Sugar is listed as one of the foods to avoid for fibromyalgia. It plays an impactful role in fibromyalgia pain as it increases pain sensitvity by raising insulin production within the body. However, its drawback does not end just yet. Sugar is also the cause of a common syndrome in fibromyalgia known as Reactive Hypoglycemia. The condition can spark off a series of fibromyalgia symptoms including headaches, fatigue, depression and carbohydrates and sugar cravings etc...