Confused about soy products and the low FODMAP diet? You’re not the only one! Soy beans and soy products can contain high levels of oligosaccharides (mainly GOS but sometimes fructans). However, it’s a myth that you need to avoid all soy products while on the low FODMAP diet. Manufacturing processes can greatly reduce the FODMAP content of soy products, which is why some are low FODMAP and others are not!
Low FODMAP Soy Options
Soy Milk Made From Soy Protein
Soy milk made from soy bean protein is low FODMAP and it is a great option if you are looking to replace cow’s milk (1). However, be aware that whole soybean milk is high FODMAP, so you will need to check the ingredients list to see if the milk is made from just soy protein. According to Monash University soy milk made from soy protein is safe to have in 250ml (or 1 cup) serves FODMAP (1). Soy milk made from soy protein is much easier to find in New Zealand and Australia.
Firm tofu is made from curdling fresh soy milk and pressing the curds into block moulds (2). It is commonly known that soybeans are high FODMAP, so you might be wondering why firm tofu is low FODMAP. We know that FODMAPs, especially GOS and fructans, are water-soluble (3). During manufacturing firm tofu is pressed, which reduces the water content and drains out some of the GOS (galacto-oligosaccharides), making it low FODMAP (3). The firmer the tofu is, the less water content it has, and in theory the lower in FODMAPs it will be. Just remember to drain your regular tofu well. According to Monash University, a low FODMAP serve of firm tofu is 170g (1).
Please note that silken tofu is high FODMAP and you will need to avoid it during the low FODMAP phase of the diet.
Tempeh is made from cooked soy beans that have been slightly fermented (4). The fermentation of the soy beans reduces the FODMAP content down to levels within the low FODMAP threshold (5). Tempeh is firmer and more flavourful than tofu and it has a slightly nutty taste.
Miso paste is a staple in Japanese cooking and is made from fermented soy beans (6). Miso paste is low FODMAP in 12g (2 sachet) serves (1).
Soy sauce is made using fermented soybeans. It is possible that the fermentation process reduces the oligosaccharides in the soybeans, which is why the soy sauce is low FODMAP. Soy sauce is low FODMAP in 2 tablespoon serves (1).
Fresh Edamame (1 cup or 50g)
Edamame are young (immature) green soy beans that are eaten fresh, unlike the hard, dry mature soy beans which are used to make tofu and soy milk. The edamame beans (just the beans not the pods) are low FODMAP in serves of 1 cup (50g). If you are not sure how to use edamame beans then check out my Low FODMAP Asian Hot & Sour Soup, which was published by Monash University in 2016.
Soybean oil is highly processed and does not include any carbohydrate content. This means it is low FODMAP, along with all other oils.
Soy lecithin is made during the production of soybean oil. It consists of a mixture of fat and oil (not carbohydrates), which means it is considered low FODMAP, although it hasn’t officially been tested by Monash University. Also keep in mind that only small amounts of soy lecithin are used in processed products, which makes it unlikely that it will increase the overall FODMAP level within the products. You can find out more about soy lecithin here.
FODMAP Content Varies
Soy Protein Powder
Soy protein powder is made from defatted soybean flakes that are processed to remove some of the oligosaccharide content. According to Monash University, soy milk made from soy protein is low FODMAP (1). So it is possible that some soy protein powders might be low FODMAP, however, that will depend on how it has been processed. More testing is still needed to understand the FODMAP content in soy protein powders. In the meantime, if you do decide to use soy protein powder, choose soy protein isolate powder that contains low amounts of fibre or no fibre content (the oligosaccharides hide in the soybean fibre), then test your tolerance to a small serve.
The FODMAP content of soy yoghurt is likely to vary depending on the type of soy milk used. Ideally look for a soy yoghurt which is made from soy protein, otherwise you might want to test your tolerance levels to a small serve first.
High FODMAP Soy Products
Silken tofu is unpressed, which means, unlike regular tofu, the water and FODMAP content is not drained out of the tofu. According to Monash University silken tofu is high FODMAP for GOS (oligosaccharides) (1).
Are you ready to take control of your gut symptoms?
No thanks, my gut is perfect.
Soy Milk made from Whole or Hulled Soy Beans
Soy milk made from whole or hulled soy beans have higher levels of FODMAPs compared to soy milk made from soy protein. These milks are generally considered high FODMAP, however, you can enjoy a small 60ml serve of soy milk made from hulled soya beans, or a 30ml serve of soy milk made from whole soya beans (1).
Boiled soy beans (these are mature soy beans) are high FODMAP for both GOS and fructans at small ¼ cup serves (1). This means it is advised that you avoid them during the low FODMAP phase.
Soy flour is popular in gluten free products. It has been tested by FODMAP Friendly and it is high FODMAP for fructans and GOS in 50g serves. This means you should avoid large serves during the low FODMAP phase of the low FODMAP diet. You might find you can tolerate 1 to 2 slices of gluten free bread that contains soy flour, providing it isn’t the predomination flour (eg listed in the first 3 ingredients), so it can be worth exploring your tolerance levels.
Just remember that the low FODMAP diet is not a soy free diet! You can enjoy a range of soy based products like soy protein milk, regular tofu, tempeh, soy sauce, miso, and edamame. Just remember to check the Monash Low FODMAP app and FODMAP Friendly App for serving size guidelines.
Natalie saysAugust 26, 2018 at 2:39 am
I’ve been trying to find out whether TVP/soy curls are low FODMAP… Can’t figure it out. Does anyone have any ideas?
Alana Scott saysAugust 26, 2018 at 7:24 am
According to Monash University Low FODMAP app, TVP is high FODMAP at 1 tablespoon. This means you will need to avoid it while you are in the strict phase of the low FODMAP diet. You can look at reintroducing it once you have tested your tolerance to GOS and fructans.
Martha saysOctober 22, 2018 at 2:23 am
Is silk soy milk made from soy protein or soy beans?
Alana Scott saysOctober 22, 2018 at 5:55 am
I’ve just had a look at it looks like Silk Soy Milk is made from whole soybeans. This means we would recommend avoiding it during the first phase of the low FODMAP diet and then testing your tolerance levels to it.
Elizabeth saysDecember 8, 2018 at 10:42 pm
Does anyone know of a soy milk commonly available in the US that is made from soy protein?
Alana Scott saysDecember 10, 2018 at 7:20 pm
I know that 8 Continent Soy Milk is low FODMAP and available in some parts of the USA – it might be worth seeing if it is available near you: http://www.8thcontinent.com/products/original/
Tam saysJanuary 23, 2019 at 9:53 pm
In terms of these serving sizes, are they based on having just that product on its own. Or do they remain the same when combined. For example if I was making ramen with soy sauce, tofu and miso would I follow portion guidelines, or would they need adjusting given I’m using different soy products?
Alana Scott saysJanuary 25, 2019 at 1:37 am
Those three soy based options should be fine to combine together providing you follow portion size guidelines and choose firm tofu. If you’re not sure how to combine different items you can always check the Monash app and see if they become high FODMAP for the same FODMAP group at a larger serve – if they do then you would need to take a bit for care if your symptoms weren’t settling.
Manu saysJanuary 20, 2020 at 12:52 am
Okara is low in fodmap ?
Alana Scott saysJanuary 20, 2020 at 2:00 am
Thanks for leaving a comment. I’ve just been looking into okara for you. Right now this hasn’t been tested for FODMAPs, however as it is made from the insoluble parts of soy beans that are leftover after making tofu or soy milk we are going to assume that it will be high FODMAP. We suggest you test your tolerance levels to okara once your symptoms are settled.
Mélanie Perron saysJune 5, 2020 at 9:48 pm
What about soy butter? It’s a great replacement for peanut butter when you’re allergic but there’s almost no info on it 🙁
Alana Scott saysJune 6, 2020 at 10:08 pm
Thanks for leaving a comment! Okay so right now soy butter is most likely high FODMAP. The soy butter is made from whole roasted soybeans and we know that boiled soy beans are high FODMAP. That means our recommendation is to avoid the product until your symptoms are settled, then you can test your tolerance to a small amount.
Rebecca Krebs saysAugust 24, 2020 at 12:20 pm
Do you know if soy flakes and pops are high in fodmap, especially anything other than GOS (which I can tolerate)?
I haven’t found anything about those.
Thanks so much!
Alana Scott saysSeptember 21, 2020 at 4:04 am
Thanks for commenting! Okay so soy flakes and pops are currently untested for FODMAPs. Our gut feeling is that these are likely to be high FODMAP for GOS and potentially for fructans too. We’d suggest you test your own tolerance to these products once your symptoms have settled. This article gives you some advice on how to do this: https://alittlebityummy.com/can-i-eat-this-testing-your-fodmap-tolerance-to-untested-foods/