Life style medicine is a clinical discipline based on facts (“evidence”) that deals with lifestyle interventions that affect health and quality of life. It could also be defined as the “application of medical, environmental, motivational and behavioural principles to clinical and therapeutic management of health problems related to lifestyle”.In addition to prevention of illness (risk reduction), lifestyle medicine also focuses on its therapeutic management (if such a condition is already present), often in a more cost-effective way than conventional treatments based on drugs and surgery. The enormous potential effects of such lifestyle interventions on mortality, morbidity and healthcare costs are more than sufficient incentives for interest in lifestyle medicine.Examples of such interventions include, but are not limited to, all of the following: cessation of tobacco use, balanced diet, weight control, increased physical activity, moderate alcohol consumption; adequate sleep and rest, and increased mental and emotional well-being. Lifestyle medicine was originally developed in the United States. There, as well as in Spain,various medical associations and ongoing projects exist related to lifestyle medicine. While it is a new discipline, lifestyle medicine does not purport to be an alternative to conventional medicine, but rather a complementary strategy to deal with the clinical challenges that modern lifestyle changes represent.