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A sudden and relatively extreme change in diet is likely to have an impact on our gut and digestive system. Let’s look at what happens to your gut when you become a vegan, starting with the basics.
Put simply, a vegan diet excludes all products that come from an animal source. It may also be referred to as an exclusively plant-based diet.
Foods that are avoided on a vegan diet include:
There are also sub-types within veganism, such as raw veganism and fruitarianism, that have more exclusions from the diet. However, for the sake accessibility, we'll be focusing on the typical vegan diet for now and its relation to the gut.
The gut is an essential system to consider when it comes to health. It is more than just a place where you digest food; for example the gut is home to around 70-80% of our immune system.1 In addition, it's the gut bacteria and enzymes that help to break down food efficiently into nutrients,2 some bacteria even produce nutrients such as B group vitamins.3 Nutrients are absorbed through the gut wall into the bloodstream for transport and use throughout the body while toxins and waste are excreted from the body via the gut.
The state of the gut is associated with everything from heart disease to obesity, autoimmune disease and even mental health.4 If you want to be your healthiest self, looking after your gut is absolutely vital. So can following a vegan diet be a beneficial move for your overall gut health?
First and foremost, there are some real benefits for the gut when you decide to undertake a vegan diet.
The most well-researched of these advantages are the changes to the gut bacteria in the digestive tract. Research has found that there is a reduction in inflammatory gut bacteria, as well as an increase in the protective species of bacteria.5
This is likely due to the higher fibre content of the average vegan diet. Although all fibre is beneficial, there are some types of fibre that provide better fuel for the good bacteria in the gut, these fibres are known as prebiotics. Prebiotics are found in plant-based foods including apples, pears, legumes and wholegrains. By fuelling the good bacteria in the gut, prebiotics support your healthy gut balance - something pertinent to avoiding any inflammation or gut related disorders from developing.6
A vegan diet can eliminate foods that can be problematic and inflammatory for some. Dairy is one example of a food that can inflame the gut, especially in the case lactose intolerance.7 This inflammation can cause real damage to the gut; by removing it from the diet, the gut has a chance to repair the damage.
It's fair to say there are plenty of gut health benefits from eating plant-based foods, but there are also downsides that may occur when following a vegan diet.
If you already have a pre-existing condition that impacts on the gut, eating a plant-based diet may exacerbate symptoms. For example, people who have irritable bowel syndrome (IBS) often see improvement when removing fibres known as FODMAPs,8 but a vegan diet is generally quite high in some of these fibres, which can lead to IBS and other digestive symptoms worsening.
A vegan diet excludes dairy, making it potentially low in good bacteria in the form of probiotics (typically consumed via fermented diary based products, such as bio yogurt). When you consume probiotics, you maintain the balance of good bacteria in the digestive tract. So a person following a vegan diet may not be replenishing the gut with good bacteria, leading to imbalances and potential health issues.
It's important to remember that any diet can be unhealthy if you don't focus on a wholefoods approach. Simply put: someone eating a vegan diet might eat lots of fruit and vegetables, or they might be picking Oreos, vegan pizza, and Red Bull. If you consume a diet that is full of processed foods, your gut health will feel the effects - vegan or not!
If you follow a vegan diet, here are some simple tips that can support your gut health:
Diet should always come first, but if you aren't able to make the necessary changes to your diet, supplements can help to make up for shortfalls. If you want a gut-supportive supplement regime, consider taking:
Supplements are an easy and effective means of ensuring you're avoiding the potential pitfalls of a vegan diet, which typically include vitamin B12, iron, calcium, zinc and vitamin D. Whatever your reasons for adopting veganism, it may be worth considering some supplementation to give you that piece of mind.
If you'd like to read more about the effect of various diets on your health, as well as find more information on how you can promote good gut health, then select Digestion from the Your health menu above. For more information on supporting your health as a vegan, select Going vegan from the Your goals menu above.
Nothing beats a healthy, balanced diet to provide all the nutrients we need. But when this isn't possible, supplements can help. This article isn't intended to replace medical advice. Please consult your healthcare professional before trying supplements or herbal medicines.
1Vighi, G., Marcucci, F., Sensi, L., Di Cara, G. and Frati, F., 2008. Allergy and the gastrointestinal system, Clinical & Experimental Immunology,153(s1), pp.3-6.
2Cantarel, B.L., Lombard, V. and Henrissat, B., 2012. Complex carbohydrate utilization by the healthy human microbiome, PloS one7(6), p.e28742.
3eBlanc, J.G., Milani, C., de Giori, G.S., Sesma, F., Van Sinderen, D. and Ventura, M., 2013. Bacteria as vitamin suppliers to their host: a gut microbiota perspective, Current opinion in biotechnology24(2), pp.160-168.
4Lynch, S.V. and Pedersen, O., 2016. The human intestinal microbiome in health and disease, New England Journal of Medicine,375(24), pp.2369-2379.
5Glick-Bauer, M. and Yeh, M.C., 2014. The health advantage of a vegan diet: exploring the gut microbiota connection, Nutrients6(11), pp.4822-4838.
6Slavin, J., 2013. Fiber and prebiotics: mechanisms and health benefits, Nutrients5(4), pp.1417-1435.
7He, M., Sun, J., Jiang, Z.Q. and Yang, Y.X., 2017. Effects of cow’s milk beta-casein variants on symptoms of milk intolerance in Chinese adults: a multicentre, randomised controlled study, Nutrition Journal,16(1), p.72.
8Nanayakkara, W.S., Skidmore, P.M., O’Brien, L., Wilkinson, T.J. and Gearry, R.B., 2016. Efficacy of the low FODMAP diet for treating irritable bowel syndrome: the evidence to date, Clinical and experimental gastroenterology,
9Jin, Y., Samaranayake, L.P., Samaranayake, Y. and Yip, H.K., 2004. Biofilm formation of Candida albicans is variably affected by saliva and dietary sugars, Archives of Oral Biology49(10), pp.789-798.
10Willett, W., Manson, J. and Liu, S., 2002. Glycemic index, glycemic load, and risk of type 2 diabetes, The American journal of clinical nutrition,76(1), pp.274S-280S.