Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have a negative effect on health, leading to reduced life expectancy and/or increased health problems.
It increases your risk of diseases and health problems such as heart disease, diabetes and high blood pressure. Being extremely obese means you are especially likely to have health problems related to your weight.
Fat is deposited on our bodies when the energy (kilojoules) we consume from food and drink is greater than the energy used in activities and at rest.
Small imbalances over long periods of time can cause you to become overweight or obese.