Carnivore diet cause constipation – (cause and solution)

In this article, we will explain why carnivore diet constipation can occur.

We will also discuss whether this diet causes smelly poop and the health impacts of following a carnivore diet. And we will debunk inaccurate beliefs about the carnivore diet.

Carnivore diet constipation – will the carnivore diet make you constipated?

Carnivore diet constipation is common as the carnivore diet primarily consists of animal-based foods and excludes most plant-based foods where fibre comes from. 

It can occur due to low dietary fibre intake, which is crucial in maintaining regular bowel movements. 

Fibre adds bulk to the stool, promotes healthy digestion, and facilitates bowel movements (1).

Constipation occurs when there is difficulty in passing stools or a decrease in the frequency of bowel movements. 

To learn more about ‘common causes of constipation’, click here.

Carnivore diet constipation – how to resolve it?

While the carnivore diet restricts most sources of fibre, some individuals on the diet do choose to include a small amount of low-carbohydrate vegetables. 

Examples include leafy greens like spinach, lettuce, cucumbers, and other non-starchy vegetables. These foods can provide some fibre while still maintaining a primarily animal-based diet.

Another way to increase fibre is by incorporating fibre supplements like psyllium husk. 

Psyllium husk is a type of fibre derived from the seeds of the Plantago ovata plant. It softens the stools by absorbing water in the gut. 

Start with small doses, half a teaspoon, and gradually increase to two teaspoons. You should also drink more water when taking fibre supplements. Otherwise, it can lead to more severe constipation.

Notably, the amount of fibre obtained from these sources will be significantly lower compared to a diet rich in fruits, vegetables, and whole grains. 

The recommended fibre intake in healthy adults is 30g daily (2). However, this is unachievable if following a carnivore diet.

30g of fibre daily was shown to have a protective role for (3):

• Cardiovascular diseases
• Type 2 diabetes mellitus
• Colorectal cancer 

Another interesting study showed that people who consumed at least 30 different plant-based foods had more diverse microbiomes (4).

Greater diversity in the microbiome has been associated with a potential reduction in the risk of conditions such as (4):

• Obesity
• Type 2 diabetes
• Alzheimer’s disease etc.

Carnivore diet constipation – why is there no fibre in the carnivore diet?

Carnivore diet advocates believe humans do not require dietary fibre for optimal health. Also, they think nutrients found in animal-based foods can adequately support digestive health without the need for fibre.

Moreover, some proponents of the carnivore diet claim that a lack of fibre is not problematic and may even lead to improved digestion.

Those biased beliefs originate from cherry-picked research. 

For example, one research with 63 individuals with constipation showed improvement in bowel movement in those who followed a no-fibre diet for two weeks (5). 

After two weeks, they started following a fibre-reduced diet (3 groups: no-fibre, reduced fibre, and high-fibre) (5).

After six months, those who were following a no-fibre diet had an improvement in the frequency of bowel movements (5). 

However, individuals following a high-fibre diet still struggled with constipation after six months (5).

Despite this research on a small group of people, the role of fibre on constipation (and other areas of health) is well-established and proven in hundreds of studies (6).

Does the carnivore diet cause smelly poop?

Yes, a carnivore diet can cause smelly poop and smelly gases. 

Various factors, including the breakdown of food components during digestion, gut microbiota, and other individual characteristics, influence the odour of stool.

Animal-based foods, particularly red meat, can contain sulphur-containing compounds such as methionine and cysteine. These compounds can contribute to the strong odour of the stool (7).

The individual responses can vary, and not everyone may experience significant changes in the odour of their stool while following a carnivore diet.

What is the carnivore diet?

A carnivore diet, also known as a zero-carb or all-meat diet, is a dietary approach that emphasises consuming animal-based foods while excluding most or all plant-based foods. 

It is an extremely low-carbohydrate, high-fat, and moderate-protein diet.

On the carnivore diet, individuals eat meat, including beef, pork, lamb, poultry, and fish. Some also include other animal products like eggs and dairy, such as heavy cream. 

The diet typically excludes all plant-based foods, including fruits, vegetables, grains, legumes, nuts, and seeds.

Is the carnivore diet healthy?

The carnivore diet is extremely restrictive, which has many negative effects on health and well-being, which will be discussed in this section.

Nutrient deficiencies

A carnivore diet eliminates or severely restricts many plant-based foods, which can lead to potential deficiencies in essential nutrients, including:

• Vitamins (such as vitamin C, vitamin E, and folate)
• Minerals (such as potassium and magnesium)
• Dietary fibre
• Antioxidants

These nutrients play crucial roles in various bodily functions and overall health.

Gut health and microbiome diversity

A lack of dietary fibre from plant-based foods negatively impacts gut health and the diversity of the gut microbiome. 

Fibre is a prebiotic, a food to gut bacteria and is associated with better gut health outcomes. 

The limited diversity of gut bacteria has been linked to various health conditions, including metabolic disorders and inflammatory bowel diseases (8).

Potential for high (saturated) fat intake and increased risk of cardiovascular disease

The carnivore diet can be high in saturated fats. When consumed in excess, they can elevate cholesterol, contributing to an increased risk of cardiovascular diseases (9).

Higher consumption of red meat and processed meat and cancer incident

A meta-analysis from 2021 showed that high red and processed meat intake was positively associated with the risk of several types of cancer, such as (10):

• Breast cancer
• Colorectal cancer
• Lung cancer and many more

Summary

Carnivore diet constipation is common as the diet lacks fibre.

But this is not the only negative impact – a carnivore diet impacts gut health and potentially overall health by decreasing gut microbiota diversity as gut bacteria starve off due to lack of fibre, food for bacteria.

This diet can also cause nutrient deficiency and increase the risk of cardiovascular disease and some cancers.

To avoid all the potential risks of following a carnivore diet, eat a balanced diet that includes all the food groups.

Written by Barbara Lešnik, Student Dietitian, reviewed by Kirsten Jackson, Consultant Dietitian BSc Hons, RD, PG Cert