What Causes Diarrhea and Loss of Appetite?

Diarrhea and loss of appetite are two common digestive complaints that can occur separately or together and are often indicative of another underlying health condition.

Diarrhea is characterized as watery, loose stools that are usually accompanied by an increased frequency and urgency in bowel movements.

Loss of appetite, referred to by healthcare providers as anorexia, is defined as a reduced desire to eat.

This article will explain the potential causes of diarrhea and a loss of appetite, as well as diagnosis and treatment options for these digestive issues.

Woman unhappily eating
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Related Symptoms

Both diarrhea and loss of appetite may present along with other symptoms.

Symptoms that may be associated with diarrhea include:

  • Fatigue
  • Nausea
  • Vomiting
  • Urgency and increased frequency of bowel movements
  • Unintentional weight loss
  • Malnutrition
  • Abdominal pain
  • Blood in stools

Symptoms that may be associated with loss of appetite include:

  • Unintentional weight loss
  • Weakness
  • Fatigue
  • Pain
  • Nausea
  • Vomiting
  • Constipation
  • Diarrhea
  • Changes in the ability to smell or taste

Causes of Diarrhea and Loss of Appetite

Diarrhea and a loss of appetite can be due to a number of causes.

Common causes of diarrhea include:

There are also numerous reasons for a loss of appetite. In elderly adults, a decrease in appetite can occur with no apparent physical cause.

Possible causes for a loss of appetite include:

Diagnosing the Issue

Diarrhea and a loss of appetite can be due to many causes. Your healthcare provider may use several tests to determine the underlying cause.

History and Physical Evaluation

During a history and physical exam, your healthcare provider will ask a series of questions, examine your body and take a number of measurements to determine your overall health.

This includes:

  • Checking vital signs like blood pressure, weight, and height
  • Asking about any additional symptoms you may be experiencing
  • Listening to your heart
  • Listening to your lungs
  • Taking your pulse
  • Examining your lymph nodes
  • Looking at your skin
  • Listen to and press on your abdomen

Dietary Recall

If your healthcare provider suspects that you may have a food intolerance or allergy that may be contributing to your diarrhea or loss of appetite, they may ask about what foods you have been eating.

Your healthcare provider may also ask you to exclude certain foods from your diet to see if your symptoms improve, or to keep a food diary for a few weeks to help identify any triggers.

Blood Tests

A blood test can be used to detect a number of underlying conditions like celiac disease, chronic liver disease, or hypothyroid. A blood test can also be useful for detecting low levels of vitamins that could indicate problems with nutrient absorption in the intestines.

Stool Samples

Your healthcare provider may take a sample of stool to be tested in a lab. This helps in detecting the presence of any abnormal bacteria or other infections in the digestive tract that may be causing symptoms like diarrhea or loss of appetite.

Treating Loss of Appetite and Diarrhea

Treatment for loss of appetite or diarrhea will depend on the underlying cause of the symptoms.

Medications like antibiotics may be used to treat infections, and other prescription medications may be used to treat or manage the symptoms of underlying health conditions like Crohn's disease.

There are also home remedies that are known to help with short-term diarrhea and loss of appetite.

To help with diarrhea, consider trying the following tips:

  • Drink at least one cup of clear liquid whenever you have a loose bowel movement
  • Drink eight to 10 glasses of clear fluid a day, ideally water
  • Instead of eating three big meals a day, eat smaller meals throughout the day
  • Eat foods high in potassium like potatoes with no skin, bananas, or fruit juice
  • Try eating salty foods like pretzels or soup
  • Ask your healthcare provider if you should consider taking a multivitamin or drinking sports drinks
  • Avoid eating fried foods
  • Avoid caffeine and alcohol
  • Avoid carbonated drinks
  • Limit dairy intake

To help with a loss of appetite, consider trying:

  • Eating regular meals and snacking throughout the day
  • Buying foods that are easy to prepare
  • Choosing foods that are high in nutrients, like vegetables and fruit
  • Keeping your fluids up, especially your water intake
  • If solid food doesn't appeal, try smoothies or soup with added protein powder
  • Exercising
  • Trying eating high-calorie foods like cheese, peanut butter, eggs, granola bars, and nuts
  • Eating your favorite foods any time of day

When to Seek Medical Attention

It's normal to experience diarrhea and/or loss of appetite for a few days, especially if you have or are recovering from a stomach bug or have been traveling. But if these issues persist for more than four days or worsen, consult your healthcare provider. They can help determine the underlying cause and direct you to the appropriate treatment.

Contact your healthcare provider if you have diarrhea that does not improve in five days or occurs with any of the following symptoms:

  • Nausea
  • Vomiting
  • Stools that smell unusual
  • Stools that are an unusual color
  • Bloody stools
  • Fever
  • Stomach pain

If you have a loss of appetite, call your healthcare provider if you also:

  • Feel nauseated
  • Haven't eaten at all for more than a day or longer
  • Haven't had a bowel movement in two days or more
  • Aren't urinating frequently
  • Have pain when eating
  • Have been vomiting for more than 24 hours
  • Are losing a lot of weight unintentionally
  • Think you may have an eating disorder


Diarrhea and loss of appetite can be caused by a number of factors including infections, underlying conditions or mental health concerns. Diarrhea and loss of appetite may be accompanied by other symptoms including nausea and weight loss. Treatment will depend on the underlying cause, but there are steps people can take at home to cope with diarrhea or a loss of appetite.

A Word From Verywell

Struggling with diarrhea or a loss of appetite can be distressing. Both conditions can be accompanied by symptoms like nausea and unintentional weight loss.

Help is available. Don't be afraid to reach out to your healthcare provider, who will be able to help you identify the underlying cause for your symptoms and offer treatment options.

Frequently Asked Questions

  • Can stress cause decreased appetite and diarrhea?

    A loss of appetite and diarrhea can both be caused by stress. These digestive complaints can also be caused by anxiety and depression.

  • Can not eating cause diarrhea?

    There are a number of things that can cause diarrhea. A sudden change in diet or stress may cause diarrhea as well as a lack of appetite. However, not eating has not been associated with causing diarrhea.

  • What should you eat when you have no appetite?

    Those with a lack of appetite should try and eat their favorite foods, even if this means eating lots of starchy foods like pasta and bread or eating breakfast foods for every meal.

    To get in enough calories, reach for foods that are high in protein and fat like steak, eggs, peanut butter, and cheese.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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