Reviewed by Robert Ehrman, MD

You probably know the saying, “Early to bed, early to rise, makes a man [or woman] healthy, wealthy and wise.” It is still good advice. But if you are like many people, you have trouble falling asleep or staying asleep two or more nights a week. At least 40 million Americans suffer from long-term sleep disorders and another 20 million have trouble sleeping at one time or another. Although sleep problems may seem minor when compared with diabetes or other chronic diseases, they cost this country about $16 million every year.

When you do not get enough sleep, it affects your quality of life by keeping you from doing your best work, causing you to feel irritable and withdrawn. It can also affect your health. To learn more, read the answers to the following questions:

Why is sleep so important?

Sleep is just as important for your health as food and water. Although you may not recall your dreams, everyone dreams every night. Even though your body is at rest, your brain is very active. This activity helps prepare you to be alert and at your best the next day.

How much sleep do I need?

Most adults need seven to nine hours of sleep each night to be at their best, but every one of us is a little different. The amount of sleep you need is set by your genes. You can teach your body to get by on less sleep, but your need for a certain amount of sleep will not change. To find out how much sleep you need, go to bed without setting the alarm. The length of time you sleep until you wake up on your own will give you an idea of how much sleep is right for you. When you don’t get enough sleep, you build up a “sleep debt.” The only way to pay back that debt is by getting more sleep.

What does sleep have to do with diabetes?

Studies have shown that not getting enough sleep increases insulin resistance, a major cause of type 2 diabetes. Lack of sleep is also linked to obesity, depression, high blood pressure and heart disease—all common among people with diabetes. In addition, it is hard to care for your diabetes when you are worn out.

What does diabetes have to do with getting enough sleep?

High and low blood glucose levels can interrupt your sleep. When your blood glucose is too high, you may have to get up several times every night to go to the bathroom. When your blood glucose is too low, you may have nightmares or wake up from the symptoms of a low blood glucose level. Pain from neuropathy also can keep you awake at night.

Will I need to sleep less as I get older?

The amount of sleep you need is the same throughout your entire adult life. Older adults often wake up more during the night, so they sleep less, but the need for sleep is the same. As people get older and sleep less at night, they tend to sleep more during the day.

Having trouble sleeping is not a normal part of getting older. If health problems, pain, stress or other issues are keeping you awake, talk with your healthcare provider about treatments that can help.

What is insomnia and what causes it?

Most people think that insomnia is when you have a hard time falling asleep. It is also when you cannot stay asleep, wake up before the alarm, or when you cannot go back to sleep or feel very sleepy during the day.

Stress is the most common cause of insomnia. However, experts have found more than 70 different sleep disorders. Different disorders have different causes. For example, sleep apnea, when breathing stops several times during the night, happens because the airway is blocked during sleep. Narcolepsy, severe daytime sleepiness and sudden sleep attacks, is most likely genetic. No one really knows what causes restless leg syndrome, in which strange feelings in the legs are relieved by moving them. Menopause is another cause of insomnia. Beginning with peri-menopause and moving right through menopause, women make less estrogen and progesterone, a hormone that promotes sleep. Changing hormones and hot flashes also can disrupt your sleep.

What can I do about this?

The first thing to do is keep track of your sleep habits and times you have trouble falling or staying asleep. Write down what you think caused your problem. Then, after one week, look at your diary. Does anything stand out? Be sure to also look at your blood glucose levels during this time. Is there a pattern of blood glucose readings that seem to match your lack of sleep? Keeping your blood glucose level in your target range may help you sleep longer and more soundly. If your sleep problem does not get better, talk with your healthcare provider. There are treatments that can help. So good night, sleep tight, and have pleasant dreams.