Endorphin is a chemical substance made of proteins and produced in the pituitary gland of the brain. It acts on the central and the peripheral nervous systems in suppressing pain.
Enkephalin is a type of endorphin and also a natural pain killer, working to inhibit the transmission of pain in the pathway for pain perception. This lessens the emotional and the physical impact of pain.
Research is revealing how these two natural opiates might also serve other roles.
Enkephalin might be involved in the development of psycho-pathological behavior in some people. Endorphin might also exert profound effects on moods, higher production being associated with a person's sense of well-being.
Increased levels of these chemical substances might also prevent an immune system from being weakened by such psychological states as depression or bereavement.
People prone to depression, alcoholism, or drug addiction are often deficient in endorphin levels.

How to increase endorphin levels?

Regular aerobic exercise is believed to elevate endorphin levels.This is the so-called “runner’s high”.
Meditation, prayer and relaxation response training also elevate endorphin levels.