I can understand how this topic on poop may seem a bit uncomfortable to some, but based on my experiences with patients and students, I’m going to tell you that many people have similar questions.
Heck, Dr. Oz did a whole episode on this topic a few years back.
In fact, I still remember when I was in school, when we were covering the digestive system module, a friend of mine asked our professor about bowel movement frequency. At the time, my friend was following the “Eat every 3 hours, 6 meals a day” plan. And he asked the professor “So, how often SHOULD we be having a bowel movement?”
Our professor paused for a moment and said, “Ideally after every meal.”
My friend then blurted out, “6 times a day?!”
Luckily, for my friend, this was one of the very few times my professor was incorrect.
What is Normal Bowel Frequency?
There have been studies that examine bowel frequency and disease risk, like colon cancer for example. There are even studies that look at bowel movement frequency and Parkinson’s disease.
This is because there’s the theory that the health status of the gut influences the health status of the brain (also known as the gut-brain connection).
Most studies have found that one bowel movement each day is about right. In some, one bowel movement every 2 to 3 days may be fine, as well. Unfortunately, when we look at some of the largest studies on this topic, their findings differ.
One large study performed in the U.S. found that those with 2 or more bowel movements each day did not have an increased risk for colon cancer when compared to those that experience 1 each day. However, a recently published Japanese study couldn’t replicate these results. They found that having a bowel movement once every 6 days or so had the highest risk for developing colon cancer.
So, it seems that, depending on the person, having anywhere from 3 bowel movements a day to 3 per week may be considered normal. So, luckily for my colleague back in school, our professor was incorrect: 6 times a day would NOT be considered normal!
What Determines Stool Frequency?
Now, what actually determines healthy poop frequency? So many factors — age, gender, hydration, medications, stress, diet of course, body weight, and physical activity to name a few. I’m not going to discuss specific disease states like Irritable Bowel Syndrome (IBS) or Inflammatory Bowel Disease (IBD) because that would need a separate episode on its own.
If we think about age for a moment, for those parents out there — even parents of baby animals — you probably have noticed that these young ones often have more frequent bowel movements when compared to adults, or even when compared to their older siblings. As we move from young adulthood into middle age and beyond, stool frequency also tends to decrease.
Do Men Have More Bowel Movements Than Women?
Women, on average, have fewer bowel movements than men. But that may just be because men eat a higher volume of food. Those that have a higher Body Mass Index may have more frequent bowel movements as well.
It seems that walking or jogging may lead to more frequent bowel movements. It’s believed that walking and jogging stimulate the colon to push its contents along a little more quickly (what healthcare practitioners call peristalsis).
Do Medications Cause Constipation?
As for medications, a strong pain reliever like a narcotic or anti-depressant may slow down peristalsis and lead to constipation.
When you take antibiotics, they may temporarily wipe out the good bacteria in your colon which can change the number of times you poop. You may experience diarrhea or constipation…it just depends.
This is because antibiotics are built to kill bacteria. They don’t know which ones are good or bad — they just kill all bacteria.
Stress can absolutely play a role, too. In some, stress stimulates peristalsis which causes more frequent bowel movements. In others, it can lead to constipation.
I wish I had more definitive answers. There are just so many variables that may influence how often you poop. When it comes to diet and maintaining stool frequency, the scientific community mostly agrees that staying adequately hydrated (drinking enough water so that your urine is a pale yellow color and getting 20 to 35 grams of dietary fiber each day (ideally from whole foods like fruits and vegetables) appear to be most important. Both of these will help keep the gut microbiome healthy which we agree definitely influences bowel frequency.