Stress is the reaction a person has to a threat of danger, whether real or imaginary. Stress causes a great amount of energy and hormones (the so-called stress hormones) to be used up. Therefore, adequate nutrition is required with a large quantity of vitamins and minerals, as well as food, which increases energy, calms nerves, lowers blood pressure and enables the body to withstand any threat of danger. Excessive stress weakens the immune system.