What do the bowels do?
Just like on a conveyor belt, everything you eat and drink goes through the intestines. The time needed for the food to pass through this conveyor belt and come out as a stool is called the transit time.
In the small intestine, the food is diluted with a few liters of water and enzymes are added for degrading foor into nutrients (proteins, fats and carbohydrates). The small intestine absorbs these nutrients into the blood.
Every day, after it’s digested in the small intestine, the colon processes several liters of diluted content consisting of water and indigestible matter. Indigestible substances are mainly fibers. The main task of the colon is to return all of the water back into the organism. In one day the colon can absorb five liters of water. The longer the content stays in the colon, the more water is reabsorbed. As more water is reabsorbed, the stool becomes smaller and harder.
How does content move through the intestines?
The wall of the intestines are composed of smooth muscle. These muscles alternately contract and relax, forming undulating movements which we call peristalsis. Peristalsis moves the content through the intestines.
The small intestine is a hard working organ. It constantly moves in a wave-like motion and absorbs nutrients. The small intestine performs peristalsis even when it is empty – then you can hear “rumbling” in the stomach.

The slower part of digestion. Contents pass through the colon within 24 – 70 hours.
The colon is a quiet and somewhat lazy organ. It slowly moves its content in order to absorb all the water. When the content passes too quickly through the colon, it doesn’t have time to absorb all the water, which results in diarrhea.
There are three types of wave-like motions in the colon. Low intensity waves that mix the contents in the intestines, but can not suppress it further. Medium intensity waves which suppress gases and liquids. There are about 100 of these per day. High intensity waves, which happen only six times a day. They suppress the contents of the long segment of the colon. The colon works quietly and is mostly silent, but sometimes the results of its work can be heard and smelled (passing wind). Between 10 pm and 6 am there are no undulating movements. The colon sleeps and rests, and in the morning it wakes and then the undulating movements are the strongest.
After eating, the stretched stomach signals the colon to prepare for the arrival of food. This is called the gastrocolic reflex and it enhances all of the three wave types. It lasts for about an hour after eating.
The main stimulus for the colon’s performance is the stretching of its wall due to contents piling up, which galvanizes medium intensity waves.
How often is it normal to have a stool?
This greatly varies from one person to the next. Digestion does not move at the same speeds for all of us. The time it takes for the food to pass through the digestive tract is called the transit time and it lasts from a few hours up to a few days. The passage through the small intestine takes a few hours. The passage through the colon is sluggish and takes 16 to 48 hours. Simply said, digestion is faster for some and slower for others.
Therefore, it is normal if someone has three stools per day, but also if someone has three stools per week.
Less than three stools per week is considered constipation.
Does the colon protect us or poison us?
Most people imagine the colon as a form of sewage filled with wastewater from which toxins that poison the body are reabsorbed.
Probably because of this misconception there are many methods of colon cleansing, aimed at improving health. But they result in deteriorating health.

There are 400 types of bacteria living in our colon.
It truly contains our waste. Nature has given us the best waste governing system. In our colon, there are more than 300 types of good bacteria that we have been in harmony with for thousands of years. Previously, we called them intestinal flora and today the popular name is microbiota. They are so important that any disorder to their condition has devastating effects on our health. These beneficial bacteria produce short chain fatty acids, rather than poisons. Short-chain fatty acids are food for the colonic mucosa since they cannot obtain food from the blood. In addition, the good bacteria inhibit the growth of bad bacteria. It could be compared to a maintained lawn where only grass grows. There are no weeds. Weeds grow when the grass is not maintained.
A type of bad bacteria would be Clostridium difficile. It does not attack constipated individuals but those who have taken antibiotics which destroyed the good bacteria. Sometimes these bad bacteria can be resistant to all forms of therapy. Then, the only thing that helps is administrating the feces of a healthy individual. Yes, you read that right. Someone else’s feces are transferred directly into the patient’s intestine via a probe. That way, good bacteria are injected and they stop the growth of the bad ones. This disease is called pseudomembranous colitis, a type of colon inflammation with frequent and severe diarrhea.
The colon and the good bacteria know how to manage our waste. Let us allow them to work unobstructed. In exchange, they require precious little – only our waste and body heat.
The purpose of intestinal bacteria:
- Immunity
- The intestinal flora is a physical barrier to the development of dangerous bacteria.
- Nutrition
- Intestinal flora produces short-chain fatty acids for the colon mucose’s nutrition. It participates in vitamin B and K synthesis and helps calcium and iron absorption.
- Obesity
New research has shown that intestinal flora plays a role in the regulation of body weight. The same food gives certain people more energy than others. The cause of that is intestinal bacteria, which differ in obese and skinny people.
Inflammation
Studies show that intestinal bacteria have a role in the onset of inflammatory bowel diseases (Crohn’s disease and ulcerative colitis).
Can constipation be dangerous?
In most cases, constipation is not dangerous. If constipation and straining during a bowel movement last for a longer period of time, hemorrhoids, anal fissures, or sluffing of the colon’s lining can occur.
Constipation is dangerous only if you have some of the alarming signs. These signs may indicate the presence of cancer or an inflammatory colonic disease. When they occur, you should consult a gastroenterologist. Further examination usually involves a colonoscopy.
Table 1. Alarming signs with constipation