Dr. VanWingen: 5 Common Causes of Fatigue

Fatigue is so common in adults that many feel it is just a fact of life. Something they just have to live with.

However, while most of the time fatigue is is simply caused by over-busy days, it's important to know there are many medical conditions which can drain our energy. When I sit with a patient and try to sort out the cause of their fatigue, I ask them to better qualify the nature of the problem “Do you feel like you have just run a marathon or do you feel like you would fall asleep if I left you alone and turned down the lights?”

Fatigue comes in two general categories: physical exhaustion and somnolence (sleepiness).

Causes of "Just Ran a Marathon" Exhaustion Type Fatigue

Anemia - A Shortage of Blood in the Body.

Not making enough blood or loss of blood from the body. This creates a deficiency of oxygen to the tissue of the body and, in turn, fatigue. Sometimes the cause is obvious such as a woman with heavy periods. Most of the time it is not. Doctors can get a better idea as to the cause of the anemia by looking at the size of the red blood cells.

  • When the blood cells are small, loss of blood is a common cause. If the cause of the blood loss is not obvious, the most common place to look is the stool for an ulcer or a polyp.
  • If the cells are normal size, we suspect chronic disease such as diabetes or kidney disease.
  • Finally, if the cells are large, the cause is usually a deficiency of vitamin B 12 or folate.The deficiency of B12 can be due to diet or lack of absorption in the small intestine. Folate deficiency is usually due to severe alcoholism.

Diabetes -  A Glucose Metabolism Disorder.

Six percent of American adults have diabetes and fatigue is a common first sign of this disorder. This is due in part to blood sugar elevation - much like we all feel after we have eaten a big meal or a lot of sugar. The increased blood sugar also causes the kidneys to put out more fluid, leading to a nearly constant state of dehydration.

A simple test of blood sugar can diagnose diabetes.

Hypothyroidism (Low Thyroid) - A Hormone Deficiency.

Low thyroid, or hypothyroidism, is quite common among the general population and even more common in women and in people with a family history of the condition.The thyroid gland which is found in the neck produces thyroid hormone which regulates a number of processes in our metabolism (which provides the body with energy).

Low thyroid slows metabolism and causes fatigue as a result. In addition to fatigue, there a number of telltale signs of hypothyroidism: weight gain, moodiness, bowel irregularities, rash and irregular periods, among them. If this sounds familiar, I urge you to talk to your doctor. A blood test can determine if your thyroid hormone is low. If so, a thyroid supplement can help restore the metabolism and fight fatigue.

Depression - A Mental/Emotional Condition.

Depression can be exhausting on the system. With depression, the neuro hormones that help keep us alert namely norepinephrine (adrenaline) can become deficient. Exercise, therapy or medication can help to boost these hormones back toward normalcy and help correct the problem.

Causes of "About to Fall Asleep" Somnolence Type Fatigue

The most common cause of somnolence is sleep apnea.

This occurs when disordered sleep breathing causes oxygen levels to drop - sometimes  shockingly low. While problematic signals from the brain can cause sleep apnea, nearly all sleep apnea is actually due to “obstructive” redundant tissue in the throat. With this excess tissue, as soon as deep sleep begins, the airway is blocked and causes choking. The person wakes up, only to repeat the process again.

Because deep sleep is most important to feeling rested, these people tend to experience decreased productivity at work, a high rate of depression and can even be a danger behind the wheel. 

Watching these people with sometimes frightening pauses in breathing and displays of the snore-choke-gasp cycles can be like torture. In fact, often times it is the spouse that drags the patient in because they refuse to believe that there is a problem, accepting that this is just how they are - eternally fatigued. Sometimes they even video tape the nightly ritual.

Several fine examples can be found on YouTube:

Risk factors for sleep apnea are obesity and a neck circumference above 19 inches. Diagnosis happens through a study in a sleep lab.

In Conclusion...

Fatigue is common and there are a number of common causes. If a cause is found, it can be dealt with. If no cause is immediately found, the search continues and  it's suspected that the problem may be due to lifestyle issues.If this is the case, an aerobic exercise program and stress management may be the best solution.

Chronic fatigue is not something you "just have to live with."If you suffer from fatigue, see your doctor to begin working toward finding a solution toward a better, not-so fatigued life!

Photo Credit: White Ribbons

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