Unexplained Weight Loss

What is unexplained weight loss?

Unexplained weight loss is weight you have lost without trying to lose it.

Your weight can change, depending on how much you eat and exercise. However, if you have lost more than 10 pounds in the past few weeks or months without trying to diet, you should see your healthcare provider. The weight loss may be a sign of illness.

How does it occur?

Unexplained weight loss can be caused by:

• poor appetite
• decreased absorption of food, which means you are not digesting food properly
• a loss of nutrients
• high demand by the body for energy (calories).

A poor appetite can be caused by conditions such as:

• dentures that don’t fit well or pain in the teeth or mouth
• psychological problems that affect your eating habits (such as anorexia nervosa and bulimia)
• depression or anxiety
• drugs, such as digitalis and cancer drugs
• drug abuse, for example, abuse of amphetamines
• a high level of calcium in the blood
• a low level of potassium in the blood
• alcohol abuse
• viral hepatitis (an infection of the liver)
• heart failure
• cancer.

Decreased absorption of your food by your stomach or intestines can be caused by:

• gallbladder problems
• your body not making enough digestion enzymes
• previous stomach or intestinal surgery
• problems with the small intestine
• parasite infections, such as Giardia, which you can get by drinking water from contaminated streams or from working in a day care center
• injury or inflammation of the pancreas (the gland which sits behind the stomach and makes digestive enzymes and insulin)
• some drugs that may cause the bowel to empty too fast, such as cholestyramine (for cholesterol problems) and laxatives (for constipation).

Loss of nutrients can be caused by:

• diabetes when blood sugar is not in good control
• frequent diarrhea
• frequent or long-lasting vomiting
• kidney disease.

A high demand for energy can be caused by:

• an overactive thyroid gland making too much thyroid hormone, which speeds up the body's metabolism (a problem called hyperthyroidism)
• fever
• hyperactivity
• emotional states that cause increased physical activity, such as mania or bipolar disease
• amphetamine or other drug abuse
• cancer.

How is it diagnosed?

To try to find why you are losing weight, your healthcare provider will ask about your medical history and any other symptoms you may be having. He or she will examine you. In addition, you may have some blood tests. Depending on how much weight you have lost and blood test results, you may also have urine tests, a chest X-ray, and an abdominal ultrasound scan.

How is it treated?

First your healthcare provider will work to find and correct the underlying problem. Then your provider will also help you with your symptoms. Here are some examples of treatment:

• For anorexia, your healthcare provider may prescribe counseling and medicine.
• For poor appetite, your provider may suggest eating small, frequent meals. Eating more of your favorite foods may help. Eating more protein may also be important.
• For poor appetite due to nausea, your provider may suggest eating small, frequent meals, especially at times when nausea is milder. You may need anti-nausea medicine.
• For poor appetite caused by depression, your provider may suggest counseling and antidepressant medicine.
• For decreased absorption caused by problems with your pancreas, your provider may prescribe pancreatic enzyme preparations.
• For infections, your provider may prescribe medicine, such as antibiotics.
• For loss of nutrients, your provider may prescribe fat-soluble vitamins A, D, and K. Your provider may give you medicine to help stop severe diarrhea and vomiting while your provider tries to find the cause of the diarrhea.

How can I take care of myself?

To help take care of yourself, follow your healthcare provider's instructions. If you think you are losing weight, weigh yourself every week. If you lose 10 pounds or more in less than 6 months, without trying, and without a known illness to explain it, tell your healthcare provider. If you seem to be losing weight faster than that, see your provider right away.