Lowest FODMAP Beans – How to include beans in your diet when you suffer with IBS

Welcome to my bean blog, where I look into a common dietary conundrum for those managing Irritable Bowel Syndrome (IBS), especially on a plant-based diet.  That is finding the best lowest FODMAP beans to eat which won’t trigger any symptoms or put you back to square one of a low FODMAP diet.

If you’ve been suffering with IBS for a while, or if you’re newly diagnosed, you may already be familiar with FODMAPs.  This stands for Fermentable Oligo-, Di-, Mono-saccharides And Polyols. These short-chain carbohydrates are known to be difficult to digest and can cause extreme discomfort for people with IBS.  Foods high in FODMAPs can trigger a range of symptoms including bloating, gas, abdominal pain and altered bowel habits. 

A low FODMAP diet is perfectly possible on a vegetarian or vegan diet.  However, it is more challenging, with more thought needed to ensure nutritional balance.  Legumes, including beans and lentils, are a staple in plant-based diets, providing a vital source of protein and nutrients. However, many beans are high in FODMAPs, which can cause huge difficulty and confusion when it comes to planning balanced meals.

The purpose of this post is to clear up the confusion and help you understand which beans have low FODMAP levels and are more likely to be tolerated if you suffer from IBS, and which you should avoid while you’re figuring out your sensitivities.  My goal is to help you maintain a balanced and nutritious (vegetarian or vegan) diet without sacrificing the foods you love. 

All beans contain some FODMAPs in varying amounts, mainly as galacto-oligosaccharides (GOS), part of the ‘O’ for oligosaccharides.  Thay also often contain fructans in higher serving sizes.  These carbohydrates are not well absorbed in the small intestine and end up in the large intestine where they are fermented by bacteria.  This fermentation process produces gas and can lead to bloating, discomfort, and other IBS symptoms.

If this sounds like you, you’ve come to the right place.  Let’s explore the world of beans together and find the best options for a happy gut!

The benefits of eating beans

Beans are a powerhouse of nutrition and offer many health benefits, making them a valuable addition to any diet.  

Including beans in your weekly meal plan can contribute to overall health, supporting everything from digestive health to cardiovascular function.  Here are my top 5 reasons to include beans to your diet:

1. Rich in protein: they provide a fantastic plant-based alternative for vegetarians and vegans looking to fulfil their protein needs.
2. High in dietary fibre: beans are abundant in fibre, which not only helps in maintaining bowel health and reducing constipation, but also aids in regulating blood sugar and cholesterol levels.
3. Aid in weight management: due to the high fibre content, adding beans to your meals and snacks can help keep you full without high calorie content.
4. Source of essential nutrients: such as iron, zinc, magnesium and folate.
5. High in antioxidants: which fight free radicals in the body, potentially reducing the risk of chronic diseases such as heart disease and cancer.

Beans that should be avoided on a Low FODMAP diet

I’ve put together a summary of all the beans that have been tested by Monash University, where the low FODMAP diet was invented.  They regularly test foods for FODMAP levels and retest where necessary.  There are a few beans which are off limits during the low FODMAP diet, which are likely to trigger an IBS episode, especially if you have a sensitivity to galacto-oligosaccharides (GOS).

The following beans are high in FODMAPs and there is no ‘safe level’.  Even a small serving could trigger your IBS.  Try to stay away from these until you’ve completed a low FODMAP diet for 2-4 weeks, or if you already know you are sensitive to certain FODMAPs:

• Borlotti beans
• Broad (fava) beans
• Haricot (navy) beans
• Red kidney beans, boiled, drained
• Soya beans

These beans are high in FODMAPs at even low serving levels as they contain high amounts of GOS, which are part of the oligosaccharide family, and fructans in larger amounts.  Broad beans are a bit different as they are high in fructose in small amounts.

If you don’t have a sensitivity to GOS, fructans or fructose, reintroducing the beans above is possible.  Tolerance levels and sensitivities vary between individuals so you may well be able to eat the above beans even in large amounts without getting any symptoms.

However, it’s important to remember that everyone’s digestive system is unique and tolerance levels can vary significantly. Whilst beans might trigger symptoms for many, others might find they can handle small or larger amounts or different preparations of these beans without trouble. This variability is why working with a Dietitian can be incredibly beneficial.  A Dietitian can help tailor your diet to include beans in amounts suitable for you, monitoring and adjusting based on how your body responds.  

Beans that have a low FODMAP serving

Most beans have a moderate serving size.  This amount is suitable to include for those that are following a low FODMAP diet or know they are sensitive to GOS or fructans, as long as you avoid other foods containing FODMAPs in that meal. 

To make this a little easier to understand in practical terms, I’ve listed the beans with a moderate FODMAP content, which are suitable in portion sizes of up to ¼ cup (about 40 g, or 2 tbsp) below.  If you include just one serve of these in a meal, being strict with FODMAPs from other sources otherwise, you should be able to tolerate them without triggering symptoms.

• Adzuki beans (dried, boiled and canned, drained)
• Black beans (dried, boiled and canned, drained)
• Butter beans (canned, drained)
• Cannellini beans (canned, drained)
• Edamame beans
• Lima beans (dried, boiled, drained)
• Mung beans (dried, boiled, drained)
• Pinto beans (canned, drained only)
• Red kidney beans (canned, drained)

The bar chart below gives a summary of the low, moderate and high serves of Monash tested beans which you can include in a low FODMAP diet in moderation. The beans with the highest low FODMAP serve are edamame beans, canned red kidney beans, cannellini beans. These are all suitable in 75 g portion sizes or higher, which is around half a cup. Half a cup of beans can provide significant amounts of nutrients, including around 7-14 g of protein, as well as 4-7 g of fibre and an array of vitamins and minerals.

The prize for the lowest FODMAP bean goes to the edamame bean, which are young soya beans. Great to add to soups, salads, stir-fries or on their own as a high protein snack. They are particularly high in protein at 14 g in 1/2 a cup and contain all the nine essential amino acids. A true superbean!

Are green beans low FODMAP?

Although they are known as beans, green beans are actually categorised as a vegetable.  This is because their nutrient content is more similar to vegetables than beans.  This is reflected in their FODMAP content too, as they are free from GOS and fructans and high in other FODMAPs, known as polyols.  There are two polyols, sorbitol and mannitol, and green beans contain both.

You can include green beans safely without triggering IBS symptoms if you stick to the recommended serving size of 75 g (15 beans).  You can have a up to 120 g (25 beans) as long as you don’t have any other moderate or high serves of FODMAP foods in the same meal.  Of course, if you already know you aren’t sensitive to polyols, you can include green beans freely in your diet.  Here is a summary of the FODMAP content of green beans:

How to Eat Beans on the Low FODMAP Diet

Because oligosaccharides dissolve in water, choosing canned beans and rinsing well, or boiling dried beans for longer and well rinsing ensures the FODMAP content is reduced.  A lot of FODMAPs will be drained away in the soaking and cooking water.

Therefore, to minimise the FODMAP levels of your beans further, try soaking and thoroughly rinsing dry beans before cooking them.  Some beans can be sprouted, which reduces the FODMAP content even further.  These are delicious in low FODMAP salads or as a side to a cooked meal.

Low FODMAP serve of tested sprouted beans:

• Mung beans, up to 95 g (1/2 cup)
• Kidney beans, up to 25 g (1/6 cup)

While all beans contain some FODMAPs in different amounts, most have at least a moderate serving amount.  It’s a good idea to continue to include beans in your diet as often as is comfortable for you.  This will contribute positively towards your overall health.  There is lots of room for personalisation and experimentation under professional guidance.

Conclusion

Following a low FODMAP diet while managing IBS doesn’t have to mean giving up on beans altogether.  However, it should involve careful selection and preparation of beans, using the lowest FODMAP beans more regularly. I hope this blog has helped you understand which beans to avoid due to their high FODMAP content and which that can be enjoyed in moderation.

While you may need some trial and error to figure out your individual tolerance to beans, understanding the details of FODMAP levels in beans empowers you to make informed choices that can enhance the nutritional quality of your diet without compromising your digestive comfort.

Remember, personal tolerance varies, and reintroducing higher FODMAP beans might be possible with professional guidance. Working with a Dietitian can help you do this safely and effectively, tailoring your diet to your specific needs.

Please let me know if you found this helpful or if you any questions. Sign up to my weekly newsletter for updates and tips for following a low FODMAP diet.