Carnivore diet

6 Causes of Carnivore Diet Diarrhea (& How to Stop It)

6 Causes of Carnivore Diet Diarrhea (& How to Stop It)

One of the most common reasons people quit the carnivore diet is because of diarrhea. Joe Rogan who recently tried the carnivore diet, experienced weeks of diarrhea.

Why do people get diarrhea on the carnivore diet? In this article, I’m going to tell you much more than you ever wanted to know about diarrhea.

It’s my GUT-siest article yet.

What is Diarrhea? I really need to tell you what it is? If you dont know, first off, are you an alien? If so, please send a picture. Second off, you’re a lucky soul.

As the song says... “When you're sliding into first

And your pants begin to burst, That's diarrhea, diarrhea….”

If you are familiar with it, welcome to the club.

Back to diarrhea. You know it when you feel it. Everyone has had that fart that goes wrong.

Especially those who are new to the carnivore diet.

Diarrhea is characterized by loose, runny stools. It usually disappears without any treatment.

The hardest part about diarrhea (well in fact, it’s actually really soft!) is that it has a myriad number of causes. Let’s dig in.

But, I do want to stress that if you’re getting diarrhea on the carnivore diet, most of the time it means that you need the carnivore diet most. Frankly, it’s your addiction to comfort in the form of dark runny stool being purged from your body. On the other side, with maybe a few pairs of dirty underwear, you’ll be a new person.

Soldier on.

6 Causes of Carnivore Diet Diarrhea

#1 Changing Gut Bacteria & Existing Gut Dysbiosis

One of the reasons the carnivore diet works so well is because it helps to restore your gut.

Gut issues are one of the most common health issues in the world. New evidence shows that leaky gut -- a disorder that allows toxins into your bloodstream -- is related to almost every western disease.

People with leaky gut will likely have the hardest transition to carnivore -- but they’re also the same people who need it the most.

Your gut is populated by trillions of bacteria -- more than all the human cells in your body. Terrifying right? (What is a human even if we have more bacteria cells than human cells in the body? Thats a question for another day...when the diarrhea stops…).

The macros you eat shape the types of bacteria in your gut, just like the how the environment you live in shapes the animal life present.

Some bacterie, like most westerners, are carb addicts. Others love fat. I’d like to think if I were a bacterium I’d be the latter.

When you change your diet from high carb to low carb, the makeup of your bacteria will shift dramatically.

According to this study:

“The availability of a huge variety and combination of nutrients promotes the selective enrichment of microorganisms, but both the quality and quantity of the macronutrients have an effect on the structure and function of the microbiome” <*>

As you cut out carbohydrates, the carbohydrate loving bacteria will rebel. It’s like solitary confinement for them. They fight back by giving you diarrhea...and in fact it’s quite effective.

It is also well established that the western diet leads to dysbiosis and inflammation <*> (dysbiosis is just dysregulated gut bacteria).

As your gut bacteria is getting used to the new source of fuel and killing off the excessive “bad” bacteria, diarrhea is often the result. But every time you continue to fight on, know that the weakness is leaving your body out the rear end.

Before we go on further, if you're just interested in getting the low down on some "solid" advice (bad pun intended), sign up below for 5 things to try to combat carnivore diet diarrhea.

#2 Adjusting to Fat Absorption

The second main reason why you’ll get diarrhea is because all of your body’s fat absorption machinery is asleep. As they say, if you don’t use it, you lose it. If you haven’t had to power your body off of fat for years because you’re eating a high carb diet, then your body won’t know what to do with it.

However, this is the beauty of our metabolic machinery -- it’s highly flexible (unlike my hamstrings), and can and will adjust to fat absorption. It just needs to be woken up.

How do you digest fats?

Bile is one of the most important parts of the digestion process. When you consume fats, your gut releases a hormone called CCK. This causes your gallbladder to contract and release bile that is stored there. Bile emulsifies the fats and allows for them to be absorbed from other enzymes.

Well your gallbladder is like a muscle. And similar to if you tried to bench press 300 lbs after never getting under a barbell in your life, it cannot handle the initial load and needs to get stronger.

And frankly, this just takes time and patience. Some people supplement with ox bile, but I prefer to let people work up the strength on their own, just like how I tell them not to use a smith machine.

The enzymes to adjust the emulsified fat are also asleep. And so are the cells and bacteria in your gut that help you absorb the fat <*>.

Your fat burning system needs a wake up call, but in the meantime you’re going to get a lot of diarrhea.

One other challenge with fatty acid metabolism is that as you increase fat intake, your riboflavin needs to increase. Another vitamin that many people are deficient in. Once again, the best source here is liver.

#3 Bile Acid Malabsorption

BIle synthesis is a costly process and for efficiency's sake your body recycles bile after making it. About 95% of bile production is supposed to be reabsorbed. However, some people don’t reabsorb bile properly. When this happens, extra bile ends up in your intestines and colon. This is scientifically referred to as a very bad time -- or diarrhea.

Two main things cause bile acid malabsorption.

In my opinion, the most common reason this happens on the carnivore diet is because of too much bile production -- which is actually the exact opposite of #2.

Why does this happen? Some people have broken machinery that never tells their bile production to shut off. Bile is toxic to cells in the colon and your body triggers diarrhea to get rid of it.

Approximately 30% of people with IBS, may have this condition (healthline). Now many of you new carnivores are doing the carnivore diet in the first place because of inflammation and IBS. So it’s very likely that if you come to this diet with underlying IBS, that you’ll experience diarrhea.

Another cause of excess bile production is underlying intestinal inflammation (which is related to IBS).

This study below shows that intestinal inflammation blocks the switch in your liver telling it to turn bile production off (the FXR receptor) <*>.

There’s copious evidence that this FXR receptor is implicated in most cases of bile acid malabsorption and directly tied to many underlying gut issues.

Dysbiosis also seems to be implicated in FXR <*>

As your gut dysbiosis and inflammation resolves, it should help to reactivate FXR and heal your gut issues. But if this is the reason for your diarrhea, once again, it means you need the carnivore diet most.

As I discuss more below, theres another very common and important cause of gut issues and inactive FXR.

(For more info, check out this great video here)

#4 Nutrient Deficiencies

The two most relevant nutrients for gut health are vitamin d and vitamin a -- both of which regulate bile acid synthesis and gut health. But over 90% of people are deficient in vitamin D and over 40% in Vitamin A.

As this study shows below, Vitamin D and Vitamin A both regulate bile acid synthesis and increase production. Another reason to eat beef liver, the best source of vitamin A, and get some sun.

Vitamin D is also implicated in IBS and other gut issues. A new study also suggests that vitamin D may benefit IBS <*>.

“Vitamin D deficiency was detected in 49 of the 60 patients (82%) in the IBS group and 31 of the 100 patients (31%) in the control group <*>”

Other studies on diarrhea, propose malnutrition as one of the most important risk factors.

Zinc and vitamin A deficiencies have both been shown to increase the prevalence of diarrhea <*>. Two nutrients most prevalent in animal foods and one’s that you are likely deficient in if you were not eating red meat before the carnivore diet.

Zinc is an essential component of more than 200 enzymes that play a critical role in metabolic pathways. Zinc also plays a role in gut function. Zinc supplementation in malnourished Bangladeshi children resulted in rapid reverse. <*>

A meta analysis of vitamin A trials showed an association between vitamin a deficiency and diarrhea morbidity.

Folate deficiency is another common factor. A nutrient that’s often hard to get but replete in beef liver.<*>

If you’re experiencing diarrhea, try adding beef liver to your diet. My favorite way to eat it is my brand new beef liver crisps that are thin, crunchy and salty.


#5 Too Much Protein Relative to Fat

This is one of the more common causes of diarrhea on the carnivore diet. It’s what plagued me early on. When I first adapted to the carnivore diet, this was exactly my issue (yes, this was 2000 years ago with my father Marcus. Even porcelain statues get diarrhea). Increasing my fat consumption eased these issues.

After not eating meat for years, people go full Ron Swanson and start guzzling down 3 lbs a day.

But like with fat metabolism, your body needs to adjust to an increase in protein consumption.

Even once you adjust to protein digestion, too much can still cause diarrhea. How?

Here’s a quick overview of the protein digestion process. Protein is made up of chains of amino acids. When you eat protein, your stomach secretes both pepsin and HCL, which together break the amino acid bonds (HCL breaks pepsinogen to pepsin).

After the stomach the amino acids enter the small intestine. The pancreas secretes other enzymes to break them down further in the small intestine and aid absorption. All of this machinery is asleep and needs to be reawakened.

Your body has a physiological limit on how many amino acids you can absorb and digest -- unfortunately for the bro science community who wants to drink whey protein shakes all day (and carnivores too who eat 3+ lbs of meat).

Amino acid metabolism produces ammonia which is toxic to the body and cant be excreted properly. Instead, your body converts it to urea, which is less toxic and easier to expel. This is called the area cycle.

(Insert obligatory overly complicated metabolic process chart below)

Your gut and liver have only so much capacity for this process and to excrete excess nitrogen. Consuming > 35% of calories by protein can push these limits and potentially cause

“hyperaminoacidemia, hyperammonemia, hyperinsulinemia nausea, diarrhea, and even death (the "rabbit starvation syndrome").” <*>

One pound of ribeye, for instance, is 32% of calories from protein. This is pushing the boundaries of your protein digestion limits if you’re not adding additional fat. And it’s why Arctic Explorer Viljamurr Stefansson suggested adding additional fat. Stefansson briefly flirted with the limits of rabbit starvation which can kill you <*>

#6 Inflammatory Foods on Carnivore

A number of foods that are still carnivore approved can cause gut irritation in some people.

Common culprits are the following:

  • Non ruminant foods like chicken and pork. These tend to be higher in omega 6 fat, and is a reason why Mikhaila Peterson doesn’t consume them on her Lion Diet
  • Egg whites: One of the most common allergies in the world.
  • Dairy: Inflames the large majority of people
  • Processed fat products like tallow


Diarrhea is one of the biggest hurdles to trying the carnivore diet. If you can overcome this, you can overcome anything.

If you want my guidance on continuing the carnivore diet, sign up here to try it for 30 days with my guidance.

If you're interested in some things to try to combat carnivore diet diarrhea, sign up below.