Benjamin Franklin said the only two things certain in life are death and taxes. Let’s add another to the list—poop. That’s right, everyone poops. You may not talk about it very much, but your bowel movements have a lot to say about you.

What you see in the toilet bowl can tell you if you’re drinking enough water, getting enough fiber in your diet, or if you have food intolerances. And in some cases, it can be a red flag that you have an undiagnosed medical condition and should discuss with your doctor.

We know talking about your bathroom habits with a healthcare professional can feel awkward. But Janice Rafferty, MD, chief of colorectal surgery and medical director of surgical oncology services at The Christ Hospital Health Network, says it’s something you should do—especially if your bowel movements have changed.

“Just like you would pay attention to a headache, a changing mole, or chest pain, you should pay attention to what your body is telling you with your bowel movements,” she says. “Bowel movements are different for everyone. If you experience changes that linger for more than a few days, talk with your doctor. If something really is wrong, you’ll have more treatment options if you speak up sooner.”

So, what’s the scoop on poop?

Is your poop normal?

Your bowel movements and your microbiome are like a fingerprint. They are unique to you. But “normal poop” does have some general characteristics that most people share.

Healthy bowel movements should be:

• Brown (tan to dark coffee)

• Cylinder shaped

• Moderately firm

• Several inches long

It’s OK if you don’t go every day. Dr. Rafferty says at least three times a week is healthy. It’s also fine if you’re in the bathroom multiple times a day. And it shouldn’t hurt.

“The critical issue is that you shouldn’t spend more than about three minutes on the toilet,” says Sara Pulskamp, CNP, a Certified Nurse Practitioner with The Christ Hospital Physicians – Colon & Rectal Surgery. “Your waste should be fluffy and soft, and you shouldn’t need to push or strain. Having a bowel movement shouldn’t be work.” She adds that if you reference the Bristol Stool Scale displayed below, you want to trend toward the middle of the chart.

While brown is the most common color for bowel movements, that is not always the same for everyone. But you probably already know that’s not always the case. Dr. Rafferty says the color changes based on what you eat, if you’re taking medication or if you have an infection.

Here’s what you need to know about the hue of your number two:

• Black: If you’re taking an iron supplement, diarrhea medication that contains bismuth or an antibiotic, black stool is likely nothing to worry about. Flush it and forget it. Otherwise, it could mean you have bleeding in your gastrointestinal tract, and you need medical attention right away.

• Green: Green stool isn’t a big deal. Either food is moving too quickly through your digestive system, you ate a large serving of leafy green vegetables, or you recently ate something with artificial coloring.

• Red: Like black stool, red stool may be a red flag. If you’ve recently consumed a lot of red foods like beets, or juices with red dye, don’t worry. If not, red could be blood, and that’s a possible sign of colorectal cancer​ - so see your doctor as soon as possible.
  

• White: If your stool is white, your bile ducts may not be able to push the bile through. You could have an infection or a mass blocking your bile duct. Please​​ bring this to the attention of your GI doctor as soon as possible.

• Yellow: Cut back on fat in your diet if you have yellow, greasy bowel movements that float. Yellow stool could also mean you’re not absorbing enough nutrients due to illness or food intolerance.
  

“If your stool changes color for more than a few days without explanation and doesn’t clear up, you should see a doctor, especially if you have abdominal pain,” she says.

Are other poop changes important?

Color isn’t the only stool characteristic that matters. Pay attention if your aroma changes from your typical, and whether it sinks to the bottom of the bowl.

“It’s true that your bowel movements will never smell great,” Pulskamp says. “And it’s important to note that some foods like garlic or onions can have a noticeable impact. But the odor shouldn’t change much day-to-day. If your stool suddenly smells extra bad, comes urgently or unexpectantly, you may need to see a doctor.” Foul-smelling bowel movements can be linked to:

• Celiac disease (an immune reaction to gluten that causes inflammation in your small intestines)

• Crohn’s disease (chronic inflammatory bowel disease)

• Chronic pancreatitis (inflammation of your pancreas)

• Cystic fibrosis (a genetic condition that affects your intestines, kidneys, liver, lungs and pancreas)

• Intestinal infections

• Malabsorption

In general, stool will sink if a person is on a healthy diet. Bowel movements that float like chocolate puff cereal could mean several things. You may be eating foods that produce too much gas, you could have an infection, food intolerance, or other medical conditions such as pancreatitis.

Do poop changes mean you have cancer?

Dr. Rafferty says colorectal cancer grows slowly and typically produces few symptoms. So, it’s rarely the cause of changes in your bowel movements, especially if they appear suddenly and disappear within a few days.

“The most common symptom of colorectal cancer is that nothing’s wrong,” she says. “Most patients don’t notice a significant change until it’s pretty advanced.”

Still, she adds, talk to your doctor if you experience:

• Abdominal pain (bloating, cramps, fullness and gas

• Constipation that is new and doesn’t go away with extra fiber and fluids
  

• Diarrhea, especially if it is bloody or urgent
  

• Feeling of fullness even after you have a bowel movement
  

• Hard, pebble-like stool
  

• ​Pencil-thin stool
  

It’s also important to have a colonoscopy—the screening test for colorectal cancer—at age 45. You may need the test sooner if you have a family history of colorectal polyps or cancer. A colonoscopy can also diagnose other conditions like Crohn’s disease or ulcerative colitis that can affect your bowel movements.

Ultimately, Dr. Rafferty says, don’t ignore the signals your stool gives you about your health.

“Pay attention to what your body is telling you,” she says. “We all have different bowel habits. But if something is a change for you, don’t hesitate to talk with your doctor.”