Digestive Health Celiac Disease How the Intestinal Villi Help With Digestion These little "fingers" do the hard work of digestion By Nancy Lapid Nancy Lapid LinkedIn Twitter Nancy Ehrlich Lapid is an expert on celiac disease and serves as the Editor-in-Charge at Reuters Health. Learn about our editorial process Updated on September 24, 2020 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Robert Burakoff, MD, MPH Medically reviewed by Robert Burakoff, MD, MPH LinkedIn Robert Burakoff, MD, MPH, is board-certified in gastroentrology. He is the vice chair for ambulatory services for the department of medicine at Weill Cornell Medical College in New York, where he is also a professor. He was the founding editor and co-editor in chief of Inflammatory Bowel Diseases. Learn about our Medical Expert Board Print Intestinal villi are tiny, finger-like projections made up of cells that line the entire length of your small intestine. Your villi (villus is the singular, villi is the plural) absorb nutrients from the food you eat and then shuttle those nutrients into your bloodstream so they can travel where they're needed. If you don't have functioning intestinal villi, you can become malnourished or even starve, regardless of how much food you eat, because your body simply isn't able to absorb and make use of that food. Science Picture Co/Getty Images How Big Are Your Intestinal Villi? Your villi are really tiny—each one is no more than about 1.6 millimeters long and may be as short as 0.5 millimeters long. For comparison, 1.6 millimeters is the width of the ink line produced by the tip of a fine ballpoint pen, or the width of delicate wire used to make expensive jewelry, while 0.5 millimeters obviously is even smaller. Your villi alternate with depressions called crypts, where your small intestine actually manufactures the cells that form the villi and other parts of the intestinal lining. These crypts, when healthy, are about one-third to one-fifth as long as your villi. While individually the villi and crypts are obviously pretty miniature by themselves, together they provide a huge amount of surface area for nutrients to be absorbed into your bloodstream—almost the surface area of an entire football field, given that your small intestine itself is about 23 feet long. Conditions That Can Damage Villi There are several different medical conditions that can cause damage to your intestinal villi. In celiac disease, consumption of the protein gluten (found in the grains wheat, barley, and rye) triggers your immune system to attack your intestinal villi and wear them down (a process called villous atrophy). Many people with celiac disease have vitamin and mineral deficiencies when they're first diagnosed because their intestinal villi are damaged. Inflammatory bowel disease, which includes Crohn's disease, also can cause your villi to erode, as can lymphoma and certain infections, such as an infection involving the parasite Giardia. Some medications can cause damage to your intestinal villi, as well. These include Benicar (generic name: olmesartan), a blood pressure medicine, and some over-the-counter pain medications, such as aspirin and ibuprofen. Fortunately, in these cases, discontinuing the medication should result in your villi growing back. Was this page helpful? Thanks for your feedback! Following a gluten-free diet can be challenging. We're here to help. Sign up and receive our free recipe guide for delicious gluten-free meals! Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 4 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. Ensari A, Marsh MN. Exploring the villus. Gastroenterol Hepatol Bed Bench. 2018;11(3):181–190. Kupfer SS. Making Sense of Marsh. Impact: A Publication of the University of Chicago Celiac Disease Center. Fall 2009. DeGaetani M et al. Villous Atrophy and Negative Celiac Serology: A Diagnostic and Therapeutic Dilemma. American Journal of Gastroenterology. 2013 May;108(5):647-53. doi:10.1038/ajg.2013.45 Umar S. Intestinal stem cells. Curr Gastroenterol Rep. 2010;12(5):340–348. doi:10.1007/s11894-010-0130-3