If you have chronic fatigue syndrome (CFS) and you're female, you probably woke up this morning with a really low cortisol level. A study accepted for publication in the Journal of Clinical Endocrinology & Metabolism (JCEM) links low levels of the hormone to severe fatigue in female CFS patients - but not in male patients.
Cortisol is one of the weapons your body uses to fight stress, and in CFS, low levels may be what makes it hard to deal with not only psychological stress, but also physical stresses such as infection and exertion. Other research has shown differences in cortisol levels between men and women, including a recent study that found an unhappy marriage led to lower levels in women, but not in men. These differences could help explain why women are so much more susceptible to CFS.
What I find most exciting about this study isn't that it confirms differences in cortisol levels between those with and without CFS or between men and women. What really caught my attention was that most of the researchers are with the CDC. That's right, doctors with the Centers for Disease Control and Prevention are actively looking into biological indicators of CFS.
It was only in 2006 that the CDC acknowledged studies had provided credible evidence that CFS might have a biological basis, so to have these guys now working to find even more evidence seems to be a sign that the tides have turned. If the CDC is taking chronic fatigue syndrome more seriously, it could help convince more members of the medical community that it's a real medical condition and not an issue of psychology or whining. If you have any chronic doubters in your life, maybe they need to take a close look at this study and who's involved in it.