Acupuncture needles on a stone. Acupuncture is a system of healing that has been practised in Eastern medicine for thousands of years. Chinese philosophy states that our health is dependent on the smooth movement of Qi (energy) through channels under the skin. Illness arises when the components of Qi, Yin and Yang, become unbalanced. Fine needles are inserted into the channels of energy to restore the natural balance of Qi. Acupuncture is now a feature of Western complementary medicine, where it is thought to act as a stimulus for the production of endorphins in the body, which provide an analgesic effect.