Health and medicine

How the body works, what illness is, and what the evidence says.

Medical knowledge changes as evidence accumulates. These pages describe conditions and treatments as the sources do — they are not medical advice.

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• Immune system Biological system protecting an organism against disease

  The immune system is a network of biological systems that protects an organism from diseases. It detects and responds to a wide variety of pathogens, such as viruses, bacteria, and parasites, as well as cancer cells and foreign objects, such as wood splinters—…

• Vaccine Preparation for acquired immunity to disease

  A vaccine is a biological preparation that provides active acquired immunity to a particular infectious or malignant disease. The safety and effectiveness of vaccines has been widely studied and verified. A vaccine typically contains an agent that resembles a …

• Diabetes Group of endocrine diseases characterized by high blood sugar levels

  Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes tends to progress in severity, and is due to either a reduced production of the hormone insulin by the pancreas …

• Human brain Central organ of the human nervous system

  The human brain is the central organ of the nervous system, and with the spinal cord, comprises the central nervous system. It consists of the cerebrum, the brainstem and the cerebellum. The brain controls most of the activities of the body, processing, integr…

Questions in this topic

• What is the immune system?
• How do vaccines work?

Related topics

• Science — Biology, chemistry and physics — how the natural world actually works.

Where this comes from

Every page here is built from published text on en.wikipedia.org and from the open research services listed on the sources page. Nothing is written by a model, and every claim links to the page it came from.