Keto Diarrhea: What To Expect When Starting The Diet

The keto diet is a high-fat, low-carb, and moderate-protein eating plan that has gained popularity for its ability to induce weight loss. However, this drastic shift in dietary habits can lead to some unpleasant side effects, with many people reporting cases of keto diarrhea.

There are several reasons why someone may experience diarrhea when starting the keto diet. Firstly, the high-fat content of the diet can be difficult for the body to digest, leading to loose stools. Secondly, the increased consumption of artificial sweeteners and sugar alcohols, which are known to have a laxative effect, can also trigger diarrhea. Additionally, dairy products, which are encouraged on the keto diet, may cause digestive issues for those who are lactose intolerant. Furthermore, the keto diet may disrupt the gut microbiome, leading to inflammation and changes in gut bacteria that can affect digestion and nutrient absorption.

While keto diarrhea usually subsides within a few weeks, it is important to stay hydrated and consult a healthcare professional if symptoms persist or become severe.

High-fat content

The keto diet is high in fat, with 65-90% of calories coming from fat sources. This high-fat content can cause issues for some people, leading to keto diarrhea.

The body needs to produce more bile to digest the extra fat in the keto diet. Bile is a natural laxative, so this can speed up the passage of food through the digestive tract, leading to more frequent bowel movements. The body may not be able to reabsorb all the water from the waste, resulting in watery stools.

Some people's bodies do not absorb fat efficiently, which can also cause greasy, loose stools. This is more common in people who have had their gallbladder removed or who do not produce enough bile for fat absorption.

The high-fat content of the keto diet can also lead to bloating and nausea, as well as gas pains and flatulence. This is due to the extra bile production and increased intestinal peristalsis, or muscle contractions, needed to move the food through the intestines.

To reduce the risk of diarrhea on the keto diet, it is recommended to cut back on dairy, try probiotics and prebiotics, eat fermented foods, and reduce artificial sweeteners. It is also important to ease into the keto diet gradually, rather than making a sudden shift, to give your body time to adjust to the increased fat intake.

Artificial sweeteners

The increased consumption of artificial sweeteners on the keto diet is due to the diet's restriction of carbohydrates and sugars. People may use these sweeteners in beverages like tea and coffee or in keto-friendly products like cereals, protein bars, and yogurts. However, excessive intake of these sweeteners can lead to significant digestive distress, including diarrhoea, bloating, gas, nausea, and flatulence.

To alleviate diarrhoea caused by artificial sweeteners, it is recommended to reduce the intake of keto-friendly products containing sugar alcohols and artificial sweeteners. Additionally, increasing the consumption of high-fibre foods, staying hydrated, and adding probiotics and prebiotics can help improve digestion and reduce gastrointestinal symptoms.

It is important to note that not everyone experiences diarrhoea on the keto diet, and the impact on the digestive tract may vary. While some people's digestive systems adjust to the diet within a couple of weeks, others may experience long-term gastrointestinal issues. Therefore, it is advisable to consult a healthcare professional before making significant dietary changes and to monitor your body's response to the diet.

Gut microbiome disruption

The keto diet may disrupt the gut microbiome, which can lead to diarrhea. The gut microbiome refers to the microorganisms in the gastrointestinal tract, mainly bacteria that are essential for health and play a role in digestion, immunity, and reducing the risk of diseases.

Research suggests that high-fat diets like keto can cause adverse changes in the gut, including inflammation and a decrease in beneficial fatty acids. These changes may lead to difficulty in digesting and absorbing nutrients, resulting in diarrhea.

Some studies have found that after three months on the ketogenic diet, the bacteria in the gut change significantly, which could be a potential cause of diarrhea for some individuals. However, more research is needed to confirm this conclusion.

The disruption in the gut microbiome caused by the keto diet can be managed by taking a probiotic supplement or consuming probiotic-rich fermented foods like sauerkraut, kimchi, kefir, tempeh, and buttermilk. These steps may help support a healthy gut flora composition and improve digestion.

Additionally, easing into the keto diet gradually, rather than making an abrupt shift, can help the body adjust to the increased fat intake and potentially reduce the risk of gastrointestinal issues.

Bile production

The liver's increased bile production is one of the main causes of keto diarrhoea. Bile is a digestive fluid that helps emulsify fats, making them easier to absorb. As the keto diet is high in fat, the liver has to produce extra bile to break down all the ingested fat. This partially digested content, now mixed with bile, moves through the intestines and into the colon and bowels more rapidly. This reduced transit time means that less water is reabsorbed from the waste, resulting in runnier stools.

Bile is also a natural laxative, so this increased production can speed up the passage of waste through the digestive tract, leading to diarrhoea. This is especially true for people who have had their gallbladder removed or who do not produce enough bile for fat absorption.

The high-fat content of the keto diet can also cause bloating and nausea due to excessive bile production and increased intestinal peristalsis (the waves of muscle contractions that move food through the digestive tract).

To help alleviate these issues, it is recommended to cut back on dairy products, as they are high in fat and naturally contain some bile. Switching to plant-based, vegan alternatives can be a solution. Additionally, taking probiotic and prebiotic supplements can help support a healthy gut microbiome, which is essential for digestion and immunity.

It is also important to note that easing into the keto diet, rather than making an abrupt change, can help the body gradually adjust to the increased fat intake and bile production. This may reduce the severity and risk of diarrhoea and other gastrointestinal issues.

Dairy products

If you suspect dairy is the cause of your diarrhea, try eliminating it from your diet or switching to plant-based, vegan alternatives like cashew cheese, hemp milk, almond milk, coconut yogurt, and coconut milk. This may help alleviate your symptoms.

Additionally, be mindful that dairy is known to cause GI upset, so if you're experiencing tummy troubles on keto, it's worth trying to remove cream and cheese from your diet to see if that helps.

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