How long are your intestines?
An adult's intestines are about 7 to 8 meters long in total. The small intestine makes up most of that, at roughly 6 meters, while the large intestine is about 1.5 meters.
The small intestine is long but narrow, about 2.5 centimeters wide. It has three parts: the duodenum, the jejunum and the ileum. This is where most digestion and nutrient absorption take place. Measurements vary, and some studies of living people suggest it is shorter than older measurements made after death, when muscles relax.
The large intestine, or colon, is shorter but wider, about 6 to 7 centimeters across. It absorbs water and salts from food leftovers and turns them into solid waste. It is also home to trillions of bacteria that help break down fiber, make some vitamins and support the immune system.
A huge surface area
The inside of the small intestine is covered with folds and tiny finger-like projections called villi, which are themselves covered in even smaller microvilli. Together they greatly increase the area available for absorbing nutrients. Recent estimates put the inner surface of the whole gut at about 30 square meters, roughly half a badminton court.
Did You Know?
Food usually takes about 24 to 72 hours to travel through the whole digestive system, depending on what you eat and other factors.
This answer is general information, not medical advice. For a personal health question, talk to a doctor.