Daytime Fatigue and Depression

Sickness behavior is understood as the sum of various symptoms such as discomfort, daytime fatigue, exhaustion, lack of drive, increased feeling of cold, muscle pain, joint pain, loss of appetite, anxiety, depressive feelings, retreat into familiar protected loactions, and “lack of energy.” This program was positively selected for short-term inflammatory situations so that the immune system’s activity is not inhibited. Unfortunately, it is also used long-term in chronic inflammation, and then it is very disruptive. Also, in old age, there is an increase in chronic fatigue due to increasing energy expenditure of various kinds through inflammatory and psychomotor activations. Chronic fatigue can be a precursor to depression.