Several factors can trigger high blood sugar levels. These include:

• Excessive sugar intake. Chronic fatigue syndrome (CFS) can drive sugar cravings, and excess sugar can aggravate CFS — leading to even more sugar cravings.

• Low testosterone in men. Seventy percent of men with CFS are in the lower third of the normal range for testosterone levels, and low testosterone in men increases the risk of insulin resistance and diabetes.

• Elevated testosterone in women. Paradoxically, elevated testosterone in women can cause the high blood sugar levels characteristic of insulin resistance and type 2 diabetes. A common cause for these high levels is polycystic ovarian syndrome (PCOS), which is a syndrome that can cause CFS/fibromyalgia. You should consider this possibility if you're a woman with elevated levels of testosterone and/or DHEA, facial hair growth, acne, and/or unexplained infertility. Treat PCOS with the safe, cheap and healthy anti-diabetes medication metformin and by avoiding excess sugar. Other treatments can also help, such as making sure your body is getting adequate levels of the glucose-regulating mineral chromium. Treating PCOS is not only effective for decreasing CFS/FMS symptoms, it can also resolve some cases of infertility.

In any of these three conditions optimizing blood sugar levels and insulin sensitivity can improve CFS symptoms.