Traditional Chinese medicine is rooted in five thousand years of practice and legitimacy. Naturopathic doctors diagnose imbalances in the body by observing symptoms and examining the tongue and pulses to prescribe a treatment plan addressing individual needs. Chinese herbs, diet therapy and acupuncture (using only sterile, disposable needles) are used to balance the flow of the body's internal energy (described in traditional texts as "qi"), resulting in improved health on physical, mental and emotional planes. Modern medical research has verified the effacy of acupuncture in the treatment of a number of conditions, including osteoarthritis, postoperative dental pain, postoperative and chemoterapy-related nausea and vomiting. Traditionally, the benefits and uses of acupuncture are for more wide ranging.