the evening chronotype. It’s best to avoid naps if you are having trouble falling asleep. If you can’t get through the day without a snooze, keep your nap to less than 20 minutes and take it in the earlier part of the day.
• Avoid regular use of over-the-counter sleep aids. Reliance on medications to help you sleep can have serious side effects for your health. While they may provide temporary relief for occasional sleeplessness, they do not solve long-term problems. Regular use can also mask sleep issues and keep them from being properly diagnosed. Before you resort to taking anything to get more shut-eye, talk to your physicians and get a complete evaluation.