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Obesity is a medical condition in which the sufferer has so much body fat that it has an adverse effect on their health, leading to reduced life expectancy.
Obsessive-compulsive disorder (OCD) is an anxiety disorder
that causes people to have unwanted thoughts (obsessions) and to repeat certain
behaviours (compulsions) over and over again. However, these patterns of
behaviour get in the way of their daily lives. Most know that their obsessions
and compulsions make no sense, but they can't ignore or stop them.
Osteoarthritis is an umbrella term for a group of diseases which entail degradation of the joints by arthritis.
Osteomyelitis is an inflammation of the bone or bone marrow which is caused by a bacterial infection, usually from Staphylococcus aureus or a species of Salmonella.
Osteoporosis is the term used to describe the condition where the bones — particularly those of the spine, wrist, ankle and hips — become thin and weak through the progressive loss of minerals, mass and density, and are prone to break easily.