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Unintentional Weight Loss

Unintentional weight loss is when you lose weight without dieting or increasing physical activity. It may occur following a loss of appetite or when you’re consuming the same amount of calories as usual. Either way, it’s usually a cause for concern.

Unintentional weight loss can be extremely distressing, particularly when you lose a relatively significant amount and don’t know why. Unintentional weight loss could be a sign of serious illness or disease, or it could be something as minor as a stomach virus.

Unintentional weight loss is most prevalent in people with pre-existing medical conditions. Some people who experience this symptom suffer from a variety of diseases including cancer, AIDS, and depression.

What Causes Unintentional Weight Loss?

Unintentional weight loss is often the result of an underlying chronic medical condition. However, short-term illnesses such as influenza or the common cold can also cause weight loss due to abdominal discomfort.

Common causes of unintentional weight loss include depression, diarrhea, oral ulcers, and viral infections, such as the common cold, that can affect appetite.

Other, less common causes of unintentional weight loss include cancer, hyperthyroidism (overactive thyroid gland), abdominal infection, gastroenteritis, dementia, celiac disease, and HIV or AIDS.

Long periods of weight loss can lead to malnutrition. Malnutrition occurs when you aren’t consuming a proper amount of nutrients. This can be especially true for those with a digestive disorder such as celiac disease, which affects how the body absorbs nutrients.

What Are the Symptoms of Unintentional Weight Loss?

Depending on what caused the weight loss, symptoms vary widely. You may notice a change in the way your clothes fit, or in the shape of your face, since that is an area where many people can see initial weight loss effects. However, some people are unaware that they’ve lost weight until they weigh themselves.

Unintentional weight loss due to an illness may occur along with fever, loss of appetite, abdominal discomfort or pain, diarrhea, or constipation.

Children who have unintentional weight loss may also have changes in appetite, fussiness over certain foods, physically smaller stature (if over the long term), abdominal pain, or fever.

Certain medications can cause unintentional weight loss as a side effect. If you’re on any medication and experience noticeable weight loss, consult with your doctor.

How Is Unintentional Weight Loss Diagnosed?

Try to keep track of your weight loss. Note when the weight loss started. Also, make a note of any other symptoms you experienced around the time of the weight loss. This will give your doctor useful information that can help in making a diagnosis.

Unintentional weight loss is a symptom of several conditions. Your doctor must go over your symptoms and any recent lifestyle changes you’ve made to know exactly what’s causing the weight loss.

Your doctor may ask the following questions: Have you changed your diet? Have you had a recent illness? Have you recently traveled out of the country? Are you less energetic than usual? Have you had any digestive problems, such as diarrhea or constipation? Have you started taking any new medications?

If your doctor feels that your diet or a digestive disorder is to blame, they may do a nutritional assessment. This may consist of a blood test that shows levels of specific vitamins and minerals. The results of this test will determine if you’re deficient in any of these or if you have anemia.

Anemia occurs when your level of red blood cells is lower than usual. Iron deficiency or deficiency in a specific B vitamin can cause anemia.

Blood tests can also determine if a hormonal condition is to blame.

What Are the Treatment Options for Unintentional Weight Loss?

If you have a nutritional deficiency, your doctor may refer you to a dietitian or devise a diet plan that helps to correct the deficiency. A deficiency due to a digestive disorder, such as inflammatory bowel disease, may require a specialized diet during times of inflammation to help you get the nutrients you need. This may include taking over-the-counter supplements.

Your doctor will likely prescribe medication if a hormonal disorder is causing the unintentional weight loss.

You can correct unintentional weight loss due to general illnesses such as influenza, the common cold, or food poisoning with bed rest, an increase in fluids, and medications used to settle the stomach, and by getting back on your normal diet when you are feeling better.

If your doctor suspects that your unintentional weight loss may be due to a more serious illness, such as cancer, you may undergo some tests to get more information. 

Content licensed from:

Written by: April Kahn
Medically reviewed on: Mar 03, 2016: Peggy Pletcher, MS, RD, LD, CDE

This feature is for informational purposes only and should not be used to replace the care and information received from your health care provider. Please consult a health care professional with any health concerns you may have.
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