The risks you face when you don't get enough sleep

Getting a good night's sleep is often more easily said than done. The realities of modern life mean that we have far more distractions and sleep stealers than ever before. We can work, shop and bank 24 hours a day right from our living rooms.

It doesn't get easier as we get older. With age, we tend to sleep more lightly and for fewer hours, although our sleep needs don't change. Contrary to what some sleep-deprived folks may claim, you cannot "train" your body to require less sleep.

You become sleep deprived when you don't get sufficient sleep to stay alert and function well throughout the day. The effects of sleep deficiency are cumulative.

As a result, you can build up a sleep deficit that grows each night you lose sleep and must be paid back. After several nights of sleep loss—even an hour or two each night—you'll begin to function in the same way as if you haven't slept at all for one or two days.

If you miss out on two hours of sleep each night, after one week you'll have accumulated a 14-hour sleep debt. If you routinely don’t get proper sleep, your sleep debt can't be remedied by sleeping in on weekends.

About half of all people over age 65 have frequent trouble sleeping. Not getting adequate sleep can have serious consequences. Sleep deficiency has played a role in several high-profile tragic accidents such as nuclear meltdowns and the grounding of an oil tanker. On our roads, drowsy drivers are responsible for an estimated 100,000 motor vehicle accidents and 1,500 deaths each year, according to the National Highway Traffic Safety Administration.

Even more common are the potential day-to-day health consequences from lack of shut-eye. Sleep deficiency is linked with significant physical and mental health effects, including

  • cognitive deficits,
  • cardiac issues,
  • obesity,
  • impairment of memory,
  • and
  • impaired immune function.

Among the most recent research, published online in March 2013 by the European Heart Journal, were findings from an 11-year Norwegian study of more than 54,000 people, ages 20–89, that concluded participants with multiple insomnia symptoms had a fourfold increased risk of heart failure compared with those who had no insomnia symptoms.

Researchers found insomnia symptoms were more prevalent among older adults and women. Since this was an observational study, scientists can't say that insomnia actually causes heart failure, just that there's an association. More research is needed to learn what the connection is between the two.

Source: Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50

Publication Review By: the Editorial Staff at

Published: 10 Jul 2013

Last Modified: 08 Sep 2015