Keto Diarrhea: When Will It End?

The ketogenic diet is a popular, low-carb, high-fat eating plan that has been hailed as an effective way to lose weight. However, it can also lead to an unfortunate side effect: keto diarrhea. This is characterised by loose, watery stools and is often the result of increased fat intake, decreased fibre intake, and changes in gut bacteria. While keto diarrhea tends to resolve with time, there are several ways to alleviate it, including cutting back on dairy, consuming probiotics and prebiotics, and easing into the diet gradually.

High-fat content

The keto diet is a low-carbohydrate, high-fat diet. The basic idea behind the keto diet is to restrict carb intake so that the body switches from burning glucose (sugar) for energy to burning fat, including stored body fat and dietary fat. This shift in metabolism is known as ketosis.

The high-fat content of the keto diet can be a common cause of diarrhea. 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 may struggle to keep up. Some of the fat may not be broken down properly and may be excreted in your stool. This can lead to steatorrhea, a type of diarrhea with high amounts of fat in the stool, which is typically pale, foul-smelling, and coated in a thick, greasy film.

The high-fat content of the keto diet can also lead to other gastrointestinal symptoms such as nausea and bloating. The liver needs to produce more bile to break down the increased amount of fat in the diet. As bile is a natural laxative, an excessive amount may push waste through the digestive tract faster than usual, leading to diarrhea.

Additionally, the keto diet may also include higher amounts of artificial sweeteners and sugar alcohols, which can be hard to digest and cause bloating and diarrhea when consumed in excess.

To alleviate diarrhea caused by the high-fat content of the keto diet, it is recommended to:

• Add more fiber to your diet, such as citrus, berries, avocado, broccoli, and chia seeds.
• Drink more water and electrolytes to stay hydrated and replace lost fluids.
• Gradually ease into the keto diet by slowly reducing carbs and increasing fats, allowing your body to adapt better.
• Consult with a registered dietitian to ensure you are meeting your nutritional needs and getting enough fiber.

Artificial sweeteners

Sugar alcohols, such as sorbitol, maltitol, and xylitol, are common culprits of keto diarrhea. These sweeteners are not effectively absorbed in the gut and can have a laxative effect. Erythritol, a sugar alcohol found in fruits like grapes and watermelon, may be better tolerated and is considered safe by the FDA. Stevia, a natural sweetener derived from the Stevia rebaudiana plant, is also recognised as safe and can be used as a substitute for sugar in coffee and tea. Monk fruit, a sweetener native to China, is another option that is recognised as safe and does not affect blood sugar levels.

It is important to note that not all artificial sweeteners will cause diarrhea, and individual tolerance may vary. However, if you are experiencing digestive issues while on the keto diet, it may be worth re-evaluating your sweetener choices and consulting with a healthcare professional.

Dairy products

If you suspect dairy products are causing your keto-related diarrhoea, consider switching to plant-based, vegan alternatives such as cashew cheese, hemp milk, almond milk, coconut yoghurt, or coconut milk. Eliminating dairy may help alleviate your symptoms.

In addition, the keto diet can disrupt the gut microbiome, so taking a probiotic or prebiotic supplement can help support the health and optimal composition of your gut flora. Studies have found that taking a probiotic supplement while on the keto diet may help offset the digestive issues and gut microbiome disruption caused by the diet. Eating fermented foods such as sauerkraut, kimchi, kefir, tempeh, and buttermilk can also be beneficial, as they contain natural probiotics that are nourishing to the gut microbiome and help populate your digestive tract with the healthy bacteria needed for optimal digestion.

Gut microbiome disruption

The keto diet is a low-carbohydrate, high-fat diet that has gained popularity in recent years for its potential benefits in lowering inflammation, promoting weight loss, and improving heart health. However, the keto diet can also lead to "keto diarrhea", which is characterised by loose, watery stools. One of the possible causes of keto diarrhea is gut microbiome disruption.

The gut microbiome refers to the collective genome of the microorganisms (mostly bacteria, but also viruses, fungi, and protozoa) that inhabit the large intestine or colon. These microorganisms thrive on a diverse array of carbohydrates, including fibre, resistant starch, and non-starch polysaccharides, which are found only in plants.

The keto diet's restriction of carbohydrate consumption can lead to a decrease in the abundance of certain beneficial bacteria and an overrepresentation of others, which can have negative health consequences. For example, an increase in the bacteria Bacteroides, which are normally beneficial, has been linked to inflammatory bowel disease, severe antibiotic-resistant infections, and colorectal cancer. Additionally, a high-fat diet increases intestinal permeability, causing a "leaky gut", and can also lead to an increase in bacterial species associated with inflammation.

Several studies have found that the keto diet alters the composition of the gut microbiome. A small study of people with Glucose Transporter 1 Deficiency Syndrome found that after three months on a ketogenic diet, there was a significant increase in 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 and reduced fasting glucose and total cholesterol.

The exact mechanisms by which the keto diet alters the gut microbiome are still being studied. However, it is clear that the keto diet can have a significant impact on the composition and function of the gut microbiome, which can have both positive and negative effects on health.

Excess bile production

The keto diet is a high-fat, low-carbohydrate, and moderate-protein diet. It is a significant shift from the standard American diet, and as such, it can cause some digestive issues, including diarrhea.

One of the reasons for this is the increased bile production required to digest the high amounts of fat in the keto diet. Bile is released by the gallbladder to help emulsify and prepare fats for absorption. The shift from low to high bile production can be challenging for the body to adjust to, and this may lead to bile acid malabsorption.

Bile acid malabsorption occurs when the body struggles to reabsorb old bile, which can then linger in the small intestine, leading to diarrhea. This is more common in individuals with pre-existing digestive issues such as IBS, IBD, Crohn's disease, celiac disease, or SIBO.

To support the body in this transition and reduce the risk of diarrhea, one can consider supplementing with ox bile, which can assist with fat digestion until the gallbladder adjusts to the new diet. Additionally, certain digestive enzymes like amylase and lipase can also help with fat assimilation.

It is important to note that while bile production is crucial for fat digestion, excessive bile can also act as a natural laxative, pushing waste through the digestive tract faster than usual, which can also contribute to diarrhea.

Tips to Manage Excess Bile Production and Diarrhea:

• Consider supplementing with ox bile or digestive enzymes like amylase and lipase.
• Stay hydrated and ensure adequate electrolyte intake, especially during the initial transition phase.
• Try the carnivore-adjacent diet or the cyclical ketogenic diet, which includes small amounts of fruits and root vegetables, to reduce deeply ketogenic states and lower dietary fat requirements.
• Ensure adequate intake of fat-soluble vitamins like Vitamin A and Vitamin D, which directly regulate bile acid production. Address any nutrient deficiencies, as they can increase the risk of keto diarrhea.
• Monitor protein intake, as excessive protein can also lead to diarrhea. Aim for about 10-20% of your daily energy needs from protein.
• Choose healthy sources of dietary fat, such as olive oil, high-oleic safflower and sunflower oils, coconut oil, lard, butter, cream, and high-fat cheese. Avoid excessive vegetable and seed oils high in omega-6 fats, which can cause digestive distress.
• Stay active with gentle exercises like yoga or short, brisk walks after meals, which can help regulate bowel health and frequency.

By following these tips and giving your body time to adjust, you can help manage excess bile production and reduce the risk of diarrhea while on the keto diet.

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