Unintentional weight gain is an increase in body weight that occurs when a person takes in more calories than the body needs or uses.

Almost 40% of all Americans are overweight. As we age, our metabolism slows, which can cause weight gain unless we also reduce the amount of food we eat and get adequate exercise.

Weight gain can also be a significant symptom of several endocrine diseases such as Cushing syndrome or hypothyroidism. It may also indicate a heart or lung disorder.

A continued weight gain occurs with pregnancy, whereas a periodic weight gain may occur with menstruation. A rapid weight gain may be a sign of dangerous fluid retention.

• Alcohol use
• Certain drugs such as corticosteroids, cyproheptadine, lithium, tranquilizers, phenothiazines, some antidepressants, and medicines that increase fluid retention and cause edema
• Cushing syndrome
• Eating too much and exercising too little
• Emotional factors such as guilt, depression, and anxiety
• High-carbohydrate, high-calorie diet
• Hypothyroidism
• Polycystic ovary syndrome
• Slower metabolism, which is normal with aging
• Quitting smoking

Take action by starting a proper diet and exercise program. Counseling may be helpful.

Set realistic weight goals to maintain a healthy weight. Consult with a health care provider about specific measures.

Contact your health care provider if the following symptoms occur along with the weight gain:

• Constipation
• Excessive weight gain without a known cause
• Hair loss
• Sensitivity to cold
• Swollen feet and shortness of breath
• Uncontrollable hunger accompanied by palpitations, tremor, and sweating
• Vision changes

Your health care provider will perform a physical examination; measure your height and weight to calculate your body mass index (BMI); and ask questions about your weight gain, such as:

• Are you anxious, depressed, or under stress?
• Did you gain the weight quickly or slowly?
• Do you have a history of depression?
• Do you use alcohol or street drugs?
  • Does the weight gain cause you much concern?
  • Has your participation in social activities decreased?
  • Has your physical activity been restricted due to illness or injury?
  • Have there been changes in your diet or appetite?
    • How much weight have you gained?
• What medications do you take?
• What other symptoms do you have?
• When did the weight gain begin?

Tests that may be done include:

• Blood tests including chemistry profile
• Measurement of hormone levels
• Nutritional assessment

Weight gain caused by emotional problems may require psychological counseling. Talk to your health care provider about an appropriate diet and exercise program and realistic weight loss goals. If weight gain is caused by a physical illness, treatment (if there is any) for the underlying cause will be prescribed.

If weight continues to be a problem despite diet and exercise, talk with your health care provider about other treatment options, including medications and surgery.

Position of the American Dietetic Association: Weight Management. Journal of the American Dietetic Association. Feb 2009;109(2): 330-346.