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If you have a hectic family life, a busy career, or both, it’s easy to push sleep to the back burner, telling yourself you’ll catch up “later.”

But that hour of sleep you gained last weekend as we switched from daylight saving time to standard time doesn’t begin to make up for the shortfall. For optimal health, you need a good night’s sleep every night.

If you sleep fewer than the recommended seven to eight hours every night, should you lie awake worrying about it? Our primary care concierge doctors in Jupiter certainly hope not.

But we think it’s important to remind our patients that adequate sleep on a regular basis is essential to good health, and now a new study seems to show why.

Consequences to Health

The health issues associated with lack of sufficient sleep affect every part of the body and can trigger numerous diseases: obesity, type 2 diabetes, cancer, cardiovascular disease, dementia, depression . . . even a shorter lifespan overall.

For years, science has known that insufficient sleep leads to these and other diseases, but no one was sure why.

Now a study published in September in the Journal of Experimental Medicine has linked lack of sleep to inflammation, a condition that can result in long-term damage throughout the body.

The study by researchers at the Icahn School of Medicine at Mount Sinai in New York City showed that chronic sleep deprivation in healthy adults increased the production of immune cells linked to inflammation, while at the same time changing the immune cells’ DNA to impair their protective abilities.

“Not only were the number of immune cells elevated but they may be wired and programmed in a different way at the end of the six weeks of sleep deprivation,” said study co-author Cameron McAlpine, an assistant professor of cardiology and neuroscience at Mount Sinai.

“Together, these two factors could potentially predispose someone for diseases like cardiovascular disease,” he said.

The Study

Although small, the study was carefully crafted to measure the effects of restricted sleep on a group of 14 healthy men and women, of average age 35, who normally sleep eight hours a night. The researchers checked the immune cell content of the volunteers’ blood over the course of six weeks, as their sleep time was reduced from their normal eight hours to 90 minutes less during the study.

They found that during the period of sleep restriction, the volunteers’ immune cells increased, suggesting an increase in inflammation as a result. Furthermore, the stem cells which create new immune cells appeared to be permanently damaged over the study period.

“The key message from this study is that sleep lessens inflammation and loss of sleep increases inflammation,” said study co-author Filip Swirski, director of the Cardiovascular Research Institute at Icahn Mount Sinai.

“In subjects who had undergone sleep restriction, the number of immune cells circulating in the blood was higher. These cells are key players in inflammation,” he added.

Long-term Damage

One researcher who was not involved in the study, Kristen Knutson, an associate professor at the Center for Circadian and Sleep Medicine at the Northwestern Feinberg School of Medicine, called this new study’s design “elegant.” 

While many studies of this type are restricted to one or two nights of sleep deprivation, this one lasted much longer. Moreover, it was conducted on healthy adults, who were monitored in a clinical setting, rather than relying on self-reporting of sleep duration.

“They emphasized the long-term effects of sleep impairment that we don’t quickly recover from and they showed this in both animal and human studies,” Knutson told NBC News.

Another doctor who also was not involved in the study agreed. Stephen Chan, director of the Vascular Medicine Institute at the University of Pittsburgh School of Medicine, told NBC News that this new study explains how chronic lack of sleep could weaken the immune system.

“We fundamentally did not understand why at the cellular level, sleep was so important in the control of the immune system [prior to this study],” he said.

“It’s really important to understand how sleep might impact inflammatory diseases like sepsis, cardiovascular disease, Alzheimer’s, and dementia,” he explained.

Prioritizing Sleep

Although we need a certain amount of inflammation in the body to recover from injuries or illness, too much over a long period of time causes damage throughout the body and can lead to chronic disease.

And Swirski explained that, although the increase in immune cells may return to normal after a few weeks of adequate sleep, their study showed that the damage to the stem cells may be more permanent, impairing their ability over time to perform well.

As we said earlier, we don’t want to make you so nervous about missing a bit of sleep that you lie there staring at the clock every night and worrying.

But we do want to emphasize the importance of making sleep a priority in your schedule.

And to help you sleep better, you should:

• Go to bed at the same time every night.
• Don’t try to sleep on a full stomach.
• Refrain from using caffeine or alcohol after dinner.
• Turn off “blue-light” devices (TVs, computers, smartphones) at least an hour before bedtime.
• Restrict activity in the bed to sex and sleep (i.e., no working, reading, TV, etc.).

Let us know if you have any difficulty falling asleep or staying asleep. We can help uncover the causes and provide solutions.