Why So Tired?

You could be suffering from fatigue if you're getting enough shut-eye, but still find yourself falling asleep during the day.

Early Show Medical Correspondent Dr. Emily Senay provides some clues that may reveal the roots of your grogginess.

Dr. Senay says there is nothing wrong with occasionally feeling fatigued. She says we all have days where we aren't running at full speed because we didn't get a good sleep the night before. There are a number of reasons for the occasional sleeplessness.

Maybe you had a stressful day at work and can't sleep because you are worried. Maybe you ate something that didn't agree with you and it's causing you to stay awake. But if you find yourself constantly fatigued and it's not for a lack of sleep, you need to see if something more serious is causing you to be groggy.

Sleep Apnea

There are several hidden causes of fatigue. One cause, according to Dr. Senay, is apnea. Sleep apnea affects an estimated 12 million Americans. A person with it will stop breathing many times during each night's sleep. In severe cases, the number of times a person stops breathing can be over 100 times in an hour. Loud snoring is a common symptom of sleep apnea. It primarily affects men. Sleep apnea is more common in overweight people, so you may want to consider dropping a few pounds. You'll also want to avoid alcohol before bed, which can exacerbate the problem.

Allergies

A common symptom of allergies is a heavy feeling in your eyes and a foggy feeling in your head. This can lead to someone being tired. Many allergy sufferers turn to over-the-counter medications to ease the symptoms. In some cases, these medications can make the problem worse. Look for one of the newer antihistamines such as Allegra or Clarinex, which relieve symptoms but don't cause drowsiness. If your allergies are serious, you may want to consider getting allergy shots.

Anemia

According to the Centers for Disease control, about 3.5 million Americans have anemia. Dr. Senay says anemia occurs when the body produces too few red blood cells, loses too many of them or if red blood cells are destroyed faster than they can be replaced. People with the condition often lack energy. The good news is that a simple blood test can detect some types of anemia. If your doctor does conclude you have anemia, she can prescribe medications or a change in diet.

Underactive Thyroid

Dr. Senay explains that the thyroid may also affect your sleep. The thyroid is a small gland in the neck which secretes hormones that control your metabolism. In a person with an underactive thyroid, not enough of the hormone is being secreted, which can lead to insomnia and/or fatigue. An underactive thyroid typically affects women around 50 years old. A doctor can prescribe hormone replacement to alleviate the problem.

Depression

For some, depression could be the cost of bad sleeping behavior. Dr. Senay believes depression can wear down the body. A depressed person is typically thinking negative thoughts all the time, which, after a while, can be physically exhausting. She says if you find yourself in this situation, get in touch with your doctor who can prescribe medication or psycho-therapy. There are many newer antidepressants out there that can relieve your symptoms without causing many side effects.

Mitral Valve Prolapse Syndrome

Dr. Senay says a heart mumur may make one tired, too. Mitral valve prolapse syndrome is a problem with the nervous system that is associated with a heart murmur. In some people with the condition, blood volume drops below normal levels. To make up for this deficiency, the body releases extra adrenaline to speed the heart up, which can lead to problems such as a racing heart and fatigue. The good thing about this condition is that it is typically treated with modest lifestyle changes.

Chronic Fatigue Syndrome

The last cause that may cause tiredness is chronic fatigue syndrome. Dr. Senay says it is a condition of prolonged and severe tiredness or weariness that is not relieved by rest and is not directly caused by other conditions. The exact cause of chronic fatigue syndrome is unknown. Some researchers suspect it may be caused by a virus — such as human herpes virus-6. However, no distinct viral cause has been identified. Recent studies have shown that chronic fatigue syndrome may be caused by inflammation of pathways in the nervous system; and that this inflammation may be some sort of immune response or autoimmune process.

Dr. Senay says there is currently no treatment that has been proven to be effective in curing CFS. Instead, the symptoms are treated. Many people with CFS experience depression and other psychological problems that may improve with treatment.