Although people who smoke cigarettes tend to weigh less than people who do not smoke, the risks from smoking are greater than those of being obese. Lack of activity is an important factor in the increasing incidence of obesity. Walking or cycling instead of using a car, going to exercise classes and taking part in team sports such as football or basketball can all help a person maintain a healthy body weight by increasing energy output. Any form of activity or exercise that people enjoy should be encouraged. People who are already overweight are usually encouraged to become more active as well as reducing the amount of energy provided by their diet.
All diets containing more energy than a person needs can cause weight gain.
It may also be that excess dietary fat is more easily converted to body fat than excess carbohydrate or protein . If someone is obese, they will usually need advice from their doctor or dietitian about a suitable weight-reducing diet. This can be a good opportunity for someone to make general improvements to their diet. Special slimming products are not necessary. Preventing obesity is important, as dieting is difficult and often fails.