As a Registered Dietitian (and someone who suffers from Irritable Bowel Syndrome), it’s very common to have certain foods produce unwanted symptoms.
When it comes to nuts, in particular, several of my clients have often stated that they get gassy and bloated whenever they include nuts in their diets.
Thus, I wanted to explain the relationship between nuts and their bloating effect.
So, why do nuts make you gassy and bloated? Nuts can make you gassy and bloated because they are high in fiber, which means that your gut bacteria eats some of the fiber and creates gas as a by-product.
Additionally, they are high in phytic acid, tannins, and FODMAPs, which are all components that can irritate your gastrointestinal tract.
While there are different reasons why nuts can make you bloated or gassy, there are equally several solutions to minimize the symptoms once you identify the cause.
Check out my ultimate guide of 11 Foods That Make You Gassy (which also includes 4 foods that prevent gas)
Key Takeaways
- Almonds, cashews, hazelnuts, pecans, and pistachios cause the most gas because they are highest in fiber and/or a certain type of FODMAPs that some people cannot digest properly.
- You can soak nuts for at least 24 hours before eating them to break down the phytic acid and help to prevent digestive issues.
- Ginger, peppermint, or chamomile tea can help ease your symptoms if you feel bloated or gassy after eating nuts.
4 Reasons Why Nuts Make You Gassy And Bloated
The four reasons why nuts make you gassy are:
- Nuts are high in fiber
- Nuts contains phytic acid
- Nuts have tannins
- Nuts are high in FODMAPs
1. Nuts Are High In Fiber
Dietary fiber is a type of carb that your body cannot digest properly. When you eat fibrous food, it goes to your stomach first and then to your intestines, and from there the bacteria eats some of the fiber, producing gas as a byproduct.
When you eat high fiber foods, such as nuts, the bacteria in your gut have to work extra hard to digest it, increasing the production of gas along the way. This ultimately means that you get bloated.
For example, 1 oz of nuts (28 g) has 3.5 g of fiber, representing 14% of the daily intake of fiber.
Most people find it hard to digest when they consume 8-10 g of fiber in a sitting. For those with IBS, they might find that the tolerance is lower around 3-5 g. Once you cross that threshold you might find yourself being gassy and bloated.
However, keep in mind that when it comes to gastric problems you might have a higher or lower tolerance.
2. Nuts Contains Phytic Acid
Another common reason why nuts make you gassy and bloated is because nuts have a component called phytic acid.
Phytic acid is often called an “anti-nutrient”.
It is given this name because it binds to certain minerals (especially iron, magnesium, zinc, and calcium), which prevents its absorption in the body.
In nature, phytic acid plays an important role for nuts. It acts as a defense mechanism to prevent the nut from getting eaten by predators.
Some animals can digest phytic acid entirely.
However, as humans, we can only digest 40-60%, which means some of the phytic acids remains undigested.
So when we consume nuts, the phytic acid that remains undigested reaches our intestines, where it can cause some irritation in our gastrointestinal system producing bloating and gas.
3. Nuts Have Tannins
Besides having phytic acid, another common component found in nuts is tannic acid (or tannins).
These are also referred to as anti-nutrients because they decrease nutrient absorption of nutrients, especially when talking about iron.
While tannins are a potent antioxidant that helps reduce inflammation in the body, for some people, consuming too many high tannin foods (tea, coffee, berries, grapes, and apples) can produce gas and bloat.
4. Nuts Are High in FODMAPs
FODMAPs are short chains of carbohydrates that can produce bloating in people that suffer from Irritable Bowel Syndrome. It stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols.
People with IBS tend to have a more susceptible gastrointestinal tract, meaning that when you consume high FODMAP foods, they reach your intestines and it produces gas. Ultimately this means you get bloated and possibly have diarrhea.
Nuts are high in a type of FODMAPs called galactooligosaccharides (GOS). Some people don’t have the enzyme to digest this component, which means that it gets to your intestines intact, where your gut bacteria ferment it causing gas as a byproduct.
While everyone has a different tolerance, studies recommend staying below 12 g of GOS to avoid gastrointestinal complications. For example, according to the MONASH App, this means consuming no more than 30 g of cashews.
Related Article: 15 High-Calorie low FODMAP Foods
Types of Nuts That May Cause More Bloating & What To Avoid
First, determine what is giving you bloating.
Is it the fiber?
To know if you are getting bloating due to high fiber foods, then other foods that are high in fiber will give you the same reaction. For example, if chia seeds, flax seeds, and non-starchy veggies give you bloating, then it’s probably due to a high fiber intake.
Is it the phytic acid?
If other high phytic acid foods like beans, sunflower seeds, sesame seeds, and wheat germ are getting you bloated, then it means that you are sensitive to phytic acid.
Is it the tannins?
If you get bloated while drinking tea, coffee, wine, berries, and apples it means that you are sensitive to tannins.
Is it the GOS?
Finally, if you have been diagnosed with IBS or find that other high FODMAP foods like dairy, legumes, and gluten products are giving you bloating, then you need to reduce your intake of GOS.
Second, avoid these types of nuts.
- If you are getting bloated due to fiber avoid: almonds, pistachios, hazelnuts, and pecans.
- For those that have problems with phytic acid avoid: almonds, walnuts, and brazil nuts.
- If you are getting bloated due to tannins avoid: pecans.
- If you have IBS, avoid those high in GOS like: almonds, cashews, pistachios, and hazelnuts.
Third, understand the content in each type of nuts.
The following table has a summary of the fiber, phytic acid, tannins, and GOS found in different nuts.
I categorized them has having low, medium, or high contents of each.
Depending on how severe you find your bloating, you may be able to consume some of the nuts in the ‘medium’ category, but definitely try and avoid the ones in the ‘high’ category.
Nuts | Fiber | Phytic acid | Tannins | GOS |
---|---|---|---|---|
Peanuts | Medium | Medium | - | Low |
Almonds | High | High | Medium | High |
Walnuts | Medium | High | Medium | Low |
Cashews | Low | Medium | Low | High |
Brazil nuts | Medium | High | Low | Low |
Pistachios | High | Medium | Medium | High |
Hazelnuts | High | Low | - | Medium |
Macadamia | High | Medium | Low | Low |
Pecans | Medium | Medium | High | Low |
Pine nuts | Low | Low | Low | Low |
How To Relieve Stomach Pain After Eating Nuts
If you are bloated and are looking for ways to reduce that pain you are feeling, here are the top remedies I often give my clients (and as someone with IBS have tried myself) to reduce any bloating after consuming nuts.
- Ginger tea. Ginger seems to increase the motility of the gastrointestinal tract, which means that it can speed up digestion. If you want to have an extra digesting boost, add some lemon to your tea. I can assure you it’s the ultimate debloating remedy.
- Peppermint tea. Peppermint seems to help soothe gastrointestinal problems. In animal studies, it’s been noted that it can reduce stomach spasms.
- Chamomile tea. Not only can it work to relax you and give you a good night’s sleep, but it can also decrease your bloating after a meal.
Ways To Avoid Getting Gassy And Bloated From Nuts
Soak Nuts
One way to avoid getting bloated is to soak nuts for at least 24 hours. This tricks the nut into thinking that it is time to germinate, which means that the phytic acid begins to break down so that a plant can grow.
Once you soak them, you can pat them dry and store them to have them ready to eat for the next 2-3 days. Make sure to follow this exact process anytime you want to prevent bloating from nuts.
According to nutritionist Lisa Richards, soaking nuts to remove the phytic acid content can also help to improve nutrient absorption from other foods:
“Soaking seeds and nuts can reduce the phytic acid content in them. By reducing this compound, the nutrients found in seeds and nuts, along with nutrients from other foods we consume, are more readily absorbed without being blocked.”
Pick Low FODMAP Nuts
While most nuts are avoided during a low FODMAP diet, there are some nuts that you can consume. Pick those that are low in FODMAP (at least for the next 4 weeks) to give your GI a rest.
The nuts that are okay to have are brazil nuts, chestnuts, tiger nuts, peanuts, pecans, pine nuts, and walnuts.
If you don’t know which foods to remove to make your bloating better, as a Registered Dietitian, you can book a call to guide you in making your GI feel better by using low FODMAP foods.
Do A Nut Detox
For those getting bloated frequently, I would advise avoiding any nut for at least four weeks, which gives your GI enough time to heal. Once you eliminate them for at least four weeks, you can start adding them slowly and one at a time.
For example, start by adding 10 g of almonds and check if you have any symptoms. If you don’t have any symptoms, you can increase them to 20 g until you find your tolerance.
Repeat this with every one of the nuts to check which ones you can eat in larger quantities.
Decrease Your Nut Intake
If you find it too hard to decrease your nut intake for four weeks, you can decrease the consumption that you are having.
I would recommend not having more than 1 oz (28 g) daily and checking if any symptoms arise. If you still have symptoms with this amount, then decrease it by half.
Frequently Asked Questions
Why Do Almonds Make Me Bloated?
Almonds are high in all the components that make you gassy: fiber, phytic acid, and tannin. These components don’t digest optimally in the stomach and can be particularly challenging for people who experience Irritable Bowel Syndrome.
Can Nuts Cause Digestive Problems?
Yes, nuts have two components called phytic acid and tannins. Not only can they reduce the absorption of nutrients, but they can cause some irritation in your stomach (promoting bloating and gas).
To reduce the chances of digestive problems, soak them for 24 hours before consuming them.
Why Do Nuts Make Me Fart?
Nuts are high in fiber, tannins, and phytic acid. High-fiber foods can make your gut bacteria ferment, creating gas as a byproduct. This means that you are more likely to fart.
Can Nuts Cause Smelly Gas?
Yes, high-sulfur foods like eggs, nuts, and cruciferous vegetables (cauliflower, broccoli, and cabbage) can cause smelly gas. Not only can they promote smelly gas, but they can also increase the frequency with which you get it.
While not everyone has this reaction to sulfur, some people might find it annoying.
Do Cashews Cause Gas?
Cashews can cause gas because they are high in FODMAPs, a carbohydrate that is hard to digest and can upset the stomach. They are also high in fiber, which can make you feel bloated because your body does not digest it.
Do Chestnuts Cause Gas?
While chestnuts are considered low-FODMAP food, an 84 g serving contains 4.3 g of fiber. This high fiber content can cause gas if you are not used to consuming a lot of fiber.
Do Pecans Cause Gas?
Pecans are one of the nuts that can cause the most gas because they are higher in fiber (~3 g per 1 oz). They are also high in tannins, a chemical compound found in nature.
The tannins in pecans can cause gas and bloat in certain people, especially when combined with other high-tannin foods like grapes or coffee.
Do Walnuts Cause Gas?
Walnuts generally don’t cause a lot of gas because they are lower in fiber (2.5 g per 1 oz) than other nuts. However, you may experience gas if you eat more than one ounce of walnuts a day.
Some people also experience digestive issues because walnuts contain a lot of fat (18.5 g per 1 oz) and phytic acid.
Other Foods That Can Make You Gassy & Bloated
- Does MCT Oil Cause Bloating, Gas, & Constipation?
- Can Eggs Make You Gassy & Bloated?
- Broccoli Makes Me Gassy & Bloated
- Oatmeal Makes Me Gassy & Bloated
- Coffee Make Me Gassy & Bloated
- Garlic Make Me Gassy & Bloated
- Salad Makes Me Gassy & Bloated
- Peanut Butter Makes Me Gassy
- Almond Milk Makes Me Gassy & Bloated
- Popcorn Makes Me Gassy & Bloated
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