Does the Carnivore Diet Cause Constipation?

A carnivore diet, or carnivorous diet, is a type of eating plan that only allows for animal products. The carnivore diet has been gaining popularity because it’s seen as a way to completely eliminate carbohydrates, as a means to improve gut health.

But how nutritious is the carnivore diet really? Can this, or any other extreme elimination diet, improve your digestive health?

Read on to find out if this restrictive eating style will cause more harm than good!

In this post, we’ll be looking at the most common extreme elimination diets – including the carnivore diet – that are used for digestive health goals…and clue you in on if we recommend them.

What are elimination diets?

There are many examples of restrictive elimination diets, including the carnivore diet, paleo, keto, and AIP.

The goals vary by person, but our clients have one thing in common.  They want to get relief from digestive health symptoms such as diarrhea, bloating, and constipation that goes hand in hand with IBS and SIBO.

It’s important to note that elimination diets are intended to be used as a temporary therapy.

This is a common mistake that we see with clients who have been on an elimination diet for far too long. Our goal for our clients – and the science supports – is as varied of a diet as possible. Elimination diets can be therapeutic, but like a splint on a broken bone, they’re not meant to be used for the long run.

If they’re not approached mindfully and with respect for your body, you could find yourself feeling worse than when you started the diet! So, let’s take a closer look at some of these popular options…and see if we recommend them or not.

Let’s start with the most restrictive: the carnivore diet.

What is the carnivore diet?

The carnivore diet is an incredibly restrictive diet plan that allows for only animal foods, including meat, fish, poultry, and eggs. As such, the diet is essentially fiber-free.

The carnivore diet is also known as the zero carb or all-meat diet.

Allowed foods include:

• Meat, including beef, pork, lamb
• Organ meat, such as liver
• Poultry
• Fish
• Water

And depending on whose guidelines you follow, you may also be permitted to eat and drink:

• High-fat dairy (butter, cream)
• Eggs
• Coconut oil (this is controversial)
• Coffee and tea
• Salt, pepper, and spices

Foods not permitted on the carnivore diet include:

• Fruits and vegetables
• Grains
• Low-fat dairy products (milk, yogurt)
• …basically anything else

Why do people follow the carnivore diet, and is it healthy?

There are a number of reasons why someone might try this restrictive plan, including improved digestive health, diabetes management, and neurological conditions where they have lost their appetite for most foods.

This carnivore diet plan is most notably promoted by Shawn Baker, an MD and Orthopedic Surgeon. Baker published a book in 2019 called the Carnivore Diet.

We should note that his New Mexico medical license was revoked in 2017 and reinstated with stipulations in 2019 (1).

Who eats a carnivore diet?

There are few people who eat a meat-centric diet. One example is the Alaskan native population: their traditional diet is meat-centric, including seal, whale, fish, poultry, eggs, and polar bear meat (2). But even so, they still included berries, tubers, seaweed, and other plant foods.

From a nutrition perspective, are there any pros to a meat-centric way of eating?

As the carnivore diet is so restrictive, there are very few benefits to this diet. Anecdotally, some people do report they feel better on the carnivore plan with weight loss but that could be due to their reduced intake of carbohydrates and food in general. Animal protein is very filling.

We can get behind a recommendation for more protein, especially at breakfast. We often see clients who have a carb-heavy breakfast and end up hungry and fatigued a short time later because of it. For more details about our protein recommendation, check out this post: How Much Protein Do You Need & When Should You Eat It?

But overall, this diet plan is not backed by science. In fact, the only known study about the carnivore diet was published in 2021. In the study, 2,000 people who are self-reported to be following the carnivore diet were surveyed (3). It did not include those who tried a carnivore diet without success.

But, the vast majority of the available research about general health and nutrition – including the benefits of fruits, vegetables and whole grains  – goes strongly against the radical claims of the carnivorous diet. 

Are there any cons of a carnivore diet?

There are many. The carnivore diet can lead to nutrient deficiencies, including fiber. Not getting enough fiber is a recipe for constipation and poor gut health.

The friendly bacteria that live in your gut and promote your own health and wellness need fiber to thrive; the fiber that your body cannot digest is their food. In fact, the greater variety of plant foods eaten will cultivate a diverse microbial community in your own gut: this is a big health boost (4).

Can the carnivore diet cause constipation?  Based on this questionnaire of 2,000 followers of a carnivore diet noted above, 45% of those reported not having daily bowel movements. 

Can the carnivore diet cause nutrient deficiencies? I used Cronometer to assess a day on a 2,000 calorie Carnivore diet, which included:

• Skinless, boneless chicken breast
• Eggs
• Sirloin steak
• Bacon
• Cheddar cheese
• Salmon
• Olive oil

This diet provided most B vitamins, with the exception of folate.  It also provided minerals including potassium, zinc and selenium.  What was missing?

In addition to folate, this diet was low in vitamin A, vitamin C, vitamin D, vitamin E, vitamin K, calcium, copper, iron, magnesium and manganese.  These are essential nutrients that can support gut health, immune health, bone health, energy metabolism and more.

So, you can see how any restrictive diet can easily cause nutrient deficiencies.  A varied diet ensures you get most of the nutrients you need to feel your best.

Let’s compare the carnivore diet to two other popular elimination diets, starting with the AIP diet. 

What is the AIP Diet?

AIP stands for Autoimmune Protocol. There are actually several different versions of the protocol, but no matter what, it is a restrictive plan.

For most practitioners, AIP eliminates the foods that may be contributing to increased inflammation and symptoms of an autoimmune condition such as Hashimoto’s thyroiditis, multiple sclerosis (MS), and Inflammatory Bowel Disease (IBD).

The AIP plan can be low in carbohydrates and includes animal protein, healthy fats, most vegetables and fruit (but not all nightshades). The AIP Diet eliminates grains and dairy. Nuts and seeds are typically eliminated at first, and may be reintroduced. Some advocates recommend eating them after they’ve soaked or sprouted to remove phytates.

Some versions of AIP also eliminate eggs, coffee, and chocolate for a short time to reduce inflammation and improve poor gut health.

Again, it’s very important to follow the elimination period with structured food introductions so you know just what is triggering symptoms and what can be successfully added back into the diet.

What are the pros of the AIP Diet?

There are more research studies to base claims on here. The AIP has been found by scientific studies (as opposed to website testimonials) to be helpful in a number of conditions:

• Fewer symptoms for those with IBD (5).
• Improved quality of life and fewer symptoms for those with Hashimoto’s disease (6).
• Fewer symptoms for those with rheumatoid arthritis after the elimination of lectins (7).

And the cons?

Any version of the AIP diet is very restrictive. This impacts a person’s mental health, the ability to socialize with friends and family, and can make the grocery bill pretty hefty.

We are fans of creative solutions, but we have to weigh the pros and cons carefully. And remember, elimination diets are not intended to be used long term. There are benefits of an elimination period, but reintroductions to liberalize the diet are just as important.

And just to compare one more low-carb elimination diet.

The Keto Diet

This is a diet that is extremely low in carbohydrates and high in fat – has been used for a variety of purposes and has the most evidence to help people with epilepsy. The Keto diet is also used for weight loss. Unfortunately, this diet can impair gut health.

Because the keto diet largely eliminates fruit, starchy veggies and whole grains, you’re missing the fiber that only occurs in these foods. Not only does fiber help to keep your digestion and elimination regular, fiber is also food for the beneficial bacteria that live in your digestive tract (8).

With less fiber, people tend to have a less healthy ecosystem. Those bugs are hungry!

In addition, a high fat diet may further alter the ecosystem: one study found that a high-fat diet impaired the health of those healthy bacteria as well as increased inflammatory markers (9). This is not a good change!

Not all research finds harm with the keto diet. One small study found relief for those with IBS-D after following a four week, very low-carb diet (10). To us, this further emphasizes that elimination diets can be helpful, but do not need to be followed long term.

Key Takeaways: Carnivore diet, constipation, and other elimination diets.

As clinical nutritionists, we are not swayed by social media “success” stories and less than rigorous medical studies. We protect our clients from false claims and help them to achieve remission from their digestive health symptoms through the careful application of rigorous science.

If you find it hard to digest food groups like carbohydrates, the answer isn’t to eliminate them entirely. The key to long term relief is understanding why they are hard to digest and addressing the root cause. We have worked with hundreds of clients with IBS, SIBO, GERD, Celiac disease, food sensitivities, and it is rare that anyone had to eliminate all carbohydrates to get symptomatic relief.

Our client Pamela came to us having been on a very low carbohydrate diet. She was suffering from long-term chronic constipation, bloating and fatigue. After just a few weeks of including easier to digest carbohydrates, all of these symptoms improved. Here is what Pamela had to say:

“I have to tell you that I’m in shock as to how I was able to eat 2 slices of pizza!… I am in shock because my stomach didn’t blow up and I don’t have any discomfort.”

Pamela

Ultimately, we want our clients to be on the broadest diet possible with the fewest symptoms. And while carefully implemented elimination diets can be helpful, we want to make sure that the interventions are doing more good than harm. And it’s important that they are short-term and should always include food reintroductions.

If you’ve been struggling with unrelenting digestive symptoms, we’d love to help you feel better. Use this calendar to book a Free 15-Minute Strategy Session to learn more about our approach to your case. We promise that we’ll be recommending more than just steak at every meal.