Four Reasons For Bloating on a Vegan Diet

Maybe you’re new to vegan or plant-based eating and have recently started experimenting with different plant-based foods and recipes. Alongside this switch, you may have started noticing that you’re experiencing a lot more bloating than you’re used to. Or maybe you’ve been following a plant-based diet for a while but still seem to be experiencing regular episodes of bloating. 

If this sounds familiar, you are not alone! Bloating is one of the most common digestive symptoms experienced by both new and long-term vegans alike. Although bloating is very common, particularly amongst those in the plant-based community, this doesn’t mean that it is something you just have to put up with. 

Firstly, what is bloating? 

Bloating can best be described as an uncomfortable feeling or increased pressure in your abdomen. This may or may not be accompanied by some visible protrusion (which people may often refer to as a ‘food baby’ or ‘looking pregnant’). 

Bloating vs. distention 

These two terms are sometimes incorrectly used interchangeably, however they aren’t the same thing. 

Bloating is the feeling or sensation of increased pressure. Distension, on the other hand, is the physical swelling of the abdomen. Bloating and distension may coexist or happen independently. 

Bloating may be either: 

1. Continuous – this means it is present throughout the whole day (potentially even from the moment you wake up) with no fluctuations associated with food/meals.
2. Intermittent – this type is much more common and refers to bloating that is triggered after meals or gradually worsens throughout the day. 

If you are experiencing continuous bloating, this is less likely to be able to be managed through food or lifestyle modifications and it may be best to speak with your GP to rule out any red flags. However, if it is intermittent bloating, there are a few handy tips that may be able to help you get things back to normal. 

When is bloating normal?

It should be noted that some bloating and distension are a normal part of digestion, particularly if you have just had a large meal (the food has to sit somewhere whilst it’s being digested)!

However, it is important to differentiate between what is considered ‘normal bloating’ and when this becomes more problematic. If your bloating is starting to cause pain or discomfort to the point where it is impacting your ability to go about your everyday tasks or your overall quality of life, then it may be a good idea to seek professional help. 

Four common reasons for bloating on a vegan or plant-based diet

There are many potential causes of bloating including medical, diet and lifestyle causes. However, in this article, we will be focusing on the main reasons for bloating on a vegan (or plant-based!) diet. 

1: Increased fibre intake 

A plant-based diet is also a high fibre diet. This is because a majority of the staple foods that form the basis of a plant-based diet (such as fruits and veg, beans and legumes, nuts, seeds and whole grains) are all rich sources of fibre.

Therefore, when swapping over from a standard omnivorous diet, you are often typically replacing some staple low fibre foods such as meat, seafood and eggs with plant-based alternatives such as more beans and legumes that are significantly higher in fibre. 

Fibre is a type of carbohydrate that our digestive tract doesn’t digest and absorb like the rest of the food we consume. Instead, it passes undigested into our large intestines where it is fermented by our gut bacteria. During this process, a lot of gas is produced which can cause a feeling of increased pressure or fullness. This is actually a good thing as it means our digestive system is working and we are feeding our good gut bacteria. 

In fact, evidence suggests that the high fibre intake associated with plant-based diets appears to be beneficial for our gut health by promoting a more rich and diverse gut microbiome. 

Whilst fibre carries many health benefits, too much fibre, or even consuming more than you are used to, can cause some uncomfortable side effects such as bloating. Luckily, the bloating associated with increased fibre intake is often not permanent as your gut starts to adapt to digesting the higher fibre load, but it can take some time. This may be anywhere from a few days to a few months. 

There are a few additional tips and tricks to help minimise bloating on a vegan or plant-based diet.

Increasing your fibre intake slowly by gradually increasing your intake of plant-based foods is your best bet to allowing your gut bacteria to get used to the higher fibre load. How much fibre you will be able to tolerate looks different for everyone, so it can take some trial and error.

A few simple tips to help include: 

• peeling and/or cooking fruits and vegetables
• incorporating some lower fibre plant-based proteins such as tofu, soy milk, protein powder and mock meats over opting for legumes at each meal
• swap out some whole grains for more refined varieties such as white rice or white bread 

2: Plant-based diets are often higher in FODMAPs

If you haven’t heard of FODMAPs before or don’t know much about them, you can read more about them in a previous blog post here.

Essentially, FODMAPs are another group of carbohydrates that are poorly digested by our bodies and instead fermented in our intestines. Although this is a normal process, some people are more sensitive than others and this increased gas production can cause significant distension and bloating to the point where it becomes uncomfortable and/or painful. 

In general, plant-based diets are also often rich in FODMAPs. This is because plant-based diets are rich in a variety of grains, fruits, vegetables, nuts, seeds and legumes, many of which are considered to be high in FODMAPs.

When it comes to managing bloating associated with a FODMAP intolerance, often a FODMAP elimination and reintroduction diet is indicated to help you identify what foods are triggering your symptoms and in what amounts you can tolerate them. It includes an elimination, reintroduction (testing) and personalisation phase.

However, the low FODMAP diet has its risks due to excluding a number of foods from the diet and is designed to be completed with dietitian supervision.

Our dietitians at Plant Nutrition and Wellness are trained in implementing the low FODMAP diet.

3: Eating larger volumes of food 

As plant-based foods are typically lower in calories per volume than their animal-based counterparts, often the volume of food you need to eat is increased, particularly if you have high calorie needs. This can mean that the size of your meals may increase significantly once you go plant-based. 

This increases your chances of feeling bloated after a meal in two ways:

1. A larger volume of food may mean a higher fibre load 
2. Once consumed, our food has to sit somewhere whilst it is being digested which can lead to the feeling of fullness or physical distension associated with bloating 

To help alleviate this feeling, there are a few simple strategies you may want to try out. These include: 

• Split up your food intake into smaller meals eaten more frequently throughout the day – this gives your body a smaller load of food to deal with at once 
• Opt for cooked veg over raw to reduce the volume 
• Avoid drinking too much fluid with meals as this will only increase the volume you are ingesting 
• Add in more calorie-dense foods such as nuts and seeds, avocado, olives, coconut and olive oil 

4: Not preparing your beans and legumes correctly

Legumes such as beans, lentils and split peas are arguably some of the most notorious foods for causing gas and bloating on a vegan diet. One of the main reasons for this is that beans contain indigestible carbohydrates (as mentioned previously) which means that they are fermented by our intestines which can cause bloating, especially when consumed in large amounts.  

Luckily, there are a few preparation tips you can try that can make beans and legumes a bit easier on our digestive systems.

If cooking beans from dry:

• Soak in water overnight then discard water and rinse well before cooking (this releases some of the indigestible carbohydrates into the water) 
• Ensure beans are cooked thoroughly until soft
• Try adding a bay leaf or seaweed to your water whilst cooking – both these foods contain enzymes that can further help digest the fermentable carbohydrates 

If using tinned beans: 

• Drain liquid from the tin and rinse well until water runs through clear with no foam/bubbles 

Other potential causes for bloating include: 

• Eating too quickly 
• Not chewing your food well enough 
• Chewing gum 
• Drinking carbonated beverages
• Drinking through a straw 
• Leaving long gaps between mealtimes 
• Wearing tight-fitting clothing 
• Stress, anxiety or poor mental health in general 
• Constipation or other functional gut disorders 
• Food allergies or intolerances 
• Medical conditions such as coeliac disease, inflammatory bowel diseases such as Crohn’s or Colitis, SIBO  

Summary

When it comes to managing bloating on a vegan or plant-based diet, there is no one-size-fits-all approach. Strategies that work to improve bloating are likely going to be different for everyone, based on the triggers for the bloating.

For some, it may be a quick and simple fix such as rinsing your beans more, but for others, it can be a bit more tricky and often requires quite a bit of trial and error.

Speaking with one of our dietitians at The PNW Clinic can help you get to the root cause of what’s triggering your gut symptoms and finding appropriate management strategies. 

This article was written by expert vegan PNW Clinic dietitian Georgia D’Andrea.