How Much Does Poop Weigh in Your Body?

Ask a Doctor

When I’m at the gym and weigh myself, I always wonder if I’m getting an accurate weight. Like, what about water weight? Or like, if you ate food recently and it hasn’t left your body yet. I want to be able to subtract that (if only just to lie to myself about my weight, haha). How much does poop weigh in your body?

Doctor’s Response

In the book The Truth About Poop, author Susan E. Goodman states that people produce one ounce of poop for each 12 pounds of their body weight. This means the more you weigh, the heavier your poop will be.

According to the Centers for Disease Control (CDC) the average man in the U.S. weighs 195.7 pounds, and the average woman weighs 168.5 pounds. This means a man of average weight produces about 1 pound of poop and a woman of average weight produces about 14 ounces of poop per day, contained in your large intestine. The large intestine forms an upside down U over the coiled small intestine. It begins at the lower right-hand side of the body and ends on the lower left-hand side. The large intestine is about 5-6 feet long. It has three parts: the cecum, the colon, and the rectum. The cecum is a pouch at the beginning of the large intestine. This area allows food to pass from the small intestine to the large intestine. The colon is where fluids and salts are absorbed and extends from the cecum to the rectum. The last part of the large intestine is the rectum, which is where feces (waste material) is stored before leaving the body through the anus.

The main job of the large intestine is to remove water and salts (electrolytes) from the undigested material and to form solid waste that can be excreted. Bacteria in the large intestine help to break down the undigested materials. The remaining contents of the large intestine are moved toward the rectum, where feces are stored until they leave the body through the anus as a bowel movement.

The weight of your poop comes from the content of water, fiber, and bacteria present in the stool. Water makes up about 75% of feces and stool weight increases when more fiber is consumed, because fiber holds a lot of water.

Sandeep Mukherjee, MD, MB, BCh coauthored this article. REFERENCES:

Centers for Disease Control and Prevention. Body Measurements. 3 May 2017. 14 November 2018 .

Goodman, Susan E. The Truth About Poop. New York: Puffin Books, 2007.

Hill, Karen. How Much Poop Does an Adult Human Produce Each Day Per Pound of Food Eaten and What Is Poop Made of? 14 November 2018 .

John , Cummings H, et al. Fecal Weight, Colon Cancer Risk, and Dietary Intake of Nonstarch Polysaccharides (Dietary Fiber). 1992. Gastroenterology Journal. 14 November 2018 .