A calcium deficiency can make it difficult to fall asleep, so eating foods rich in the nutrient, such as broccoli and kale, milk, yogurt and cheese, can help. (Fotolia / September 4, 2013)

Can't get enough sleep? You're not alone. An estimated 50 million to 70 million U.S. adults don't get enough sleep, according to the U.S. Centers for Disease Control and prevention. But hold that yawn! We've got 5 reasons why you need to get enough sleep for your health--and most importantly, 7 sleep remedies to help you get more shut-eye. How much sleep do you need? Aim for 7-9 hours of sleep each night.

Obviously, sleep is important. Being well-rested makes you more alert and keeps your brain sharp (when you're tired, some brain cells actually nod off during the day) and gives you more energy overall. But sleep does so much more.


1. A stronger immune system

Skimping on sleep can compromise your immune system. A 2012 article in the journal Sleep reported that sleep deprivation had the same effect on the immune system as physical stress--such as from an illness or surgery, or grieving for a loved one.

After sleeping eight hours a night for one week, the men in the study were kept awake for 29 hours. This major sleep deprivation caused an increase in certain white bloods cells that are key players in immune activity.

Another recent study published in the same journal found that shorter sleep duration adversely affected study participants' responses to a standard hepatitis B vaccination. Researchers suggest this decreased antibody response may explain why people who don't get enough sleep are more susceptible to infectious diseases.

2. Younger skin

Researchers at Cornell University found that one night of sleep deprivation may cause your skin to lose elasticity, firmness and moisture. It also makes fine lines and wrinkles more noticeable.

3. Healthier heart

When it comes to heart health, research definitely supports the need for a good snooze. Adults who regularly sleep less than six hours a night have an increased risk of heart attacks and developing high blood pressure compared to those who sleep 7 to 8 hours per night. And 7 to 8 hours might be the magic number. Recent studies have also shown an association between excessive sleep (more than 9 hours a night for adults) and cardiovascular disease.

In one study, researchers observed elevated levels of C-reactive protein--an indicator of heart disease--both in women who slept 5 or fewer hours and also (and even more markedly) in those who slept 9 or more hours. And a large Swedish study reported recently in the European Journal of Epidemiology found an association between short sleep duration (5 hours or less per night) and increased cardiovascular events, such as heart attack and stroke.

4. Trimmer waist

If you sleep enough you can lose weight. Plenty of research confirms that adults who sleep less than six hours a night are at higher risk of being overweight. (Among children, sleeping less than 10 hours can cause unhealthy weight gain.)

According to a recent study at the University of Colorado, the effect of sleep may be even more powerful than we realized. The new study indicates that even just a few sleepless nights in a row can cause almost instant weight gain. Participants gained on average two pounds after one week of five-hour nights. Granted, the study was small--16 men and women were tracked for two weeks--but it may have real-world implications.

One reason for this weight gain is because a lack of sleep increases hunger and appetite. Researchers have found a biochemical reason for this: Insufficient sleep can decrease levels of leptin--a hormone that tells us when we've eaten enough and suppresses appetite--and increase ghrelin, a hormone that signals the body to eat by stimulating hunger.

Not only does lack of sleep trigger appetite, it also increases the craving for high-fat, high-carbohydrate foods--aka junk foods. Researchers at Harvard University, for example, found that if you've missed even just an hour or two of sleep, you're more likely to give in to junk food the next day. Other researchers concur, and some brain-imaging studies have even depicted sleep deprivation activating the "junk-food pleasure centers" of the brain.

And there are even more weighty reasons for giving your tired body more sleep. In a small study in the Annals of Internal Medicine, researchers found that when dieters slept 5 hours a night for two weeks, they burned less fat and more muscle than those who slept 8 hours.

A Swedish study published in Sleep Medicine showed that in women under age 50, sleeping less than five hours or more than 10 hours per night was associated with a larger weight size and abdominal fat. Cortisol secretion (the stress hormone linked to belly-fat accumulation) is at its lowest at night, but sleep loss boosts cortisol the day after a night of poor sleep.