What are some medical reasons for weight gain?

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Some illnesses and medical conditions can make you gain weight, which increases your risk for becoming obese. For example, an underactive thyroid gland can promote weight gain. This butterfly-shaped gland in your neck produces hormones, or chemical messengers, that help determine how much energy your body uses. If your thyroid is underactive (a condition called hypothyroidism), your body may burn fewer calories, which could make you gain weight.

Medications prescribed to treat certain medical conditions may promote weight gain. These medications include antidepressants, anti-psychotics, birth control pills and certain diabetes drugs.

There are some medical conditions that can cause you to gain weight or make weight loss harder than it normally would be. If you are trying to lose weight and failing, or if you are gaining weight for no apparent reason, check with your physician to rule out medical causes such as hypothyroidism, food sensitivities, blood sugar imbalance or Cushing's syndrome. In addition, ask whether it may be a side effect of a prescription medication such as steroids, nonsteroidal anti-inflammatory drugs (NSAIDs), diabetic medications or antidepressants.

Also, if you are restricting calories too much or exercising excessively, your body will hoard calories and fat to prevent starvation. A good moderate plan should include no fewer than 1,200 calories per day for women and 1,500 calories per day for men.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.