Causes of Rapid Weight Loss

Rapid weight loss can indicate a number of potentially serious health conditions, including digestive disorders, certain forms of cancer and diabetes. In many cases, your weight and wellness will return to a healthy level once the disorder is treated. If your weight drops quickly for no apparent reason, seek prompt medical guidance.

Crohn’s Disease

Crohn’s disease is an inflammatory bowel disease that causes inflammation and ulcers in the lining of the large intestine (colon). According to the National Digestive Diseases Information Clearinghouse, weight loss is one of the most common symptoms of the disorder. Such weight loss may be substantial and occur quickly. Additional symptoms of Crohn’s disease may include abdominal pain or bloating, diarrhea, arthritis, rectal bleeding or skin problems. When diarrhea intensifies, nutrient malabsorption commonly results. During severe episodes, people with Crohn’s disease may lose excessive amounts of weight, regardless of how much food they consume. Treatment for Crohn’s disease may include dietary lifestyle changes, medications, nutritional supplementation or surgery. No known cure exists for Crohn’s disease, but with proper care, long-term remission is possible.


Rapid weight loss may occur as a result of cancer or cancer treatments, such as chemotherapy. According to the American Cancer Society, most people diagnosed with cancer will experience weight loss at some point during the course of their illness and unintentional weight loss of 10 lbs. or more may occur as the first apparent cancer symptom. Rapid weight loss is most common in pancreatic, stomach, esophageal or lung cancer. People who experience vomiting or diarrhea in affiliation with cancer, chemotherapy or radiation treatment may also encounter rapid weight loss. Since nutritional wellness supports a person’s strength and ability to recovery from diseases such as cancer, discuss your weight loss symptoms and concerns with your doctor.


Diabetes causes excess sugar (glucose) build-up in the blood. As a result, the kidneys flush fluid containing glucose from the body through frequent urination. According to the Mayo Clinic, the more a person with diabetes drinks, the more fluids are flushed, resulting not only in urine-loss, but calorie loss as well. Particularly in the case of type I diabetes, such fluid loss is likely to result in rapid weight reduction. Left untreated, diabetes can lead to permanent damage in the eye as well as further blood sugar and health complications. Diabetes is manageable, however. If you suspect diabetes as the cause of your rapid weight loss, seek guidance and testing from your doctor. If you experience dry mouth or difficulty breathing in addition to rapid weight loss, seek immediate medical attention as such symptoms may indicate a life-threatening condition known as a diabetic coma.

About this Author

August J. McLaughlin is a certified nutritionist and health writer with more than nine years of professional experience. Her work has been featured in various magazines such as “Healthy Aging,” “CitySmart,” “IAmThatGirl” and “ULM.” She holds specializations in eating disorders, healthy weight management and sports nutrition. She is currently completing her second cookbook and Weight Limit – a series of body image/nutrition-related PSAs.