What Makes Chronic Fatigue Syndrome More Likely?

Medically Reviewed by Arefa Cassoobhoy, MD, MPH on November 20, 2020

Anyone can get myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Experts aren’t exactly sure what causes it, but they believe certain people might be at greater risk.

If you think you may have it, or are concerned that you could be at risk, check with your doctor.

Age and Gender

If you’re a woman, you’re four times more likely to get ME/CFS than men. The condition is rare in children, but girls are more likely to develop it than boys.

The illness most often begins in adults aged 30-50. With teenagers, those between 13 and 15 seem to have it most often.


Chronic fatigue syndrome ME/CFS can run in families. It’s possible that some people inherit a risk for it from one of their parents, such as inheriting a defect in how a particular gene is built.

Probably more important than how genes are built is whether genes are turned on or off properly—differences in gene activity. In people with ME/CFS, within white blood cells and other parts of the body, there are differences in gene activity. For example, several studies have found that genes important in activating the immune system are more likely to be turned on in people with ME/CFS.

Most diseases are determined both by how genes are built and by things in the environment—infectious organisms, toxins, diet, stress, exercise patterns, etc.  This may well be true in ME/CFS, as well.

Other Conditions

People with chronic fatigue syndrome might be more likely to also have some of the following conditions:

It’s possible that having one of these conditions could raise your risk for ME/CFS. Or it could be the other way around. So far, researchers don’t completely understand the relationship between chronic fatigue and these other health problems.


Show Sources


Centers for Disease Control and Prevention: “Chronic Fatigue Syndrome.”

Kids Health: “Chronic fatigue syndrome.”

National Health Service (U.K.): “Chronic fatigue syndrome.”

Rimes, K. Pediatrics, March 2007.

Heim, C. JAMA Psychiatry, November 2006.

Genetics Home Reference: “Corticosteroid-binding globulin deficiency.”

Schlauch, K. Translational Psychiatry, published online February 9, 2016.

Kerr, J. Current Rheumatology Reports, December 2008.

Aaron, L. Journal of General Internal Medicine, January 2001.

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