Definition

By Mayo Clinic Staff

Unexplained weight loss, or losing weight without trying — particularly if it's significant or ongoing — may be a sign of a medical disorder.

The point at which unexplained weight loss becomes a medical concern is not exact. But many health care providers agree that a medical evaluation is called for if you lose more than 5% of your weight in 6 to 12 months, especially if you're an older adult. For example, a 5% weight loss in someone who is 160 pounds (72 kilograms) is 8 pounds (3.6 kilograms). In someone who is 200 pounds (90 kilograms), it's 10 pounds (4.5 kilograms).

Your weight is affected by your calorie intake, activity level and overall health. Your ability to absorb nutrients from the food you eat also affects your weight. Economic and social factors also may play a role.

From Mayo Clinic to your inbox

Sign up for free and stay up to date on research advancements, health tips, current health topics, and expertise on managing health. Click here for an email preview.

We use the data you provide to deliver you the content you requested. To provide you with the most relevant and helpful information, we may combine your email and website data with other information we have about you. If you are a Mayo Clinic patient, we will only use your protected health information as outlined in our Notice of Privacy Practices. You may opt out of email communications at any time by clicking on the unsubscribe link in the email.

Aug. 17, 2022

See also

  1. 10 ways to avoid diabetes complications
  2. 6 tips to manage rheumatoid arthritis symptoms
  3. Acanthosis nigricans
  4. Achalasia
  5. Addison's disease
  6. Adenocarcinoma: How this type of cancer affects prognosis
  7. Adjuvant therapy for cancer
  8. Adrenal fatigue: What causes it?
  9. Amyloidosis
  10. Angina
  11. Anorexia nervosa
  12. Antidepressants and alcohol: What's the concern?
  13. Antidepressants and weight gain: What causes it?
  14. Antidepressants: Can they stop working?
  15. Antidepressants: Selecting one that's right for you
  16. Antidepressants: Side effects
  17. Antidepressants: Which cause the fewest sexual side effects?
  18. Artificial sweeteners: Any effect on blood sugar?
  19. Ascariasis
  20. Aspergillosis
  21. At-home colon cancer tests
  22. Atypical antidepressants
  23. B-cell lymphoma
  24. Bile reflux
  25. Binge-eating disorder
  26. Blood glucose meters
  27. Blood glucose monitors
  28. Blood sugar testing: Why, when and how
  29. Bone and joint problems associated with diabetes
  30. Bone cancer
  31. Burkitt lymphoma
  32. Caffeine: Does it affect blood sugar?
  33. Cancer blood tests
  34. Cancer pain: Relief is possible
  35. Cancer surgery
  36. Cancer survival rate
  37. Cancer survivors: Care for your body after treatment
  38. Cancer survivors: Late effects of cancer treatment
  39. Cancer survivors: Managing your emotions after cancer treatment
  40. Cancer treatment myths
  41. Cancer-related diarrhea
  42. Cancer-related fatigue
  43. Carcinoid tumors
  44. Celiac disease
  45. Chemotherapy side effects: A cause of heart disease?
  46. Chronic lymphocytic leukemia
  47. Churg-Strauss syndrome
  48. Cirrhosis
  49. Clinical depression: What does that mean?
  50. Colon cancer
  51. Colon Cancer Family Registry
  52. Colon cancer screening
  53. Colon cancer stool: What to look for and how to test at home
  54. Congenital adrenal hyperplasia
  55. Coronary artery spasm: Cause for concern?
  56. Crohn's Crisis
  57. Crohn's disease and the gut microbiome
  58. Curcumin: Can it slow cancer growth?
  59. Depression (major depressive disorder)
  60. Depression and anxiety: Can I have both?
  61. Depression in women: Understanding the gender gap
  62. Depression, anxiety and exercise
  63. Dermatomyositis
  64. Diabetes
  65. Diabetes and depression: Coping with the two conditions
  66. Diabetes and exercise: When to monitor your blood sugar
  67. Diabetes and heat
  68. Diabetes and liver
  69. Diabetes diet: Should I avoid sweet fruits?
  70. Diabetes foods: Can I substitute honey for sugar?
  71. Diabetes management: How lifestyle, daily routine affect blood sugar
  72. Diabetes treatment: Can cinnamon lower blood sugar?
  73. Diabetic Gastroparesis
  74. Diabetic neuropathy
  75. Diffuse large B-cell lymphoma
  76. Does stress make rheumatoid arthritis worse?
  77. Dr. Mark Truty (surgery, MN) better outcomes with chemo
  78. Drug addiction (substance use disorder)
  79. Early HIV symptoms: What are they?
  80. Eating disorder treatment: Know your options
  81. Eating disorders
  82. Eating during cancer treatment: Tips to make food tastier
  83. Esophageal cancer
  84. Ewing sarcoma
  85. Fatty liver disease (MASLD)
  86. Fatty liver disease (MASLD) diet
  87. Fecal transplant treatment of C. difficile at Mayo Clinic
  88. Fibromuscular dysplasia
  89. Floor of the mouth cancer
  90. Follicular lymphoma
  91. Gallbladder cancer
  92. Gallbladder polyps: Can they be cancerous?
  93. GI Stents
  94. Giant cell arteritis
  95. Giardia infection (giardiasis)
  96. Glycemic index: A helpful tool for diabetes?
  97. Grateful patient talks about his Mayo Clinic experience
  98. Graves' disease
  99. Hairy cell leukemia
  100. Heart cancer: Is there such a thing?
  101. Helicobacter pylori (H. pylori) infection
  102. Hepatocellular carcinoma (HCC)
  103. High-dose vitamin C: Can it kill cancer cells?
  104. Hilar cholangiocarcinoma
  105. Histoplasmosis
  106. HIV/AIDS
  107. Hodgkin lymphoma (Hodgkin disease)
  108. Hodgkin vs. non-Hodgkin lymphoma: What's the difference?
  109. How cancer spreads
  110. How do I reduce fatigue from rheumatoid arthritis?
  111. How to tell if a loved one is abusing opioids
  112. Hyperinsulinemia: Is it diabetes?
  113. Hyperthyroidism (overactive thyroid)
  114. Hypopituitarism
  115. Infographic: Cancer Clinical Trials Offer Many Benefits
  116. Infographic: Lung Cancer
  117. Infographic: Multiple Myeloma
  118. Infographic: Pancreatic Cancer: Minimally Invasive Surgery
  119. Infographic: Pancreatic Cancers-Whipple
  120. Infographic: Pancreatic Neuroendocrine Tumors
  121. Insulin and weight gain
  122. Intestinal ischemia
  123. Is depression a factor in rheumatoid arthritis?
  124. Is there a special diet for Crohn's disease?
  125. Kidney cancer
  126. Kidney Cancer
  127. Kidney cancer FAQs
  128. Kratom for opioid withdrawal
  129. Kratom: Unsafe and ineffective
  130. LADA
  131. Lead poisoning
  132. Leukemia
  133. Liver cancer
  134. Liver cancer FAQs
  135. Low blood counts
  136. Lung cancer
  137. Lymphoma
  138. Lymphoma FAQs
  139. Male depression: Understanding the issues
  140. Mantle cell lymphoma
  141. MAOIs and diet: Is it necessary to restrict tyramine?
  142. Marginal zone lymphoma
  143. Marijuana and depression
  144. Mayo Clinic Minute: Avoid opioids for chronic pain
  145. Mayo Clinic study reporting increased incidence of C. difficile infection
  146. Medications for type 2 diabetes
  147. Mesothelioma
  148. Mort Crim and Cancer
  149. Mouth sores caused by cancer treatment: How to cope
  150. Multiple myeloma
  151. Myths about cancer causes
  152. Natural remedies for depression: Are they effective?
  153. No appetite? How to get nutrition during cancer treatment
  154. Non-Hodgkin lymphoma
  155. Norovirus infection
  156. Opioid stewardship: What is it?
  157. Pain and depression: Is there a link?
  158. Pancreatic cancer
  159. Pancreatic Cancer Survivor
  160. Pancreatic neuroendocrine tumors
  161. Pancreatitis
  162. Peptic ulcer
  163. Peritoneal carcinomatosis
  164. Pheochromocytoma
  165. PICC line placement
  166. Pituitary tumors
  167. Prescription drug abuse
  168. Prostate cancer recurrence
  169. Protect your joints while housecleaning
  170. Pulmonary fibrosis
  171. Pyloric stenosis
  172. Reactive hypoglycemia: What can I do?
  173. Rectal cancer
  174. Recurrent breast cancer
  175. Rethinking Rheumatoid Arthritis
  176. Rheumatoid arthritis
  177. Rheumatoid arthritis
  178. Rheumatoid arthritis and exercise
  179. Rheumatoid arthritis: Can it affect the eyes?
  180. Rheumatoid arthritis: Can it affect the lungs?
  181. Rheumatoid arthritis: Does pregnancy affect symptoms?
  182. Ricin poisoning
  183. Salt craving: A symptom of Addison's disease?
  184. Seasonal affective disorder treatment: Choosing a light box
  185. Self-care for fatty liver disease (MASLD)
  186. Self-Image During Cancer
  187. Small cell, large cell cancer: What this means
  188. Stage 4 (metastatic) colon cancer
  189. Staying active with Crohn's disease
  190. Takayasu's arteritis
  191. Tapering off opioids: When and how
  192. Tapeworm infection
  193. Teen depression
  194. The dawn phenomenon: What can you do?
  195. Throat cancer
  196. Thyroid disease: Can it affect a person's mood?
  197. Thyroid nodules
  198. Tips to make your mornings easier
  199. Treatment-resistant depression
  200. Tuberculosis
  201. Tumor vs. cyst: What's the difference?
  202. Type 1 diabetes
  203. Type 1 diabetes FAQs
  204. Type 1 diabetes in children
  205. Type 2 diabetes
  206. Type 2 diabetes in children
  207. Types of diabetic neuropathy
  208. Typhoid fever
  209. Ulcerative colitis flare-ups: 5 tips to manage them
  210. Using insulin
  211. Valley fever
  212. Vasculitis
  213. Vegetarian diet: Can it help me control my diabetes?
  214. Vitamin B-12 and depression
  215. Vitamin deficiency anemia
  216. Vitamins and supplements for fatty liver disease (MASLD)
  217. What are opioids and why are they dangerous?
  218. What is cirrhosis? A Mayo Clinic expert explains
  219. What is Crohn's disease? A Mayo Clinic expert explains
  220. What is depression? A Mayo Clinic expert explains.
  221. What is kidney cancer? An expert explains
  222. What is lymphoma? An expert explains
  223. What is stomach cancer? A Mayo Clinic expert explains
  224. What is type 1 diabetes? A Mayo Clinic expert explains
  225. What is ulcerative colitis? A Mayo Clinic expert explains
  226. When cancer returns: How to cope with cancer recurrence
  227. Where can I learn more about living with Crohn's disease?
  228. Whipple's disease
  229. Zollinger-Ellison syndrome