Millions of people wake up tired every day. They drink liters of coffee, take energy drinks during the day, and at night they can't fall asleep without a sleeping pill. The modern rhythm of life teaches us to attribute chronic fatigue and sleep disorders to stress, overwork, or age. However, evidence-based medicine makes a revolutionary discovery: the real generator of our energy and the "biological clock" are not in the brain, but in the gastrointestinal tract.