Vegan Diarrhea: What's Causing It And How To Stop It

Diarrhea is a common issue for people transitioning to a vegan diet. It can be caused by a sudden increase in fiber intake, which is common in plant-based diets. Beans, whole grains, and fruits are high in fiber and can lead to digestive issues if consumed in large quantities. Additionally, some people may have food allergies or intolerances to certain vegan foods, such as soy or gluten. Other possible causes of diarrhea in vegans include zinc deficiency, small intestine bacterial overgrowth (SIBO), irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD). If diarrhea persists or is severe, it is important to consult a healthcare professional.

High-fibre foods

When switching to a vegan diet, it is common to experience an increase in fibre intake, as plant-based diets tend to be rich in this nutrient. However, this sudden increase in fibre can lead to digestive issues, including gas, bloating, and diarrhoea.

If you are experiencing diarrhoea on a vegan diet, it is recommended to reduce your fibre intake and then gradually add it back in. Here are some tips to help you manage your fibre intake:

• Keep a food journal to identify any problem foods. Track your daily meals, fibre intake, and any changes in your stools. This will help you pinpoint specific foods that may be causing issues.
• Focus on lower-fibre vegan foods, such as cooked potatoes or sweet potatoes without skins, juiced vegetables, and melons.
• Cook your vegetables thoroughly to make them softer and easier to digest.
• Try a digestive enzyme supplement, such as Vegan Bean-Zyme, to help break down high-fibre foods like beans and broccoli.
• Manage your bean intake by watching your portion sizes, rinsing your beans, cooking them thoroughly, or opting for tofu or tempeh instead.
• Gradually increase your fibre intake over time to allow your body to adjust.
• Legumes: Beans, lentils, and chickpeas are excellent sources of fibre and plant-based protein.
• Whole grains: Oats, quinoa, brown rice, and whole-grain bread provide both soluble and insoluble fibre.
• Fruits and vegetables: Avocados, berries, apples, bananas, carrots, broccoli, artichokes, and sweet potatoes are all high in fibre.
• Nuts and seeds: Almonds, chia seeds, and popcorn are great sources of fibre and healthy fats.

Remember, it is normal to experience some digestive changes when transitioning to a vegan diet. However, if reducing your fibre intake does not help with your diarrhoea, it is recommended to consult a physician to rule out any other potential causes.

Zinc deficiency

Diarrhea is a common issue for people transitioning to a vegan diet, and it can be caused by a variety of factors. One potential cause is a zinc deficiency, which is characterised by impaired immune function, loss of appetite, growth retardation, delayed sexual maturation, hair loss, eye and skin lesions, impotence, and hypogonadism in males.

Zinc is an essential mineral that supports various bodily functions, including fighting infections, speeding up chemical reactions, and maintaining a healthy immune system. While it is possible to get enough zinc from a well-balanced vegan diet, some vegans may need more than the recommended daily intake due to the reduced absorption of zinc from plant-based sources.

Phytates, commonly found in plant foods, reduce zinc absorption, and some researchers suggest that this may increase the zinc needs of vegans by up to 50%. As a result, vegans should be mindful of their zinc intake and monitor for potential deficiency symptoms.

If you suspect that your diarrhea is related to zinc deficiency, consider tracking your diet and symptoms to identify any patterns. Additionally, consult a healthcare professional for personalised advice, as they can recommend appropriate zinc supplements or dietary adjustments to address the deficiency.

Food allergies or intolerances

Food allergies and intolerances are a common cause of diarrhea, and they can be tricky to identify. A food intolerance is when you have difficulty digesting certain foods or ingredients, and it can make you feel unwell. Symptoms of a food intolerance usually appear a few hours after eating the trigger food and can last for a few hours or days. It's important to note that a food intolerance is different from a food allergy, which can cause symptoms such as itchy skin, wheezing, or swelling of the lips, face, and eyes.

If you suspect you have a food intolerance, it's best to see a doctor or a dietitian, who may recommend a special diet or a breath test to check for lactose intolerance. Keeping a food and symptom diary can also help identify any triggers. It is important not to cut out foods from your diet without medical advice, as you could miss out on essential vitamins and minerals.

Some common food intolerances include lactose intolerance, gluten intolerance, histamine intolerance, caffeine intolerance, and intolerance to artificial sweeteners. Lactose intolerance is the most common, affecting people who cannot digest lactose, a sugar found in milk and dairy products. Gluten intolerance can cause issues with eating bread and pasta, while histamine intolerance is associated with wine and cheese. Caffeine and artificial sweeteners, often found in fizzy drinks, can also cause issues for some people.

Food allergies can also cause diarrhea, and they are not uncommon in adults and children. Milk, fruits, and spices have been identified as frequent triggers of allergic diarrhea. A person may experience persistent and chronic diarrhea, along with other symptoms such as headaches, allergic fatigue, and toxemia. Skin testing and ingestion tests can help identify food allergies, and a diet excluding suspected allergens is often advised.

If you are experiencing diarrhea on a vegan diet, it is important to consider whether you may have a food allergy or intolerance. Keeping a food journal and tracking your symptoms can be helpful in identifying any trigger foods. Consulting with a healthcare professional is always recommended to ensure you receive proper guidance and treatment.

Small Intestine Bacterial Overgrowth (SIBO)

SIBO can be triggered by various factors, including stress, food poisoning, and issues with the immune system. It has also been linked to gastrointestinal dysfunctions such as low stomach acid, bile and enzyme issues, and migrating motor complex dysfunction (MMC). Intestinal nerve or muscle problems and antibiotic use can also be contributing factors.

Symptoms of SIBO include abdominal pain or discomfort, gas, bloating, and diarrhea. In more severe cases, sufferers may experience weight loss due to vitamin deficiencies. The excess bacteria feed off undigested food, especially carbohydrates, leading to excess levels of hydrogen and/or methane in the digestive system. This can result in intestinal permeability, allowing bacteria and undigested food to enter the bloodstream and triggering heightened immune responses and food allergies or sensitivities.

To manage SIBO, a common approach is to follow a Low FODMAP diet, which refers to Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. This diet details specific foods that may offset SIBO and encourages people to avoid them. The Low FODMAP diet suggests avoiding oligosaccharides like wheat, rye, and garlic, as well as some beans, peas, and chickpeas. Disaccharides, referring to lactose, are also not allowed, but dairy-free vegan milk can be a good alternative. Monosaccharides, or foods that contain fructose in excess of glucose, like apples and pears, should be avoided. Polyols, which are a common cause of bloating and wind, are also not recommended. These include stone fruits like apricots and peaches and foods like celery and mushrooms.

For vegans on the Low FODMAP diet, some good food choices include fruits like strawberries, oranges, and blueberries, vegetables like potatoes, capsicum, and spinach, nuts and seeds like Brazil nuts and sunflower seeds, legumes like firm tofu and brown lentils, grains like brown rice and oats, and beverages like green tea and black tea.

Another treatment option is the Elemental Diet approach, which involves replacing meals with an elemental formula for several weeks to "starve off" the bacteria. Elemental formulas contain all the necessary macro and micronutrients, vitamins, and minerals to sustain life while not feeding the bacteria located in the small intestines.

It is important to note that not all bacteria are harmful, and a vegan diet can be beneficial for those diagnosed with SIBO. Plant-based foods support the growth of "friendly" bacteria, while pathogens prefer diets that lack plant foods and are rich in meat, dairy, and eggs.

If you suspect you have SIBO, it is recommended to seek advice from a medical professional and get a hydrogen breath test, also known as the Lactulose Breath Test, which is the most common test for diagnosing SIBO.

Irritable Bowel Syndrome (IBS)

IBS is not well understood, but it is believed to be associated with a range of bowel symptoms, including diarrhoea, that flare up alongside abdominal pain. While a vegan diet is not a clear solution for those with IBS, it can be followed with the right support and advice from a dietitian.

A vegan diet is typically high in fibre and FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols), which can irritate the gastrointestinal (GI) system and worsen IBS symptoms. FODMAPs are tiny carbohydrates that are poorly absorbed in the intestines, pulling water into the intestine and causing fermentation, gas, bloating, and discomfort. Distension of the gut can also cause diarrhoea.

However, a low FODMAP vegan diet can help manage IBS. This involves eliminating hard-to-digest foods from meals. While this can be challenging, as many vegan staples are high in FODMAPs, it is possible with careful planning to ensure nutritional needs are met. For example, while beans and legumes are a common source of protein in a vegan diet, they are high in FODMAPs and can cause IBS symptoms. However, there are low-FODMAP vegan protein sources, including firm tofu, tempeh, nuts, seeds, and quinoa.

It is important to work with a doctor or dietitian to ensure a low FODMAP vegan diet supports overall health and includes essential vitamins and minerals. A dietitian can help create a structured FODMAP reintroduction plan to determine the best approach for managing IBS.

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