What You Need to Know About Digestion and Waste

What You Need to Know About Digestion and Waste

In the middle of the interview, the conference room door opened and an energetic staff member joined us. He looked over my resume and said, “Oh, you must be the poop girl!”

The poop girl! I can't say I was offended because it actually gives insight into one of my favorite topics. Being a dietitian and working in the healthcare industry teaches you to see poop in a new light. In fact, one of the questions I always asked my patients relates to their bowel patterns. You'd be surprised how much you can learn about someone's diet and health by the frequency and consistency of their poop!

Let's think about it from a scientific standpoint: your gastrointestinal tract goes from your mouth to your anus and allows your body to utilize food and liquids for nourishment. What comes out at the end can tell you how your body absorbs certain nutrients, if you're dehydrated, if you have an adequate amount of nutrients, or if there is something a doctor should look into.


Average intestinal transit time (how long it takes for your food to become waste) is about 40-45 hours. So what is the normal amount of times you should be going? This is a tricky question because bowel pattern is very individualized. There is really no normal amount; it's more about what's normal for you individually. If you go once a day, three times a day, or once every three days, then that is your norm. Problems arise when this pattern begins to change. That is when some investigative work comes into play.


Constipation occurs when you are off your schedule and not going as frequently. The National Digestive Diseases Information Clearinghouse (NIDDC) defines constipation as "having a bowel movement fewer than three times per week." Constipation is most frequently caused by a decreased intake of fibrous foods, dehydration, pain medication, loss of appetite, physical inactivity, stress, pregnancy, and aging (as you age, your digestive motility actually slows down. No wonder prunes are so popular among seniors!)


Having loose, frequent and watery stools. The NDDIC defines diarrhea as "passing loose stools more than three times per day." Diarrhea is most frequently caused by bacterial infection (this is common in the hospital, as the bacteria C.diff is transmitted via contact), drastic increase in fiber in your diet, intestinal disorders (celiac, crohn's, irritable bowel) and eating a food you're allergic too.


Red: beets, foods made with red food dye (popsicles, kool-aid); if you see streaks of red it could be blood from a possible hemorrhoid or something more serious; If you see anything you think may be blood, call your doctor.

Very Dark: iron supplements, Multi-vitamin with iron, drinking red wine the night before, eating a lot of salt, possible upper-intestinal bleeding; call your doctor.

Yellow: can be caused by Giardia, a bacterial infection - call your doctor.

White/Pale: after drinking Barium Sulfate, which is often given to people receiving an x-ray of their GI tract; can also potentially indicate a problem with the gallbladder or liver - call your doctor.


Greasy and Floating: can indicate your body is having problems digesting certain foods, especially fats.

Corn: I actually received a text message from a friend once asking me, "Why is it when I eat corn, it comes out in my poop?" I had to include this in the post because many people have this question. Each kernel of corn is encased in fibrous cellulose. The human body is not able to break down cellulose, so this is passed through our intestine completely unchanged. The inner kernel will be broken down as it is comprised of starch, but the outer coat will remain the same.

Bowel movements are incredibly taboo in our society, but it is important to be connected with your body and understand what it is telling you. We have become obsessed with the quick fix and use medication to solve everything. I am not anti-medication, in fact, I think the advancement our society has made in medicine is incredible - we just need to take time to listen to what our bodies have to say because you never know what you might learn!

Registered Dietitian, Certified Specialist in Sports Dietetics

Comment by zeni1949
April 16, 2014
Am just learning combos, I do alot of smoothies cuzof my gastroparesis. If i dont eat right i keep a stomach ache. I also need to get enough protein. I also need to have simple receipes.
Comment by fotogal
July 20, 2013
Reply by zeni1949
April 16, 2014
Every other day is good. If you go 3 days yu are running the risk of impaction and that would not be a pretty picture. Get some miralax at pharmacy and take every day
Everyone is different, some people's bodies work differently than others. The definition of constipation is having a bowel movement fewer than 3 times per week. Having a bowel movement every 3 days is on the longer side of frequency but still falls within the average or normal side of things.
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