Symptom

Change in weight

An unexplained change in weight – either gain or loss without an intentional change in diet or exercise – may be a sign of a treatable condition.

Weight loss may be associated with overactive thyroid, diabetes, cancer, inflammatory bowel disease or depression. Weight gain may be influenced by hypothyroidism, hormonal changes, medication or Cushing’s syndrome.

A doctor investigates the cause with blood tests, hormone measurements and, if needed, imaging studies. Early diagnosis makes treatment easier.

Frequently asked questions

How much weight change is a reason to see a doctor?

Seek medical assessment if your weight has changed by more than 5% of your body weight within 6–12 months without a deliberate change in lifestyle. Rapid unintentional weight loss is especially a reason for urgent evaluation.

Can hypothyroidism cause weight gain?

Yes. In hypothyroidism, metabolism slows down, which can cause weight gain, fatigue, feeling cold a lot, and dry skin. The diagnosis is made with a blood test (TSH, T4), and the treatment is thyroid hormone replacement therapy.

Can depression cause weight change?

Yes. Depression can cause both weight loss (loss of appetite) and weight gain (emotional eating, reduced exercise). Antidepressants may also affect weight. Untreated depression is often the most significant factor in weight change.