Risk Factors for Obesity

A risk factor is something that increases your likelihood of getting a disease or condition.

It is possible to develop obesity with or without the risk factors listed below. However, the more risk factors you have, the greater your likelihood of becoming obese. If you have a number of risk factors, ask your doctor what you can do to reduce your risk.

Risk factors for obesity include:

Poor Diet

The following dietary habits can increase your risk of obesity:

  • A diet of high-calorie, low-nutrient foods
  • Consuming more calories than you burn each day
  • Eating quickly, or when you feel full
  • Drinking high-calorie drinks, including sugar-sweetened soda or alcohol
  • High level of fast food intake

Children may also be at risk for becoming obese if they do not eat their regular meals with their family.

Lack of Physical Activity

If you do not get enough physical activity you are likely to burn fewer calories than you eat each day, thus increasing your risk of becoming obese.

For children, too little exercise and spending too much time watching TV or playing on the computer can increase their risk of gaining weight and becoming obese.

Genetic Factors

Obesity may run in families. A combination of genetic and lifestyle factors are likely to a role in the child's excess weight.

In addition, rare hereditary diseases may increase the risk of obesity.

Medical Conditions and Medications

  • History of obesity as a child
  • Some medications, such as steroids and certain antipsychotics, can result in increased appetite and obesity
  • Certain hormonal imbalances, such as hypothyroidism and Cushing’s disease, increase your risk of obesity
  • Polycystic ovary syndrome
  • Larger than normal birth weight
  • Maternal obesity during pregnancy

Psychological factors

  • Harsh physical punishment or abuse during childhood. There is a higher incidence of obesity in adults who were raised in such environments.
  • Post-traumatic stress disorder (PTSD)—Women with PTSD are at increased risk of developing obesity.
  • Family and peer problems.
  • Low self-esteem.
  • Depression and other emotional problems.
  • Stressful life events or changes.

Quitting Smoking

If you are a smoker and want to quit, you may worry that quitting will increase your weight. Keep in mind that you can overcome this weight gain by reducing how many calories you consume and by exercising more. Overall, the health benefits of quitting smoking far exceed the risk of gaining weight.

If you are pregnant, smoking may increase your child's risk of becoming obese.

Other Risk Factors

  • Age:
    • The incidence of obesity increases with age.
    • It more than doubles between the ages of 20 and 55. However, this may be related to a decrease in activity levels.
    • A recent study found that within 30 years, over half of a large group of normal-weight men and women became overweight.
  • Race or ethnicity:
    • There is a higher incidence of obesity among certain races or ethnic groups.
    • In American women—Obesity is more common among African American and Hispanic women.
    • In American men—Obesity is more common in Hispanic men.
    • In American children—Obesity is more common in African American, Hispanic, or Native Americans.
  • Low socioeconomic status.
  • Working shifts at different times of the day and night.
  • Inadequate sleep—general guidelines for children:
    • Aged 5 years or younger—11 hours or more
    • 5-10 years—10 hours or more
    • 10 years or older—9 hours or more


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Last reviewed February 2017 by Michael Woods, MD, FAAP
Last Updated: 2/23/2017

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