Pop a pill to boost your brainpower — it’s been a theory for a while but may now be closer to reality.

For many older people, joints can get stiff and painful from osteoarthritis. This disease often settles in the knee. While it can be hard to sleep with an aching knee, poor sleep may be contributing to the pain.

One of the most common symptoms of multiple sclerosis (MS) is fatigue. And new research suggests fatigue may be common among MS patients because they have undiagnosed sleep disorders.

People with multiple sclerosis already may feel tired during the day or have difficulty sleeping. But an undiagnosed sleep problem could make matters worse.

More than 18 million American adults have sleep apnea. The condition is more common in the elderly, especially those with Alzheimer’s disease. 

Poor sleep is linked to a wide range of possible ailments. However, it also works the other way around. Poor sleep can also be a sign that illness is contributing to the bad sleep.

Military service can be brutal on a person's body. But it may be even more brutal on a person's sleep. Insomnia, sleep apnea and too little sleep appear common among military personnel.

Wouldn't it be nice to spend an extra few hours in bed each morning? Chances are, you would get all the sleep you need - and you may feel less pain during the day.

When it comes to chronic pain, a positive attitude may be just as effective as a painkiller if a person can successfully put the pain out of their mind. And they’ll sleep better too.

Chronic fatigue syndrome ( CFS ) is a complex disorder that affects more than one million Americans. A couple of years ago, a study was released that claimed that XMRV (a gammaretrovirus ) was a contributing factor in developing CFS . But now, scientists say that is not the case.