Is soy low or high FODMAP? Soy products discussed.

If you are following the low FODMAP diet, you may find yourself asking, “Is soy low or high FODMAP?”. 

In this article, we look at the low FODMAP diet and specifically whether soy is FODMAP friendly. 

We discuss the different types of soy products such as tofu, soy milk, and soy protein and look at their individual FODMAP content. 

 Soy makes up part of a well-balanced diet, and its nutritional value is explored below.

What is the low FODMAP diet? 

The low FODMAP diet is a diet which is low in ‘FODMAPs.’

This low FODMAP diet helps to identify if you have any food intolerances as part of your IBS. A structured reintroduction phase then follows the initial restriction phase of 4-6 weeks.

To find out more, read our article, Irritable Bowel Syndrome & Low FODMAP diet. 

You can also check out this Low FODMAP grocery list + meal plan (dietitian approved) if you are already following the low FODMAP diet.

What is soy?

Soy, also known as soybean or soya bean, is a type of legume native to East Asia (3). 

You can enjoy soy in its original form, the food industry also uses it in multiple food products such as tofu, soy milk and soy yogurt. 

What are the nutritional benefits of soy?

Soy can make up part of a well-balanced diet and is rich in several nutrients, including protein.

Soy is high in protein. Unlike other plant proteins, soy is a complete protein, meaning it contains all the essential amino acids (the building blocks of protein) the body needs (4). 

In addition to being rich in protein, soy is a great source of B vitamins and minerals such as potassium and magnesium.

Soy is also high in fiber and counts towards one of your 30 plant points per week (5).  

This is a concept backed by research where eating 30 different types of plants per week is good for gut health (6). 

Is soy high or low FODMAP?

Unfortunately, regular soybeans are not low FODMAP.

Monash (the University which tests foods for FODMAP content), says that soy is high in FODMAPs at as little as ¼ cup (7). 

Soy is high in the FODMAPs galacto-oligosaccharide (GOS) and fructans (7). 

Edamame beans, which are immature soybeans, contain fewer FODMAPs and are a good low FODMAP alternative to soybeans.

You can enjoy edamame beans at a low FODMAP portion of 90g (7).

Are soy products high FODMAP?

Read below as we discuss various soy products and whether they are suitable for a low FODMAP diet.

Is Tofu ok for the low FODMAP diet?

Tofu is a soft and pale high protein food product made from mashed soybeans and is often a staple in vegetarian and Asian diets (8).

You can enjoy firm tofu on the low FODMAP diet, but do note that silken tofu is high FODMAP (7).

Is Tempeh low FODMAP?

Tempeh is made with soybeans, so you may think it is high FODMAP.

However, tempeh is low FODMAP. This is due to the process in which it has been made. In this process, soybeans are firstly soaked (reducing FODMAP content).

The soaked soybeans are then fermented using bacteria. This process reduces the FODMAP content (9).

Is Soy Milk low FODMAP?

You may be surprised to hear that the FODMAP content of soy milk depends on whether the milk uses whole soybean or isolated soy protein. 

Soy milk made from soy protein has been tested as low FODMAP.

Soy milk made from the whole soybean is high FODMAP and you can only enjoy it in small quantities between 30-40mls which is enough to enjoy a cup of tea. 

It is derived from hulled soybean can be enjoyed in slightly larger quantities, being low FODMAP at 60mls. 

Soybean hulls are a hard, fibrous outer coating on the soybean, when this is removed it slightly reduces the FODMAP content (10). 

The most common type of soy milk available is, unfortunately, soy milk made with the whole bean. 

However, if you live somewhere where there is a wider selection of products you may find a suitable soy milk.

Sweetened soy milk varieties can increase the amount of fructose (a FODMAP) and so it is best to avoid these  or enjoy them in small quantities (7). 

For more milk options to enjoy on the low FODMAP diet, see our blog on Low FODMAP milk options.

Is Soy Yogurt low FODMAP?

Unfortunately, soy yogurt is low FODMAP at a mere 2 tablespoons and moderate in FODMAPs at ¼ cup (49g). 

At 140g (1 pot), soy yogurt is high in FODMAPs, including GOS and fructans (7).

We recommend sticking to the low FODMAP portions while following the low FODMAP diet, depending on individual tolerance. 

For more information on low FODMAP yogurt, see our article, Can you buy low FODMAP yogurt?.

Is Soy Protein low FODMAP?

Soy protein is regularly used as a substitute in meat alternative products.

Despite being a great source of protein, soy protein is sadly high FODMAP and therefore not suitable on the low FODMAP diet.

This includes textured vegetable protein that is soy protein based, soy mince and soy ‘chicken’ strips. 
You can enjoy soy chicken strips and soy mince in small quantities. See the Monash app for details (7).

Is Soy Flour low FODMAP

Soy flour is made directly from grinding down soybeans. It is therefore high FODMAP and you should avoid it. 

Take a look at our Low FODMAP flour + high FODMAP flour list for more information on suitable flours.

Is Soy Sauce low FODMAP?

Soy sauce is made using a fermentation process.

During this process, FODMAPs are destroyed. This makes soy sauce safe if you are on the low FODMAP diet. 

For more information and recipe inspiration for soy sauce, see our article, Is soy sauce low FODMAP?

Are Soy Curls low FODMAP

Soy curls are made by boiling and dehydrating soybeans and are used as a plant-based meat alternative.

Testing the FODMAP content of soy curls is not done, however we can assume they are high FODMAP as they are made from dried soybeans.

Therefore, you should  avoid soy curls while following the low FODMAP diet.

Are Soy Crisps low FODMAP? 

Again, soy crisps have not been tested for their FODMAP content, but it is likely that they are high in FODMAPs as they are made from soybeans and may even have additional high FODMAP flavorings.

Summary

Soy (i.e. soybean) is not low FODMAP and you should try to avoid this during the restriction phase of the low FODMAP diet. 

However, you can enjoy some soy-derived products while on a low FODMAP depending on how the product is processed and its portion size. 

As with other foods, checking your portion sizes while following the low FODMAP diet is always important.