Unexplained weight loss is a noticeable drop in body weight that occurs even if the person is not trying to lose weight. Unexplained weight loss can be a symptom of a serious illness, including cancer or diabetes. Treatment involves identifying the underlying cause of the 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.
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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.
Unexplained weight loss can be caused by conditions that range from mild to very serious. The causes can be physical or psychological, and include:
You should consult your physician if you have lost more than 5 percent of body weight or 10 pounds without trying in a period of 6 to 12 months. This is especially important if you have other symptoms, too.
To diagnose your weight loss, your doctor will give you a physical examination and ask you such questions as:
The answers to these questions will help your doctor determine if other tests might be needed, such as blood work and imaging scans (X-rays, etc.).
Unexplained weight loss is treated by identifying the underlying condition (the condition or illness that is causing the weight loss). If no underlying condition is identified right away, your doctor may recommend a wait-and-see approach, along with a special diet.
For instance, your doctor may recommend that you use nutrition shakes to get more calories, or add flavor enhancers to your food to improve the taste so that you eat more. You may be also be referred to a dietitian for advice and counseling.
Last reviewed by a Cleveland Clinic medical professional on 08/31/2018.
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