But one gastroenterologist says that your bowel movements can be an important clue to the state of your digestive health.
Dr Anish Sheth - otherwise known as Dr Stool - and Josh Richman outline all the things you can learn from examining your faeces in "What's Your Poo Telling You?", a book that uses jokes and trivia as a way to get people comfortable with talking about gastrointestinal health.
"Of course there's a humorous side to the subject of poo," said Sheth, a gastroenterology fellow at Yale University. "But what isn't as well known is that you can learn about your health by looking in the bowl."
The book comes with a serious message about the importance of preventing colon cancer, Sheth said. People may have some embarrassment when they first pick up the book, he said, but making health the focus of taboo topics makes it easier to discuss them. "I think that's a safe place."
The increasing availability of information online is breaking down taboos about previously undiscussed personal health topics, Sheth said. "Patients are coming to the table with a lot more information about particular conditions or concerns they may have."
Discussions of bowel health in popular culture also help open up discourse, he said. Oprah Winfrey recently devoted an episode of her talk show to discussing gastrointestinal health with Dr Mehmet Oz. "The Fiber 35 Diet" - a book advocating a high-fibre diet, along with cleansing and detox, for weight loss - hit the New York Times bestsellers list, and a new book called "The 'Regular' Gourmet Everyday: Sumptuous Recipes for the GastroAmerican Cancer Society Intestinally Challenged", by author Danielle Svetcov, will soon be released. And last year, the hospital sitcom Scrubs devoted a song to bowel movements - "Everything Comes Down to Poo" - in a musical episode.
So what can your bowel movements reveal?
A Floater is usually the result of too many burritos, but if it comes accompanied by a particularly bad smell and the presence of grease - an indication of fat in the stool - that can be a sign of underlying GI problems, usually related to the liver or pancreas and the body's ability to digest fat.
Thin stools - The Snake - are probably just a sign that you're straining too hard and causing your sphincter to contract, but when seen progressively over a longer period of time, they might indicate a colonic blockage due to rectal cancer.
Variations in stool colour are expected, but persistent changes can be an indication of a health problem: green stools can indicate a gastrointestinal infection, while white or grey stools may be the result of a bile duct blockage or liver disease.
Most serious of all is what Sheth and Richman term Rambo Poo. The appearance of blood in the stool is often an indication of gastrointestinal bleeding, Sheth said. Blood can be the result of something relatively minor, like haemorrhoids or diverticulosis. But it could also be the result of colon cancer, and the book advises anyone who sees blood in their stool to visit a doctor.
Sheth pointed out that many people may not realise that black stool can indicate blood as well. GI bleeding can develop gradually over time, he said, so paying attention to bowel movements can help to catch it - and its cause - early on. (To that end, he and Richman are releasing a second book, "The Poo Log", this spring.)
No perfect bowel movement
But the book is not meant to be alarmist. There is no perfect bowel movement, Sheth said, and regularity can be defined as emptying your bowels anywhere from three times a day to three times a week. The average weight of a day's worth of stool is 450 g, but day-to-day variations are normal based on factors such as diet and stress levels.
Serious issues aside, good bowel movements can affect how you feel each day, Sheth said. Compare what the book describes as Poo-phoria - where the passing of a large stool causes the rectum to distend and the vagus nerve to fire, increasing blood flow to the brain - to the unpleasant experience of a Log Jam.
"Frankly," Sheth said, "it is no fun to be constipated."
The best way to prevent constipation - as well as more serious GI problems such as colon cancer - is to include a lot of fibre in your diet, Sheth advised. "In some ways the book looks at fibre as a panacea for GI disease, and in some ways it's not too far from the truth." The recommended daily fibre intake is 25 to 35 g a day, he said, but the average American eats less than 10 grams. Populations with a high-fibre diet have been shown to have lower incidences of colon cancer and haemorrhoids, he said.
"The benefits of taking in enough fibre range from just feeling great to having healthy bowel habits to preventing more serious complications down the line."
Fruits and vegetables are a good source of fibre, but even if we ate the recommended daily intake we'd still only have consumed half the amount of fibre we should, Sheth said. "The main thing we need to do is increase our consumption of whole grains," he said. As with other aspects of nutrition, it's important to find ways to eat better that you can stick with because they're easy to incorporate into your daily diet - Sheth suggests eating bran or oatmeal in the morning.
While some foods - including dairy, red meat and processed foods - are more constipating than others, they can usually be part of a healthy diet with no bowel issues as long as you're meeting your fibre requirements, Sheth said. "The issue is usually a deficiency in high-fibre foods, not an excess of low-fibre foods."
Fibre fights cancer
Meeting the fibre requirements can help to prevent colon cancer, a cancer that is often deadly, but highly preventable, and which can often be cured when caught early, Sheth said. According to the American Cancer Society, about 90 percent of people with colon cancer that is caught before it has spread to the lymph nodes or surrounding organs, hit the five-year survival mark, but only about 10 percent of those whose cancer has spread live for 5 years.
The American Cancer Society recommends that people over 50 should be regularly screened for colon polyps and cancer, and those with increased risk should begin screening earlier. But data released last year by the Centres for Disease Control and Prevention showed that while the number of people up-to-date with colon cancer screening has increased, it was still at only about 60 percent in 2006, lower than rates for other screening tests like mammograms.
"What's Your Poo Telling You?" is just another tool for people to use along with regular screening and information from their doctors, Sheth said. That resource is extended to the book's website, where readers can ask questions - recent examples include "What volume of faeces would you say an average American male (170 pound) would generate over his lifetime?" and "Is it possible for haemorrhoids to impede or affect poo evacuation?" - which Sheth will answer either via email or on the site itself. –
(Terri Coles/Reuters Health, updated February 2009)
A history of the toilet