Health science

# Overview
Health science is the applied science dealing with health, and it includes many subdisciplines.
There are two approaches to health science: the study and research of the human body and health-related issues to understand how humans (and animals) function,  and the application of that knowledge to improve health and to prevent and cure diseases.
Health research builds upon the basic sciences of biology, chemistry, and physics as well as a variety of multidisciplinary fields (for example medical sociology). Some of the other primarily research-oriented fields that make exceptionally significant contributions to health science are biochemistry, epidemiology, and genetics. See also life sciences and life science academic disciplines.
Applied health sciences also endeavor to better understand health, but in addition they try to directly improve the health of individuals and of people in general.  Some of these are: biomedical engineering, biotechnology, nursing, nutrition, pharmacology, pharmacy, public health, psychology, physical therapy, and medicine.  The provision of services to improve people's health is referred to as health care (see below).  See also branches of medicine.
The health sciences industry, a multi-billion dollar buiness sector, is a cross-section of the life sciences and the health care and medical diagnostics industries.

# Acquisition of health-related knowledge
Medical research is basic and applied research conducted to improve the evaluation of new treatments for both safety and efficacy in what are termed clinical trials, or to develop new treatments (referred to as preclinical research).
The increased longevity of humans over the past century is due in large part to medical research. Among the major advancements in medicine have been vaccines for measles and polio, insulin treatment for diabetes, classes of antibiotics for treating a host of maladies, medication for high blood pressure, improved treaments for AIDS, statins and other treatments for atherosclerosis, new surgical techniques such as microsurgery, and increasingly successful treatments for cancer. New, beneficial tests and treatments are expected as a result of the human genome project. Many challenges remain, however, including the appearance of antibiotic resistance and the obesity epidemic.

# Application of health-related knowledge (health care)
Health care is the prevention, treatment, and management of illness and the preservation of mental and physical well being through the services offered by the medical, nursing, and allied health professions. According to the World Health Organisation, health care embraces all the goods and services designed to promote health, including preventive, curative and palliative interventions, whether directed to individuals or to populations. The organized provision of such services may constitute a health care system. This can include a specific governmental organization such as the National Health Service in the UK,  or a cooperation across the National Health Service and Social Services as in Shared Care.
There are a large number of health professions. The terms medicine or biomedicine, and medical doctor or M.D. refer to the dominant conventional practices in the West. There are a wide range of traditional areas of health care.  The most common areas are: medicine, nursing, midwifery, and various forms of therapy to supplement the healing process and restore proper activity (e.g. Dietetics, recreational, physical, occupational, speech, and  respiratory).
Like health science in general, health care includes both the study and application of preventing and curing human diseases and disorders.  Medical doctors include physicians and surgeons.
There are many different branches of medicine; the other health care professions also have specialties or focus on specific populations or settings of care. Public health studies the effect of environmental factors such as available health care resources on the health of the general population, often focusing on particular populations, such as mothers and children. Dietitians educate people about proper nutrition, particularly specific dietary needs of populations such as people with diabetes, breastfeeding women, and people with celiac disease. Other less common medical areas include first aid and triage.
Dental health has grown in importance in recent decades making dentistry a major field of health sciences. Counselling, hospice care, home care, nutrition, medical social work, alternative medicine, pharmacology, and toxicology are all considered part of health science.
Veterinary medicine is the health science dedicated exclusively to the care of animals. Veterinary medicine is involved in preventing and curing animal diseases and disorders, inspecting animal originated food (like milk and meat)  and animal husbandry.

## Health practices

### Conventional Western practices
- Allopathic medicine
- Athletic training
- Dentistry
- Dietetics
- Epidemiology
- Genetic counseling
- Medical physics
- Medicine
- Medical technology
- Nursing
- Nutrition
- Occupational therapy
- Optometry
- Osteopathic medicine (Note: Osteopathy, as practiced in most countries other than the USA, is listed under complementary and alternative practices below)
- Pharmacology
- Physical therapy (physiotherapy)
- Psychology, including 
- Psychoanalysis
- Psychotherapy, including Cognitive therapy
- Public health
- Physical education
- Speech-Language Pathology
- Surgery, including anaesthesiology
- Veterinary medicine

### Complementary and alternative medicine
- Alexander Technique
- Chiropractic
- Dorn method
- Herbalism
- Holistic health
- Homeopathy
- Hypnosis
- Massage therapy
- Natural medicine
- Naturopathic medicine
- Orthomolecular medicine
- Osteopathy (Note: Osteopathic medicine as practiced in the USA is listed under traditional western practices above)

### Spiritually-based healing
- Christian Science
- Faith healing
- Johrei
- Maharishi Vedic Medicine
- Reiki
- Shamanism

### Traditional medicine and folk medicine
- Ayurveda
- Folk medicine
- Medical herbalism
- Native American traditional healing
- Shamanism
- Traditional Chinese medicine, including acupuncture
- Traditional Korean medicine

### Health practices of historical interest
- Blood letting
- Heroic medicine
- Magnet therapy
- Medieval medicine
- Patent medicine
- Phrenology
- Trepanation

## Contemporary themes
Because health science deals with human life, issues of medical ethics, an important area of ethics, arise frequently.  Medical ethics includes questions on topics such as a patient's right to privacy.  Euthanasia, abortion, human cloning, stem cell research and genetic engineering are especially controversial issues directly related to health science.

# History of health science
The foundations for the Health Sciences fields are as old as the human race.  Humans have always been in need of solutions to address illness, injury, and various health related issues such as childbirth. With modern technology and the backing of the pure sciences, the scientific accuracy of these fields has greatly improved.  Nevertheless, many cultures have used and continue to use various herbs and other culturally specific solutions to help solve health problems that may or may not be backed by any scientific support.