Losing 5%+ of body weight over 6-12 months without trying deserves a workup - thyroid, diabetes, depression, gut absorption problems, and cancer are the cause families doctors check.
What to do
Common questions
Why am I losing weight without trying?
Losing weight without changing anything is your body volunteering information, and doctors have a firm rule about it: losing 5 percent or more of your body weight over 6 to 12 months without trying deserves a workup. MedlinePlus lists the cause families, and they split into a few buckets. The common, fixable ones: an overactive thyroid, which revs metabolism - often with a racing heart, shakiness, and heat intolerance. Undiagnosed diabetes, where sugar spills out in urine - watch for big thirst and frequent peeing. Depression, which flattens appetite, and medication side effects. Gut problems like celiac or inflammatory bowel disease, where food is not absorbed - pair weight loss with diarrhea or belly pain. And the serious end of the list: cancer, which is why unexplained weight loss is never waved off, especially over 50 or with fatigue, night sweats, or blood anywhere it should not be. The workup is routine: history, exam, and basic blood tests - thyroid, blood sugar, blood counts, inflammation markers - with imaging only if something points. Most causes turn out manageable, and the earlier you bring it in, the more options sit on the table. Pymander is a free AI doctor, 24/7 by text. Tell it how much, how fast, and what else has changed, and it can help you prep for the visit.