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Worst Foods For Leaky Gut: What To Avoid
Updated on November 13, 2023
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Worst Foods For Leaky Gut: What To Avoid
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Leaky gut syndrome is a common digestive problem linked to several health conditions. What you eat and other lifestyle habits may contribute to a leaky gut. 

Worst Foods For Leaky Gut: What To Avoid 2

Can Foods Trigger Leaky Gut Syndrome?

Yes. Eating certain foods can cause a leaky gut and trigger digestive symptoms. Here’s how diet affects your digestion and overall health:

Gut Dysbiosis

Some foods can cause bad bacteria to increase and outnumber the good bacteria in your gut. 

Foods containing antibiotics can also eradicate beneficial gut bacteria. This can cause bad bacteria to take over, leading to gut dysbiosis or gut flora imbalance.

Gut imbalance causes your intestine walls to release a protein called zonulin. Zonulin breaks down your gut lining.3

Increased Intestinal Permeability

Foods containing gluten may also trigger the release of zonulin, especially in people with Celiac disease. This indicates the presence of a leaky gut.

Zonulin increases the permeability of your gut lining, causing its content to leak into your blood.

Increased Stress Levels

Foods that cause your blood sugar to spike may also lead to stress. As your body undergoes a sugar crash, your hormones can lose their balance.

Hormonal imbalance can trigger the release of cortisol, a hormone associated with stress. Chronic stress changes the bacteria in your gut.4 

Bad gut bacteria produce chemicals that disrupt your gut wall. The damage lets large particles (including toxins) across the intestinal barrier.

Gut Inflammation

Foods high in trans fats may cause gut inflammation, especially if you eat too much. These foods may also contribute to your stress.

Since they’re not as easy to digest as carbohydrates, your body will have a harder time breaking them down. Your metabolism will also have to spend more energy storing excess fats.

Some foods also contain harmful substances such as herbicides and pesticides. These chemicals may also cause inflammation in your gut.

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Leaky Gut Foods to Avoid

A healthy diet helps you protect your gut health. Just as there are foods you can eat to heal leaky gut, there are also foods that can trigger it.

Below are some foods you should avoid because they can cause leaky gut: 


Gluten may cause gut inflammation. Studies show it’s linked to leaky gut syndrome.5 It causes your intestine to release zonulin which increases gut permeability.6

Removing gluten from your diet helps restore gut health. It’s present in many foods such as pies, cake, and pasta. The main sources of gluten are:

  • Wheat
  • Rye
  • Barley


When you consume lots of high-sugar foods, it can lead to gut inflammation. Harmful bacteria thrive on sugar. They can outnumber your beneficial bacteria and cause gut imbalance. 

You can keep your gut healthy by avoiding refined sugars and artificial sweeteners. Some examples of sugary foods to avoid include:

  • Soda
  • Sports and energy drinks
  • Pies and cobblers
  • Cakes and pastries
  • Candies and sweets

Dairy Products

About 65% of people in the world have trouble digesting lactose, a sugar found in many dairy products.7 This is usually caused by a lactose intolerance.

Bacteria in your gut digest can help digest lactose if you lack the necessary enzyme (lactase). Unfortunately, this produces toxins that cause gut irritation and unpleasant symptoms.

If you have lactose intolerance, you should avoid these foods: 

  • Milk 
  • Butter 
  • Cheese
  • Ice cream

Soy Products

Soy is a superfood because it contains lots of nutrients, especially protein. Unlike other plants, it provides all the essential amino acids. 

Unfortunately, many soy products are genetically modified or grown using herbicides. You can switch to organic soy products to avoid them. 


Corn is gluten-free. However, research shows that people with gluten sensitivity may react negatively to it. Instead of eating corn, you can eat non-gluten alternatives such as:8

  • Millet
  • Wild rice 
  • Arrowroot
  • Buckwheat 


Lectins are proteins found in many foods. They can bind to your gut lining and disrupt the tight junctions that keep your intestinal walls intact. 

If you have a leaky gut syndrome, you should reduce the lectins in your diet. Some foods that are rich in lectin are:

  • Beans
  • Eggplant
  • Peppers
  • Potatoes
  • Tomatoes

What Is A Leaky Gut?

A healthy gut lining keeps large particles inside your gut from “leaking” into your blood. When you have a leaky gut, the intestinal lining is abnormally porous.1 

This causes toxins, food, and harmful bacteria to cross the gut barrier and reach your blood. 

People with Celiac disease, Crohn’s disease, and irritable bowel syndrome (IBS) tend to have increased gut permeability. Leaky gut is also linked to autoimmune diseases such as:

  • Lupus 
  • Asthma 
  • Arthritis
  • Diabetes 
  • Psoriasis

Leaky Gut Symptoms

Leaky gut symptoms can affect all parts of your body. Signs to look out for are:2

  • Gas
  • Bloating 
  • Diarrhea
  • Indigestion
  • Skin irritation 
  • Fibromyalgia
  • Food allergies
  • Chronic fatigue
  • Seasonal allergies
  • Mental health disturbances 
  • Burning sensation in gut

How to Test For Leaky Gut At Home

If you have symptoms of a leaky gut, you should take an at-home gut test to confirm. Simply order your gut health test kit online and wait for it to arrive. 

You should pick a test that checks for leaky gut syndrome. Once it arrives, follow the instructions to collect your sample and mail it back to the lab.

In a few days, you’ll receive your test results online. They can tell you how your gut is doing, and if there are possible signs of a leaky gut

You may also receive recommendations to improve your digestive health.

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Updated on November 13, 2023
Jennifer Anyabuine
Jennifer Anyabuine
Content Contributor
Jennifer Anyabuine is a content writer with KnowYourDNA. She has a B.S. in Biochemistry. She has been writing for 2 years. Her focus is women’s health, fitness, mental health, and general wellness.
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