What Your Stool Says About Your Health (& When to Talk to Your Doctor About It)April 8, 2021 - Katie McCallum
You do it several times a week, and you've been doing so your whole life. It's shape, size, frequency and even color can vary, and you've probably questioned the way it looks once or twice before.
Apologies for the bathroom talk, but we're talking about your poop.
We don't typically discuss our bowel movements with others, but your stool can say a lot about you — about your health and diet, in particular.
Dr. Eamonn Quigley, gastroenterologist at Houston Methodist, is here to answer those bathroom questions you've never been brave enough to ask but have always wanted answered.
Q: Which stool is healthy?
Dr. Quigley: As you probably already know, there's variety when it comes to your stool.
When physicians talk about stool, we reference what's called the Bristol stool scale — a chart that segments stool into seven different types. Type 1 is stool that's hard and pebble-like, while type 7 is stool that's completely liquid with no solid pieces. These types are associated with constipation and diarrhea, respectively.
In general, stool types three and four are considered "normal" — with type 3 being firm (but not hard) with small cracks in the surface, while type 4 is softer and smooth, but typically still shaped as a single piece.
However, this doesn't mean that having another type of stool on occasion is a sign that you're unhealthy.
Rather than thinking of stool in terms of what's healthiest, I recommend knowing which changes in your stool are a signal that something could potentially be awry with your health or diet.
The three features of your stool to keep an eye on are:
- Its consistency
- Its color
- If it floats instead of sinks
Q: When should you be worried about your stool consistency?
Dr. Quigley: When the consistency of your stool changes significantly, you're either experiencing diarrhea or constipation.
Diarrhea is when your stool is watery, or very loose, and lacking clear shape. In addition, it can be when you find yourself having to use the bathroom more than three times per day, even if your stool isn't completely watery each time.
Constipation is when your stool has a hard, lumpy or pebble-like consistency. Often times, the stool is so hard that it's difficult or painful to pass. Constipation is also characterized by passing stool less than three times per week.
It's always worth noting changes in your bowel habits, but the occasional diarrhea and constipation aren't always a cause for concern.
For instance, stool consistency and frequency can be temporarily affected by:
- A change in your diet – consuming more fat or less fiber than usual
- Increased stress – situational events that cause excess stress to your mind and body
- Travel – whether driving, flying or sailing, traveler's constipation or diarrhea can occur with disruptions to your usual routine
If diarrhea or constipation persists and can't be tied to one or more of the above, talk to your doctor — especially if you're also experiencing abdominal pain or notice blood in your stool, as these together can be a sign of a more serious illness or health condition.
Importantly, if you're experiencing diarrhea accompanied by a fever or blood in your stool, visit your nearest emergency room. This can be a sign of infection, which can quickly become serious. Severe diarrhea can also lead to dehydration faster than you'd probably think.
Q: When are changes in the color of your stool concerning?
Dr. Quigley: Your stool is the end result of the many things you eat and drink, as well as the chemical reactions these foods undergo as they are metabolized and travel through your body. This is why your stool can vary in color (and scent) from time to time.
The only two colors you need to worry about are:
- Pale stool, which can be a sign of a bile duct blockage or other problems with digesting and absorbing your food
- Black, tar-like looking stool, which can indicate that blood is present in your stool
Talk to your doctor if you notice either of these color changes occurring in your stool.
Otherwise, the in-between shades of brown and even the concerning-looking green stool that sometimes occurs are nothing to worry about.
Q: What does it mean if your stool floats instead of sinks?
Dr. Quigley: For the most part, healthy stool is a stool that sinks.
Stool that floats can be a sign of malabsorption — in which your body is not adequately digesting and/or absorbing nutrients from the food you're eating and drinking.
If you notice that your stool is floating more often than not, it's important to be evaluated by your doctor. In this situation, you may also notice that your stool is oily.
Q: Can your stool tell you anything about your gut health?
Dr. Quigley: Recently, gut microbiome stool testing has become a popular trend. People are either looking to their gut microbiome composition to help explain stool changes, or are simply curious about their gut health.
Right now, however, stool analysis to study the gut microbiome is not yet clinically useful — apart from using clinical analyses to detect concerning infections, such as with C. difficile, Salmonella and Shigella.
Along similar lines, people often take a probiotic to promote good gut health. But if you're using probiotics to alleviate symptoms of chronic diarrhea or constipation, certain probiotics are more effective than others.
For instance, a probiotic made primarily of Lactobacillus can help diarrheal illness, especially in children. Whereas, a probiotic containing the yeast called Saccharomyces boulardii has been shown to be effective for diarrhea related to antibiotic usage.
Lastly, data supporting the usefulness of probiotics in alleviating chronic constipation is limited, although Bifidobacteria may be helpful.