Obesity is most commonly caused by overeating and inactivity. If you regularly eat more calories than you burn through activity, you will likely gain weight. Continuing this habit over months or years can lead to obesity.

Diets high in simple carbohydrates, such as sugars, fructose, soft drinks and beer, can increase blood glucose levels, stimulate insulin production and therefore cause weight gain.

A variety of medications can cause weight gain including antidepressants, anticonvulsants and corticosteroids.

Conditions such as hypothyroidism, insulin resistance and Cushing’s syndrome can contribute to obesity.

Genetics — children of two obese parents are more likely to become obese as well.

Inactive lifestyle in combination with poor eating habits — people who lead an inactive lifestyle and regularly eat high calorie meals are more likely to become obese.

Social factors, such as poverty, can put people at higher risk for becoming obese. People who have less income are more likely to eat high-calorie processed foods more often.

If you have recently quit smoking, you are more likely to gain weight. Nicotine increases metabolism to burn more calories.