What is unexplained weight loss?

Unexplained weight loss is a noticeable drop in body weight that occurs even if the person is not trying to lose weight. The weight loss does not come about because of diet, exercise or lifestyle changes. Weight loss of 10 pounds or more, or five percent of body weight, over a period of 6 to 12 months is considered “unexplained.”

Unexplained weight loss can be a symptom of a serious condition or illness. For this reason, it is important to seek medical attention if you (or a family member) have weight loss that cannot be explained.

Who is at risk for unexplained weight loss?

Unexplained weight loss can occur in anyone. However, it is most common (and most serious) in people who are over the age of 65. Even unexplained weight loss of less than 5 percent of body weight or 10 pounds may be the sign of a serious condition in older people.

What are the causes of unexplained weight loss?

Unexplained weight loss can be caused by conditions that range from mild to very serious. The causes can be physical or psychological, and include:

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