Doctors of Chiropractic study the anatomy and physiology of all human body systems, such as organs and immune system, cardiovascular system. More advanced study is dedicated on how muscles, tendons, ligaments, joints and bones of the spine and extremities affect the nervous system to produce symptoms and decrease human function. Chiropractic is a holistic profession which utilizes many different non drug therapies and treatments. Chiropractors are the experts in a type of treatment the profession calls an adjustment. This treatment has been shown in numerous scientific studies to be the one of the safest, painless and most effective treatment for relief of spinal pain. But this therapy can be used to for relief of many other symptoms. And should be used by all human beings for wellness purposes because of how it improves and maintains better nervous system function.