It's hard to be your best, professionally and personally, if you don't get enough sleep. In fact, a lack of sleep isn't just something that can make you feel and look tired. It can have serious consequences for your quality of life and your health.

According to the Centers for Disease Control and Prevention (CDC), 50 to 70 million U.S. adults have a sleep disorder -- and sleep insufficiency is now recognized as a public health problem linked to car crashes and occupational errors. What's more, CDC statistics show that not getting enough sleep regularly raises your risk for chronic diseases such as hypertension, diabetes, depression and even obesity. Researchers have noted changes in body metabolism and an increase in carbohydrate cravings are closely linked to poor sleep patterns.

Lack of sleep may even play a role in the development of some cancers. For example, a study published in the journal Cancer by researchers from University Hospitals Case Medical Center and Case Western Reserve University School of Medicine found people who got less than six hours of sleep at night had an almost 50% increase in the risk of precancerous polyps which, if left untreated, can develop into colon cancer.

But there's good news. Even if getting enough restful snooze-time seems like an elusive dream, there are strategies to find out what's keeping you awake -- and ways to help you get the restful sleep you need.

Why you can't sleep

If you frequently have difficulty falling asleep at bedtime, awaken many times during the night or wake early in the morning and have trouble falling back to sleep, you probably have insomnia. One type, known as secondary insomnia, results in difficulty sleeping because of a health condition such as heartburn, painful arthritis or depression. However, the most common type, primary insomnia, isn't directly associated with other health problems -- but it can still make you feel grumpy and downright miserable from fatigue.

David Schulman, MD, MPH, medical director of Emory's Sleep Laboratory in Atlanta, Georgia, tells us that most people who wake up feeling unrested fit into one of three groups of people who don't get enough sleep.

"One possibility is that you lack quantity of sleep. People usually recognize they are fatigued because they are trying to get by on five hours of sleep and it's not enough," he explains. How do you know how much sleep you need? Although most people require seven or eight hours of sleep a night, the need varies between individuals. However, Dr. Schulman says that if you have to rely on an alarm clock to wake up, you are probably not getting enough sleep.

If you seem to be getting enough hours of sleep but still wake up tired, the quality of your sleep is likely poor because of disruptions -- ranging from a host of things such as a dog barking to a partner who tosses and turns or snores.

"A third group of people who simply never seem to awake refreshed have a greater drive to sleep because they have the condition known as narcolepsy," Dr. Schulman explains.

Tips for improving your sleep

• Don't fall asleep with TV or any lights on. "Slight changes in noise from the television and from lights can make a significant impact on sleep by causing arousal," Dr. Schulman says.
• Avoid caffeine within 10 to 12 hours of bedtime.
• While regular exercise is great for health and a stress buster, don't workout after 4 or 5 o'clock in the afternoon. "Those fight or flight hormones stick around in the bloodstream and make it a harder to fall asleep," Dr. Schulman explains.
• Taking a warm bath or shower can help you cruise into snooze land.
• If you need a night time snack, Dr. Schulman advises sticking to an ounce of protein such as meat, cheese or milk -- but skip the left over pizza or cupcakes. "Don't eat a big meal within a few hours of going to bed and especially avoid eating carbohydrates before sleep," he adds. "We think carbs affect blood sugar levels and can cause significant sleep disruption."
• Don't drink alcohol within two or three hours of bedtime. Dr. Schulman points out that a drink may help you go to sleep at bedtime, but it won't help you stay asleep. After your body has metabolized the alcohol in an hour or two, it can cause you to wake up.
• If you cannot sleep peacefully due to a bed partner who tosses and turns or snores, you need to address the problem. Sleeping in separate bedrooms may not sound romantic, but they could help your relationship by allowing you to get adequate rest.
• Make your bedroom a peaceful haven for sleeping. "Especially if you have insomnia, your bedroom and especially your bed should not be used for watching movies or as a place where you do work," Dr. Schulman advises.

When to talk to your doctor

Lack of adequate and restful sleep has too many potentially serious consequences to ignore. So don't hesitate to contact your physician or a sleep specialist if self-help measures don't work. It's especially important if you or your partner snore loudly with witnessed breathing pauses during sleep -- these are signs of sleep apnea, a potentially serious but treatable disorder in which breathing repeatedly stops and starts, disrupting sleep.

Relying on over-the-counter sleeping aids or prescription medication more than once a week routinely to sleep should be a wake-up call to call your doctor, too. "Taking sleeping pills may be masking a disorder that needs treatment," Dr. Schulman explains. "Even if you have primary insomnia, not an illness, there are a lot better things than medication to help you sleep."

For example, he recommends relaxation techniques such as meditation, yoga and cognitive behavior therapy (CBT). "Overseen by a psychologist, CBT helps you get control of thoughts and emotions that can keep you from getting adequate sleep. It's not a quick fix and can take a few weeks or months, but it works."