One can compare the concept of yin and yang to the corresponding principle of tridoshas in Ayurveda, the ancient remedy from India. Ayurveda proposes that every person has vata, pitta and kapha. When these are balanced, there is the state of perfect health. When there are imbalances then there is disease. One of the main aims of the acupuncturist is to maintain a balance of yin and yang within the whole person to prevent illness occurring and to restore existing health.
Acupuncture is a yang therapy because it moves from the exterior to the interior.
Herbal and nutritional therapies, on the other hand, are yin therapies, as they move from the interior throughout the body. Many of the major organs of the body are classified as yin-yang pairs that exchange healthy and unhealthy influences. Yin and yang are also part of the eight principles of traditional Chinese medicine. These principles allow the practitioner to use yin and yang more precisely in order to bring more detail into his diagnosis.