Unexplained Weight Loss

What is unexplained weight loss?

Unexplained weight loss is a noticeable drop in body weight when you’re not trying to lose weight. You’re not on a calorie-limited diet. In fact, you haven’t made changes to what or how much you’re eating. And you haven’t become more active recently.

How much unexplained weight loss is concerning?

Unexplained weight loss is concerning if you lose more than 5% of your body weight or 10 pounds over six to 12 months, especially if you’re over age 65. Most people gain and lose a little weight from day to day, but these changes tend to stay within a five-pound range. However, if you’ve lost more than that without trying, there might be something else going on.

Why is unexplained weight loss a red flag?

Unexplained weight loss is a red flag because it’s a common symptom of many serious illnesses. These diseases often get worse (progress) in stages. Some diseases — like diabetes or Addison’s disease — can progress quickly. Others — like cancer — may progress more slowly. Seek medical care as soon as you notice that you’ve lost 10 pounds or more than 5% of your body weight without trying to. This will give you the best chance of recovery.

What are the possible causes of unexpected weight loss?

Several health conditions can lead to unexplained weight loss. Some conditions reduce your appetite, while others prevent your body from absorbing calories, or increase the rate at which you burn calories.

Possible causes of unexpected weight loss include:

• Addison’s disease: This can cause unintentional weight loss because low levels of cortisol and aldosterone affect your metabolism. Other symptoms include chronic diarrhea, loss of appetite and nausea and vomiting.
• AIDS: Late-stage AIDS often leads to rapid weight loss due to changes in metabolism and diarrhea.
• Cancer: In cancer, changes in metabolism or appetite can lead to unexplained weight loss.
• Celiac disease: Some people with celiac disease lose weight because their intestines can’t absorb all the nutrients from food. Celiac symptoms also include diarrhea and vomiting.
• Crohn’s disease: This inflammation of your bowels or colon can make you lose your appetite and lead to chronic diarrhea.
• Dementia: People with advanced dementia can experience problems that lead to weight loss, like dental problems, trouble swallowing (dysphagia), forgetting to eat regularly and loss of appetite.
• Dental health issues: If you have trouble chewing, you may eat less than your body needs. Cavities, gum disease, temporomandibular joint (TMJ) disorders and toothaches can lead to unexplained weight loss.
• Diabetes: When your cells don’t have enough glucose, your body starts burning muscle and fat cells for energy. This can happen if you have undiagnosed diabetes, or if your medications aren’t managing your symptoms well.
• Eating disorders: Unexplained weight loss may be an early symptom of undiagnosed eating disorders like anorexia nervosa or bulimia nervosa.
• Heart failure: This can cause weight loss, especially in the later stages.
• Hyperthyroidism: This condition speeds up your metabolism and can lead to weight loss.
• Mental health conditions: You may have appetite changes with depression and anxiety, like little to no desire to eat.
• Medications: Sometimes, medications can cause issues such as altered taste or smell, decreased desire to eat, dry mouth, issues with swallowing, or nausea and vomiting that can contribute to weight loss over time.
• Parasitic infection: The diarrhea and vomiting from parasitic infections can lead to weight loss.
• Pancreatitis: If you have pancreatitis that doesn’t go away and gets worse over time (chronic), you may lose your appetite.
• Parkinson’s disease: Weight loss may occur because of other Parkinson’s disease symptoms, including loss of smell (anosmia), depression, trouble swallowing, loss of appetite, nausea and trouble feeding yourself due to lack of muscle control.
• Peptic ulcer: Symptoms of loss of appetite and nausea and vomiting can lead to weight loss.
• Prescription medications: Some medications cause weight loss as a side effect.
• Ulcerative colitis: Symptoms of ulcerative colitis like diarrhea, nausea and loss of appetite can lead to weight loss.
• Substance use disorder: Using substances like drugs and alcohol can change your appetite, lead to nausea and vomiting, and eventually may cause liver damage.

What tests are done for unexplained weight loss?

A healthcare provider may order specific medical tests based on your symptoms, family history and other factors. For example, if you have symptoms of a peptic ulcer, your provider may recommend an upper endoscopy.

Other tests may include:

• Blood tests: Your blood can show signs of certain health conditions like diabetes, celiac disease and infections. It can also give your provider information about how your metabolism, thyroid and adrenal glands are working.
• Cancer screening tests: If your provider wants to rule out cancer, you may need screening or imaging tests. For example, a colonoscopy can detect colorectal cancer.
• Imaging tests: Tests like an MRI (magnetic resonance imaging) or CT scan (computed tomography scan) can provide detailed images of your organs, like your brain, heart, lungs and abdominal organs. You may need one of these tests if your provider wants to rule out tumors or diseases that may be visible on these scans.
• Urine test: A urinalysis can provide information about your kidneys and bladder, including certain health conditions and infections.

How is unexplained weight loss treated?

Your treatment for unexplained weight loss depends on what’s causing it. For example, if you have a toothache, you may need to see a dentist. If the cause is a peptic ulcer, your provider may treat it with antibiotics. People with celiac disease must avoid all gluten.

What can I do at home to treat unexplained weight loss?

If you’re losing weight and don’t know why, don’t try to treat it at home. See a provider to find out the cause so you can receive the treatment you need.

Can unexplained weight loss be prevented?

Many of the conditions that lead to unexplained weight loss can’t be prevented. But there are some steps you can take to help prevent some of them, including:

• See your primary care provider for an annual physical exam.
• Get poked and checked! Be sure that you receive all recommended vaccines and cancer screenings.
• Take prescription medications as instructed. Reach out to your healthcare provider if you experience any side effects, including changes in appetite or weight after starting a new medication.
• Take good care of your teeth and gums. Brush your at least twice daily, floss every day and see your dentist for a cleaning and checkup as often as they recommend.
• Avoid substance use, and if you drink, do so in moderation.

When should I see my provider about unintentional weight loss?

Always see a healthcare provider if you lose weight without trying. Unexplained weight loss is often a sign of a health condition that requires treatment.

A note from Cleveland Clinic

Losing weight unexpectedly may seem like a good thing, so you might be tempted to ignore it. But don’t let this symptom go. You might need important medical care — and in most cases, the cause is manageable with treatment.

Contact your healthcare provider and discuss your symptoms and health history. You may need one or more medical tests to get a diagnosis. After your provider finds the cause, they’ll work with you to determine the best treatment. Treating the underlying condition causing the weight loss can help you regain weight and start feeling better.