What is Social Medicine?
Social medicine aims to understand how social and economic conditions impact health, disease and the practice of medicine and then try to work out how we can foster conditions to lead to a healthier society. Social Medicine focuses on the wider determinants of health or 'upstream' factors and include housing, education, income, poverty, transport, health care organization and environmental and genetic influences. By targeting these factors we can prevent illness from happening and so save costs and lives.
A good way of illustrating 'upstream' factors is if you picture a health professional as a lifeguard on the bank of a river. Every now and then someone floats by and the health professional has to jump in and rescue them. Sometimes it's a body and other times there may be rapids or lots of people drowning. The health professional can only help one person at a time. It is tiring and costly. One day s/he may have a few moments to think about why so many people are falling into the river. What is happening upstream? If you can prevent people from falling into the river in the first place, fewer people will be at risk and the health professional's work would be easier.
So how does it differ from public health?
Social medicine uses social science and humantities research to improve the practice of medicine, the delivery of treatment and development of healthcare policies. Public health work applies the findings of social medicine to improving services and the health of populations. Social medicine is often said to be made up of social epidemiology, social psychology, medical geography, medical sociology and health economics. In some places, it is considered the academic arm of public health whilst others have called it the bridge between medicine and public health.
If you wish to find out more about social medicine, see The Society for Social Medicine.
There is also a journal Social Medicine which is full of interesting articles on the latest research in the field. Linked to this is the Social Medicine Portal which can tell you more about the field, especially the work being done in the United States.
An interesting introductory read is http://www.med.unc.edu/socialmed/about/madison-1993 which explains how social medicine evolved from being an application of medical insights to social problems in 19th century to the multi-disciplinary field today.