Keto And Loose Stool: What's The Connection?

The keto diet is a high-fat, low-carbohydrate eating plan that has gained popularity in recent years as a quick and effective way to lose weight. However, one unfortunate side effect of this diet is keto diarrhoea, which is characterised by loose, watery stools. This is caused by several factors, including an increase in fat intake, a decrease in fibre intake, and changes in gut bacteria. The high-fat content of the keto diet can lead to steatorrhea, a specific type of diarrhoea caused by too much fat in the stool. Additionally, the sudden lack of fibre that comes with cutting out carbohydrates can also lead to diarrhoea. Artificial sweeteners, often used in keto desserts, can also be hard to digest and cause an upset stomach. Changes to the gut microbiome due to a lack of plant foods can also lead to an increase in the frequency of diarrhoea and other nasty side effects.

High-fat content

The keto diet is a low-carb, high-fat eating plan, with fat comprising 65-90% of a person's daily energy intake. This high-fat content can cause loose stool or "keto diarrhea" as a side effect.

Fat takes longer to break down and be absorbed by the body than carbohydrates or protein. When switching to a high-fat diet like keto, the body may struggle to keep up with the breakdown and absorption of fat. As a result, some of the fat may be malabsorbed, meaning it is not broken down properly and is excreted in the stool. This can lead to steatorrhea, a type of diarrhoea characterised by loose, watery stools with high amounts of fat.

Additionally, the liver needs to produce bile to break down fat. A high-fat diet causes the liver to release extra bile, which acts as a natural laxative. An excessive amount of bile can push waste through the digestive tract faster than usual, leading to diarrhoea.

The high-fat content of the keto diet can also lead to other gastrointestinal symptoms such as nausea, bloating, and abdominal discomfort. It is important to note that these issues are usually temporary as the body adjusts to the new diet. However, for some people, keto diarrhoea may be a long-term side effect.

To alleviate these issues, it is recommended to increase your intake of fibre, water, and electrolytes. Staying hydrated is crucial, especially if you are experiencing diarrhoea, to replace lost fluids and electrolytes. Adding more fibre to your diet can help absorb water and calm diarrhoea. However, it is important to be mindful of the type of fibre you consume. Insoluble fibre, found in non-starchy vegetables, nuts, avocado, and seeds, is recommended as it bulks up stools and helps prevent diarrhoea.

If you are experiencing persistent or severe diarrhoea, it is important to consult a healthcare professional. They can help determine if there are any underlying issues and provide guidance on managing your symptoms.

Lack of fibre

The keto diet is a high-fat, low-carbohydrate eating plan that has gained popularity in recent years as a quick and effective way to lose weight. However, one unfortunate side effect of this diet is "keto diarrhoea", which is characterised by loose, watery stools. One of the main causes of this condition is a decrease in fibre intake, which can lead to digestive issues and changes in the gut microbiome.

Why Fibre is Important

Fibre is crucial for gut motility and function, and it helps to add bulk to the stool, making it easier for the colon to move things through. It also promotes the growth of good bacteria in the gut, which can have anti-inflammatory effects and improve blood glucose regulation. Additionally, a certain type of fibre called insoluble fibre may help control blood sugar and improve insulin sensitivity.

The Impact of Keto on Fibre Intake

The keto diet restricts carbohydrates, which means that people following this diet are likely to consume less fibre. This is because fibre-rich sources such as fruits, vegetables, whole grains, and legumes are limited or cut out completely. As a result, the gut microbiome can be affected, leading to digestive issues such as diarrhoea and constipation.

Managing Fibre Intake on Keto

To prevent and manage these gastrointestinal symptoms, it is important to include high-fibre, keto-friendly foods in your diet. Some examples include non-starchy vegetables like broccoli and artichokes, fat sources like avocado and nuts, and fermented foods like sauerkraut and kimchi. Additionally, staying hydrated and taking a fibre supplement can also help. However, it is important to note that it may be difficult to get all the fibre you need from supplements alone, so a well-planned diet that includes high-fibre foods is crucial.

Artificial sweeteners

Sugar-free and low-carb products often contain sugar alcohols such as xylitol, sorbitol, mannitol, maltitol, lactitol, and isomalt. These sugar alcohols have been known to cause gastrointestinal distress, including gas, nausea, and diarrhoea. This is because sugar alcohols are not effectively absorbed in the gut and often reach the large intestine undigested, where they have an unpleasant laxative effect.

To avoid these unpleasant side effects, it is recommended to cut back on the intake of foods and beverages that contain artificial sweeteners and sugar alcohols.

Gut microbiome changes

The keto diet can impact the composition of your gut microbiome, which has implications for digestion. Some studies have found that after three months on the ketogenic diet, the bacteria in the gut change quite a bit, and this could cause diarrhoea in some people. If your body is not used to eating more fats, this could alter the gut bacteria, causing diarrhoea and looser stools from poor digestion.

The gut microbiome may also play a role in disease prevention and progression. Research in animals and some human data shows that high-fat diets lead to fairly rapid and significant changes in the microbiome. However, the long-term health implications of these changes are not yet known.

The keto diet restricts carbs, so you are likely eating less fibre, which comes from carbs like fruits, legumes, starchy foods, and grains. A decrease in fibre intake can lead to diarrhoea and other gut-related problems like changes to the gut microbiome.

Certain carbs are especially beneficial for the gut microbiome, particularly those high in fibre and nutrients like fruits, vegetables, and whole grains. These foods promote the growth of good bacteria in the gut. A decrease in carbs has been shown to affect the gut microbiome by decreasing the abundance of good bacteria, which can lead to gut-related problems like diarrhoea and inflammation in the gut.

Without fruits, vegetables, and other plant foods, you won't be getting much prebiotic fibre. And without prebiotic fibre, the healthy probiotic bacteria in your gut won't have the food they need to thrive. So, keto has the potential to worsen your digestive health overall by reducing the healthy bacteria in your microbiome. That can lead to an increased frequency of diarrhoea and other nasty side effects.

If you've been on the keto diet for several weeks or months and you're just starting to experience diarrhoea, it could be due to these unfavourable changes in your gut microbiome.

Sugar alcohols

While sugar alcohols can be a great way to enjoy sweets without disrupting ketosis, they do come with a downside. For some people, consuming large amounts of sugar alcohols can lead to digestive issues like bloating, gas, and even diarrhea. This is because sugar alcohols are not effectively absorbed in the gut and often reach the large intestine undigested, causing an unpleasant laxative effect.

To avoid potential digestive issues, it is recommended to start slowly with sugar alcohols and let your body adjust to these new sweeteners. Always check product labels to see what type of sugar alcohol is used, and pay attention to how your body reacts to adjust your intake accordingly.

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