Keto Boost: Diarrhea Side Effect Or Something Else?

The ketogenic diet is a popular eating plan that has gained traction in recent years for its ability to induce weight loss. The diet is high in fat, moderate in protein, and very low in carbohydrates. While it has been shown to be effective for weight loss, it can also cause some unpleasant side effects, including keto diarrhea.

Keto diarrhea is a common issue that occurs when the body is unable to keep up with the breakdown and absorption of the high amounts of fat consumed on the keto diet. This can result in watery stools and other unpleasant symptoms. The good news is that keto diarrhea tends to resolve with time as the body adjusts to the new diet. However, if it doesn't, there are some remedies that can help alleviate the problem.

High fat content

The keto diet is a low-carb, high-fat diet. This high-fat content can lead to keto diarrhea, which is a common side effect of the diet.

Fat takes longer to break down in the body than carbohydrates or protein. When you suddenly start eating a lot of fat, your digestive system can struggle to keep up. This can lead to steatorrhea, a specific type of diarrhea caused by too much fat in the stool. The body can't keep up with the breakdown and absorption of fat, and when unabsorbed fat gets into the small intestines and colon, more water is pulled in to help its passage, resulting in watery diarrhea.

The high-fat content of the keto diet can also lead to other gastrointestinal symptoms, such as nausea and bloating. It may also be the case that the body struggles to adjust to the high-fat content of the diet, and this can cause diarrhea.

To break down fat, the liver needs to produce bile. A high-fat diet requires the liver to release extra bile, and as bile is a natural laxative, this can also lead to diarrhea.

There are some things that can be done to help alleviate the symptoms of keto diarrhea. It is recommended that people on the keto diet increase their water and electrolyte intake, as well as eat more fibre and less dairy.

Lack of fibre

The keto diet is a low-carb, high-fat diet that can lead to a lack of fibre. This is because many fibre-rich foods are also rich in carbohydrates, and the keto diet restricts daily non-fibre carbohydrate intake to 20 to 50 grams. As a result, people on the keto diet often inadvertently avoid fibre, which can lead to digestive issues.

Why Fibre is Important

Fibre is essential for digestive health. It helps keep you regular by softening and adding bulk to your stools. It also feeds the good bacteria in your gut, aiding healthy digestion and nutrient absorption. A lack of fibre can lead to constipation, which is a common issue for people on the keto diet.

Getting Enough Fibre on Keto

It is possible to get enough fibre on the keto diet, but it requires careful planning. Some high-fibre, low-carb foods that can help you meet your fibre needs on keto include:

• Avocados
• Nuts and seeds (e.g. chia seeds, flax seeds, almonds, pecans)
• Cruciferous vegetables (e.g. broccoli, cabbage, Brussels sprouts)
• Raspberries and other berries
• Coconut meat
• Green beans
• Spinach
• Artichokes
• Psyllium husk

In addition to these foods, you can also take a fibre supplement like Metamucil to ensure you're getting enough fibre on the keto diet.

Symptoms of Low Fibre Intake

If you're not getting enough fibre on the keto diet, you may experience symptoms such as constipation, bloating, gas, and stomach cramps.

Adjusting to the Keto Diet

When you first start the keto diet, it's normal to experience some digestive issues like constipation or diarrhoea as your body adjusts to the high-fat, low-carb content of the diet. However, if these issues persist or become severe, it's important to consult a healthcare professional.

While the keto diet can be challenging when it comes to getting enough fibre, it is possible to meet your fibre needs with careful planning and the inclusion of fibre-rich, low-carb foods in your diet.

Artificial sweeteners

Some common artificial sweeteners include:

• Stevia: A natural sweetener derived from the Stevia rebaudiana plant that is 200-400 times sweeter than regular sugar. It may help lower blood sugar levels and is available in liquid and powdered forms.
• Sucralose: An artificial sweetener that passes through the body undigested, providing no calories or carbs. It is popular as it lacks the bitter taste of many other artificial sweeteners. However, it may not be suitable for baking as it can produce harmful compounds when exposed to high temperatures.
• Erythritol: A sugar alcohol that is 80% as sweet as regular sugar but contains only 5% of the calories. It has been shown to lower blood sugar levels and typically doesn't cause the digestive issues associated with other sugar alcohols.
• Xylitol: Another sugar alcohol that is as sweet as regular sugar but contains fewer calories and carbs. It is often found in sugar-free products and may positively impact oral hygiene. However, consuming excessive amounts can lead to laxative effects and stomach discomfort.
• Monk fruit: A natural sweetener that is 100-250 times sweeter than regular sugar and contains no calories or carbs. It has been linked to improved insulin resistance and reduced body weight.
• Yacon syrup: Derived from the roots of the yacon plant, it is rich in fructooligosaccharides (FOS), a type of fibre that the body cannot digest, resulting in fewer calories than regular sugar. It may also help reduce blood sugar and insulin levels.

While artificial sweeteners can be a helpful way to reduce sugar and carb intake, excessive consumption of certain artificial sweeteners can cause a laxative effect, leading to diarrhea. Therefore, it is important to use these products in moderation and be mindful of potential side effects.

Gut microbiome changes

The gut microbiome refers to the microorganisms in your digestive tract. It plays a central role in several aspects of health, including digestion, immune function, mental health, and disease prevention.

The keto diet may alter your gut microbiome. A high-fat diet has been found to reduce overall colon bacteria, while increasing total anaerobic microflora and Bacteroides counts. Bacteroides are usually beneficial organisms, but their overgrowth is associated with inflammatory bowel disease, severe antibiotic-resistant infections, and colorectal cancer.

A small study of people with Glucose Transporter 1 Deficiency Syndrome (a cause of epileptic seizures) found that after three months on a ketogenic diet, there was a significant increase in a group of bacteria known to produce hydrogen sulfide—a gas that causes gut inflammation and is linked to inflammatory bowel disease.

Another study of people at high risk of metabolic syndrome found that switching from a high-fat diet to a low-fat diet increased the numbers of beneficial Bifidobacterium, which was correlated with reduced fasting glucose and total cholesterol.

The keto diet can also cause a decrease in Bifidobacteria, a common probiotic. A study showed that shifting between standard and ketogenic diets dramatically changed the proportions of common gut microbial phyla Actinobacteria, Bacteroidetes, and Firmicutes, including significant changes in 19 different bacterial genera.

The keto diet can also lead to an increase in Bacteroides and a decrease in Faecalibacterium.

The high-fat, low-carbohydrate ketogenic diet causes major disruptions to our microbiota, triggering leaky gut and systemic inflammation.

The gut microbiome is influenced by many factors, including diet, geographical location, genetics, age, and gender. The stability of the microbiome is reached between two and five years of age and is overlooked by Bacteroidetes, the largest phylum of gram-negative bacteria associated with both beneficial and detrimental effects on health.

The Firmicutes to Bacteroidetes ratio is regarded as significant for gut health and is clearly linked with increasing body mass index (BMI). The levels of these two dominant bacterial species are known to shift dramatically with aging, especially Bifidobacterium and Lactobacillus genera.

The gut microbiome is also influenced by the source and type of protein consumed. Plant-derived protein, such as mung bean protein, increases Bacteroidetes while decreasing Firmicutes. Pea protein increases strains of Bifidobacterium and Lactobacillus.

Practical Recommendations to Preserve Gut Health on a Ketogenic Diet:

• Introduce the use of whey and plant proteins (e.g., pea protein).
• Reduce the intake of animal protein.
• Implement fermented food and beverages (e.g., yogurt, water and milk kefir, kimchi, fermented vegetables).
• Introduce prebiotics and specific probiotics if needed.
• Reduce the omega 3 to omega 6 fatty acids ratio (increase omega 3 while decreasing omega 6).
• Introduce an accurate quantity and quality of unsaturated fatty acids.
• Avoid artificial sweeteners and processed foods.
• Test your microbiome if needed (analysis of 16S rRNA to identify biodiversity and richness).

Bile acid malabsorption

BAM can be diagnosed through a fecal bile acid test, which involves a 48-hour stool collection, or a serum 7αC4 test, which requires fasting. Treatment options include medication such as cholestyramine, surgery to remove the gallbladder, and diet changes to reduce fat intake.

BAM is a manageable condition, but it is important for individuals experiencing chronic diarrhea to consult a doctor and discuss the possibility of BAM to receive proper diagnosis and treatment.

Frequently asked questions