Our body is kept in balance by our sympathetic nervous system, which facilitates action, and our parasympathetic nervous system, which facilitates rest and recovery. During stress, we experience pressures that outweigh our coping abilities. As a result, our body senses danger and activates our sympathetic nervous system. This can occur even without our awareness of the stressors.
Chronic fatigue syndrome, known technically as myalgic encephalomyelitis, appears to be caused by any of several factors: infection, hormonal changes, issues with the immune system, or a combination of these. Intriguing new research points to an additional possibility: damage to mitochondria in living cells.