We consider obesity to be a disease that can have genetic, medical, lifestyle, and environmental causes, including:
Eating more food than the body burns in activity such as, eating large portions or filling up on high-calorie junk food.
Not getting enough physical activity (for example, spending too much time watching TV or playing video games).
Environmental factors that make it difficult to eat healthy or get enough exercise, such as living in an area with few playgrounds or grocery stores that carry healthy affordable food
Some diseases and conditions, such as hypothyroidism, can cause weight problems. In addition, some medications, such as steroids, can cause children to gain weight.
A family history of obesity can make it more likely that children have weight problems.