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Worst Foods for Gut Health — Foods to Avoid for a Healthy Gut

Updated on April 22, 2022
Written by
Kelly Jamrozy
2 sources cited
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Your gut is an important part of your body. It is responsible for digesting food, absorbing nutrients, and eliminating waste. It also supports immune function and protects you from disease.

The gut is a very complex organ and scientists are still learning a lot about it. However, we do know that there are foods to improve your gut health.

In this article, we’ll instead talk about the worst possible foods for your gut.

Why You Need to Keep Your Gut Healthy

The gut is considered the body’s "second brain”. This is because it plays a role in overall health and well-being.

Here are some reasons why gut health is important:

  • The gut houses over 70 percent of the body’s immune system
  • It’s home to trillions of gut bacteria which help digest food and absorb nutrients
  • Your gut microbiome is involved in regulating mood and stress
  • A healthy gut reduces your risk of many chronic diseases, including diabetes and inflammatory bowel disease
  • Promotes hormonal balance

Improving your gut health is one of the best things you can do for your health. In addition to having fewer digestive problems, you’ll feel better in general.


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Foods That Are Bad for Your Gut Bacteria

Your gut is home to trillions of bacteria, both good and bad. This microbiome is essential for keeping your digestive system functioning properly. 

There needs to be a balance of healthy gut bacteria. Unfortunately, poor dietary choices can lead to an imbalance in the gut flora. 

Some foods can increase harmful gut bacteria. Others can decrease the beneficial bacteria in your gut.

If you want your good gut bacteria to thrive, below are some foods you should limit or avoid. The same foods can treat small intestinal bacterial overgrowth (SIBO).

1. Alcoholic drinks

According to Gut Microbes, drinking a lot of alcohol is associated with dysbiosis. Gut dysbiosis occurs when the bacteria in your digestive tract is out of balance. 

This can lead to different health issues, including:

  • Acid reflux
  • Anxiety
  • Chronic fatigue
  • Constipation
  • Cramps
  • Diarrhea
  • Gas and bloating 
  • Skin disorders, including acne, psoriasis, and rashes

If you want to drink alcohol, do so in moderation and only occasionally.

2. Artificial sweeteners

We all know that artificial sweeteners are much sweeter than regular sugar. But did you know that they can also make gut bacteria imbalanced?

There is a type of gut bacteria called "Clostridium" which thrive on sugar. When we eat artificial sweeteners, these bacteria consume them and produce toxins that can make us sick.

This is why it's important to be aware of the types of artificial sweeteners we're consuming. 

Common artificial sweeteners to watch out for include:

  • Splenda Naturals Stevia Sweetener and Truvia (stevia)
  • Splenda (sucralose)
  • Sweet'N Low, Sugar Twin, and Necta Sweet (saccharin)
  • Sunett (acesulfame K)

Aspartame is another sweetener with negative effects on gut bacteria.

3. Red meats

Red meat can be bad for healthy bacteria. Research shows that high beef consumption negatively impacts gut microbiota.

Red meat is high in saturated and trans fats, which can promote the growth of bad bacteria. It is often cooked at high temperatures, which can destroy beneficial bacteria.

Examples of red meat include:

  • Beef
  • Pork
  • Lamb
  • Venison
  • Boar
  • Rabbit

4. Processed foods

A diet rich in processed food is bad for gut bacteria. The overuse of antibiotics in livestock, as well as the use of herbicides and pesticides, can disrupt the delicate balance of gut microbes. 

This can lead to problems like antibiotic resistance and inflammatory bowel disease.

Processed food also tends to be high in sugar, which can feed harmful bacteria. In addition, many processed foods are low in fiber, which is important for a healthy gut.

Additionally, a diet high in processed food can also cause weight gain. This puts additional strain on the gut.

Examples of processed foods include:

  • Deli meats
  • Cereal
  • High-sugar drinks
  • Prepacked and frozen foods
  • Microwavable meals
  • Instant noodles

5. Sugary soft drinks

The sugar in soft drinks and soda feeds harmful bacteria in the gut.

Research shows the consumption of artificial sweeteners is linked to negative changes in microbiome activity. In addition, sugary drinks can also contribute to weight gain, which can further impact gut health.

6. Foods with antibiotics

Antibiotics target all bacteria, good and bad. This means when you introduce them to your gut, they wipe out all of the good bacteria.

This happens when you’re taking antibiotic medication, but they can also get into your gut when you eat foods treated with antibiotics. This includes meats and dairy products that come from animals treated with antibiotics or given feed containing them. 

Foods Bad for Leaky Gut

A leaky gut is a condition in which the lining of the intestines becomes damaged. This causes bacteria and toxins to "leak" into the bloodstream. It can lead to inflammation, autoimmune disease, and other health problems.

If you’re not sure, you can always take a leaky gut test to find out.

Certain foods can treat a leaky gut and restore your digestive health. But there are also foods you need to avoid to reduce symptoms. These are:

1. High-lactose dairy products

Approximately 65 percent of the human population struggles with lactose intolerance. They don't have enough of lactase, an enzyme needed to properly break down lactose. 

High-lactose dairy can cause leaky gut in people with lactose intolerance. You can take a food intolerance test to see if you have it.

High-lactose dairy foods include:

  • Whole Milk
  • Ice cream
  • Butter
  • Cheese

2. Non-organic foods

Fruits and vegetables that contain pesticides are considered non-organic foods. Eating them may cause inflammatory gut bacteria to thrive.

Switching to an organic diet is one of the best ways to improve gut health naturally. Organic food is free of harmful pesticides and chemicals that can disrupt the delicate balance of the gut microbiome. 

3. Foods high in gluten

Gluten-rich foods contain lectins, which can cause leaky gut symptoms. This is especially true for people with gluten intolerance.

Foods high in gluten include:

  • Bread
  • Baked goods
  • Cereal
  • Pasta
  • Crackers
  • Beer
  • Gravy
  • Commercial soups

4. Allergenic foods

Food allergies cause intestinal damage and inflammation, which can lead to a leaky gut. It’s important to note that not all people with food allergies will develop a leaky gut.

Foods that are common allergy triggers include:

  • Peanuts
  • Milk
  • Eggs
  • Chocolate
  • Wheat
  • Soy
  • Shellfish

5. Corn

Corn is a gluten-free product. However, peptides from maize prolamins could induce a celiac-like immune response.

Researchers believe it could be responsible for persistent mucosal damage in a very limited subgroup of Celiac patients, making corn harmful for people with the disease. 

6. FODMAP foods

FODMAP stands for:

  • Fementable
  • Oligosaccharide
  • Disaccharides
  • Monosaccharides
  • Polyols

People with irritable bowel syndrome (IBS) should avoid these foods. Examples of FODMAP foods include processed foods, fruit juices, sweeteners (like agave and honey), condiments, jam, relish, and hummus.

Foods That Are Bad for Gut Health

A healthy digestive system is important for many reasons. First, it helps the body absorb nutrients from food. It also gets rid of waste products that the body doesn't need.

Finally, a healthy digestion ensures overall health by preventing harmful bacteria and toxins from getting into the bloodstream.

To keep your digestion healthy, here are foods you should avoid:

1. Fried foods

Fried foods contain harmful chemicals that can damage the lining of your gut..

They also tend to be high in salt, which can promote the growth of harmful bacteria in your gut. This can lead to infections and other digestive problems.

Some fried foods include:

  • Mozzarella sticks
  • Doughnuts/beignets
  • Samosas
  • Fried chicken
  • Deep fried food

2. Refined grains

There are a few reasons why refined grains are bad for gut health.

For one, they lack the fiber that keeps our digestive system moving. They also tend to be high in sugar and other simple carbohydrates, which can feed harmful bacteria.

Finally, many refined grain products contain additives and chemicals. They can further damage the gut lining and disrupt the delicate balance of good and bad bacteria.

Examples of refined grains include:

  • White bread
  • White flour
  • De-germed cornmeal
  • Instant grains
  • Fruit juices
  • Refined starches

Taking Probiotics for Gut Health

Eating gut-healthy foods is just as important as staying away from foods that are bad for your gut. It’s because these foods:

  • Reduce helpful bacteria 
  • Cause bad bacteria to proliferate
  • Lead to poor digestive health

Alternatively, you can take probiotics to improve your digestion. Probiotics are natural supplements containing beneficial gut bacteria.

Companies like Ombre provide personalized probiotics as well as gut health testing. They can test for gut imbalances and suggest a probiotic blend that best suits you.

Ombre also offers dietary recommendations so you’d have a healthier gut.


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Kelly Jamrozy
Kelly Jamrozy
Content Contributor
Kelly has experience working with clients in a variety of industries, including legal, medical, marketing, and travel. Her goal is to share important information that people can use to make decisions about their health and the health of their loved ones. From choosing the best treatment programs to improving dental and vision health to finding the best method for helping anyone who is struggling with health issues, she hopes to share what she learns through informative content.
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