Rationale:

• Genetic and socioeconomic factors influence the prevalence of obesity.

Evidence:

• Obesity runs in families (54; 129).
• Epidemiologic studies show that a number of life events such as smoking cessation (146), pregnancy (310), and other stress factors (311) can enhance the likelihood of obesity.
• Individuals with obese parents are more likely to become obese adults (54).
• Weight gain is common before onset of diabetes (312).
• Children of diabetic mothers are more likely to become obese (23).
• Smoking cessation increases weight gain (146).
• Pregnancy is associated with weight gain (313).
• Weight gain after disability or surgery is common (314).
• Obesity is more prevalent in Latinos, African Americans, and Polynesians (122).
• Obesity is more common in lower socioeconomic groups (122).
• Obesity is more common with less physical activity (141; 315).
• Mutations in the melanocortin 4 receptor gene produce human obesity in up to 5% of very overweight children (316).
• A number of medications produce weight gain (317).

Comments:

• For people taking medications that produce weight gain, alternatives may be available.