Got Gut Health? Part 1: Defining Good Digestion

by | Dec 22, 2022 | Featured | 0 comments


The topic of gut health is becoming more and more prominent in the health and fitness space; but there are a lot of complexities and nuances involved in assessing issues and finding the right recipe for success for each individual.

Like many subjects in the health and fitness industry, the topic of gut health is particularly prone to conflicting information, and it can be really confusing as to where to start in troubleshooting gut issues, or if they even need to be troubleshooted!

There are many ways to get the gut to a healthier place; from the basics of increasing food quality and ditching your standard american diet type foods to more advanced interventions such as an elimination diet with specific supplementation interventions.

But to what extent does digestion need to be aberrant enough to warrant a protocol? Is there any amount of gas that is “normal”? What about bloating and stomach distension? And that loose stool you get each time you eat pizza is totally normal, right? In this post, we’ll be discussing an evidence based view on what good and bad digestion actually is – And when someone might benefit from a gut protocol. 


  • Breaking down “normal” digestion 
  • What is normal, healthy stool and bowel movement frequency?
  • Is there a normal level of gas or is all gas indicative of gut issues?
  • How do we distinguish between minor transient gut changes vs. a deeper, chronic issue? 


Readers be warned – this section features your fair share of toilet talk, but if you’re an astute coach, you’re having these conversations with your clients regularly. There’s many aspects to stool worthy of consideration, but the two easiest factors to address that provide valuable insights are form and frequency:


Many of you might be familiar with the Bristol stool chart, but many may not be. It was developed in England by Stephen Lewis and Ken Heaton at the University Department of Medicine, Bristol Royal Infirmary. It was suggested by the authors as a clinical assessment tool in 1997 after a previous prospective study conducted in 1992 had shown an unexpected prevalence of defecation disorders related to the shape and type of stool. So it’s well-validated, and has stuck around till today and is still commonly used to assess digestive disorders and gut health. 

A bristol stool chart is divided up into 7 variations of stool, from diarrhea to normal to chronic constipation (picture below). Types 3 and 4 would be normal. Anything below type 3 is not ideal and can be indicative of constipation, and anything above type 5 is tending towards diarrhea. Part of the brilliance behind the Bristol stool chart is that it is relatively easy to use and implement as an assessment tool. 

However, there are many things that can be going on causing constipation/diarrhea. In a nutshell, slow intestinal transit (which gives time for more water to be reabsorbed), dehydration, IBS, SIBO, and IBD could potentially be causing constipation, whereas fast intestinal transit (not enough time for water to be reabsorbed) can cause diarrhea, but some of the other issues I just described – IBS, SIBO, and IBD – could also be causing diarrhea. This is most likely due to dysbiosis at the root of IBS/SIBO, and there’s good evidence that autoimmune IBD begins with a dysbiotic microbiome which can contribute to other issues. Examples of other health complications with a strong gut dysbiosis component include autoimmune diagnoses such as hashimotos. 


The second consideration when it comes to healthy digestion is bowel movement frequency. A normal stool frequency is going to depend on a few factors, but in general, most people should be going at least once a day. Once every other day can be “normal” in some situations, but if you’re only going once or twice a week, then this falls into the category of chronic constipation. Situations where you might have decreased stool frequency, maybe once every other day, and it still be “normal” would be things like:

  • If you’re deep into a calorie deficit (reducing food portions and energy availability) and low on food in general. If you have less food coming in, you’re going to have less waste going out. Being very deep into a cut and getting very lean, we may have downregulation of the thyroid axis, which could be contributing to slower transit times and lead to the possibility of some transient constipation. This is not necessarily “normal”, but normal for the context of where you’re at at the time and easily reversible.  This is not necessarily “normal” or something that we would want to occur for long periods of time, but it is easily reversible, and normal within the context of a significant energy deficit. 
  • Another possible consideration is if you’re eating a very low-waste diet. A diet like a carnivore diet or keto diet that doesn’t have a significant amount of indigestible fiber is most likely going to cause less frequent bowel movements, but I’d still say max every other day in this situation to be “normal”.  In this situation we’d still strive for daily bowel movements, or a minimum of every other day on the slower side of transit time.

Example 1: When examining stool frequency it is important to consider this variable within the context of other symptoms and biofeedback. For example, straining when attempting to pass a bowel movement, excessive fullness, or abdominal pain would be indicative of larger problems. Pairing any of these with decreased stool frequency provides insights into potential issues that are not normal, or optimal in terms of digestive health. Any of these symptoms would be indicative of underlying gut troubles beyond low waste or food intake.

Example 2: “Also be mindful of other symptoms that may be present. Examples include: fullness weighing you down, abdominal pain, or straining when going to the bathroom”

Conversely, if you’re going several times a day, this can also be healthy and normal. Stool form would be the first thing to look at here. If it’s anything above a 4 on the bristol chart, then it’s not a good thing, but if you’re going 3-4x a day and your stool comes in at a 3 or 4, then I’d look at the rest of your lifestyle. 

Do you eat a very high fiber diet? Are you in a mass-gaining phase right now and are just eating excessive amounts of food in general? If those are the case, and stool form is good, then going several times a day could also be normal. 

When is diarrhea/constipation a big issue vs. transient?

There are occasions when diarrhea/constipation is a huge issue vs. a transient thing that “works itself out”, so let’s ask ourselves a few questions.  

If your diet is full of processed foods, high in sugar, devoid of vegetables, etc, and you have constipation or diarrhea every now and then, then the first step is to minimize the amount of processed foods, include more whole, micronutrient, fiber dense foods, and see if it resolves. If it resolves after taking the basic steps, then while there still might have been an underlying issue, it wasn’t a serious or tough-to-resolve one. 

If you’re eating mostly whole, micronutrient and fiber dense foods, drinking enough water, etc, but still have issues – Ask yourself how often? Frequency of constipation/diarrhea is going to be a big determinant here. 

Acute vs. chronic

Chronic constipation is defined by the medical field as 3 or less bowel movements per week for at least 3 months, whereas chronic diarrhea is defined as having regular loose stools for at least 4 weeks. 

If your constipation is acute – This could be due to pretty benign factors. For example, when you’re doing a lot of travel – airplanes are dehydrating because the change in atmospheric pressure causes fluid shifts to the lower extremity and induce changes in blood viscosity which can accelerate dehydration; couple that with the fact that airplane cabin air is near 0 percent humidity and it’s a recipe for dehydration. This could also occur due to any interruption to a dietary routine that might cause you to be eating less fiber for the time being. 

It’s a similar situation with diarrhea; if it’s acute, then perhaps there was a bug on those vegetables you didn’t wash fully, or in the sushi or medium rare steak you ate for lunch. However, even acute bouts you should still pay attention to as they may be a harbinger of a developing issue. It could potentially be due to a food sensitivity, and the more you trigger that food sensitivity, the more frequent you’ll be inducing intestinal inflammation, which could develop into more serious issues. 

If either of them are chronic, then it’s definitely a serious issue and should be evaluated by a doctor for rote medical issues, like small or large intestinal wall problems. If serious medical issues are ruled out, and it’s just deemed “IBS” or idiopathic, then it should be addressed through elimination and a full gut protocol, if necessary (if all the basic factors are covered already).

Gas and Bloating

For many, it can be tough to delineate normal gas from problematic gas and bloating.

We can look at a few things to crudely assess this – These are frequency, scent, and presence of other symptoms like stomach distension/GERD/etc. 

There are two factors going into gas production – The diet and how many residues (i.e. fiber) are present, and the types and amounts of microbes in the gut. Further, there are two factors going into whether symptoms are present – The type and amount of gas, and the sensitivity of the subject’s gut. 

Whenever someone is experiencing severe bloating or pain along with excess gas, that’s an indication they have what’s called “visceral hypersensitivity”. Visceral hypersensitivity just means that the gut becomes very sensitive to things like gas production and excess fecal matter, and even a small amount of gas can give them symptoms like pain and bloating, whereas if the same amount of gas was produced in a healthy subject, they’d barely feel it, if at all. Visceral hypersensitivity is a hallmark of IBS, SIBO, and IBD.

If the bloating is a chronic thing, as in they’re getting bloated and gassy very frequently on a daily basis, then this is an indication that they may have a real gut issue going on. 

Let’s dig a little further into types of gas. Hydrogen and CO2 are the main gasses produced in a healthy gut, but in some versions of SIBO, methanogenic bacteria can dominate and then methane becomes the dominant type of gas produced. This will have a different scent than normal and the presence of chronic constipation can be indicative of methane-dominant SIBO. The presence of methane in the large intestine significantly slows down transit time. Hydrogen can also be overproduced in SIBO, and this is the second most common type. Diarrhea is the predominant symptom in hydrogen SIBO. 

A third, more rare type of SIBO is hydrogen sulfide dominant. Hydrogen sulfide is another gas that is produced in everyone, but in dysbiotic situations can be overproduced. This type of gas is going to give that really nasty, sulfur-type scent. So if your gas chronically smells like this, there may be an issue going on. Don’t get me wrong, nobody’s farts smell like roses, but there’s a difference between things smelling mildly bad for a small amount of time vs. room-clearing, offensive farts that stick around and have that sulfur scent. 

To recap, if you have gas, but it’s not super frequent (think like 10ish times per day, not 10ish times per hour), not accompanied frequently by bloating, pain, etc, and it also doesn’t have an extremely strong, abnormal scent, then this is probably normal gas. 

Touching on Other Symptoms

Now that we’ve covered the more nuanced pieces of the topic, the other symptoms are a little more cut and dry. There is no amount of acid reflux or GERD that is normal. If reflux is present then it should certainly be investigated further as to the source. 

In terms of bloating and stomach distension, we talked a bit about this already, so you should be halfway clued in, but chronic bloating and stomach distension is not normal either and should be investigated. 

Remember, we’re thinking about types/amount of gas and sensitivity of the subject. If someone just ate an abnormally large meal, and experiences bloating as a one-off, then it’s probably not indicative of an issue. 

Similarly, if someone downs 50-60g of fiber in one sitting, which is not too unheard of these days with low carb wraps/breads and things like Quest bars providing around 15g of fiber per serving, then the volume of gas produced is going to be large.

Even a healthy person without visceral hypersensitivity can potentially experience bloating because of the large amount of gas produced, so look at these types of things and frequency – If it’s chronic, daily bloating from normal sized meals, then it’s probably an issue. 

Wrapping it Up

Hopefully this has been helpful – I know some people out in the space that, if they pass gas once a day, they’re chomping at the bit to look for gut health remedies, which they probably don’t need to do if it’s only at that level. 

To give a final recap:

  • You always want a 3 or 4 on the bristol stool chart.
  • Passing gas several times a day is fine as long as you’re not experiencing daily bloating/stomach distension along with it and you’re not making peoples eyes tear up and clearing rooms with the smell. 
  • If you have daily GERD, daily bloating or pain, smelly, very frequent gas, and anything above or below a 3 or 4 on the Bristol stool chart consistently… You should probably make some changes, which we’ll get to in the rest of the series. 

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