What causes this to happen remains unknown, but researchers have identified several triggers for the disease so far.
Sleep deprivation, for example, is a known trigger for symptoms of the disease, like myalgia, tenderness and fatigue.
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Sometimes the condition is brought on by an event that causes physical or psychological stress, like a serious injury or infection.
Between 1.8 and 2.9 millions, people in the UK are thought to have fibromyalgia, with most people between the ages of 25 and 55 being affected.
Source: Daily Express