The 3 Worst Foods for Your Gut: Here’s What to Avoid on a Gut Healing Diet


Our gut microbiome houses trillions of ‘good’ bacteria known as gut flora, which keep our immune system functioning effectively, promote proper digestion, regulate mood, and energize us. We need a diverse population of these beneficial bacteria to efficiently cleanse the body of toxins and harmful bacteria. Aside from factors such as sleep deprivation and chronic stress, excess processed food consumption overtime has been linked to major gut health disturbances. In fact, research has linked ultra-processed food consumption to an Imbalance in the gut microbiome, a reduction in the diversity of beneficial bacteria, weight gain, and obesity. 

The problem with ultra-processed food

Unprocessed or minimally processed foods are whole foods with their nutrients intact.  On the other end of the spectrum, ultra-processed foods are manufactured products created by extracting various substances from food including; hydrogenated fats, sugars, and starches. Having undergone large amounts of processing, these foods lack any significant nutritional value and often contain additives such as artificial coloring and flavoring. Additionally, food that has undergone substantial processing eliminates important nutrients required for optimal gut health. Fiber for example, is a key nutrient that provides prebiotics to our gut in order to support the growth of beneficial bacteria. However, fiber is removed during the manufacturing process of many pre-packaged food products and is replaced by processed forms of sugar (refined sugar).  

How does refined sugar contribute to gut disturbances

Refined sugar is made by extracting natural sugar from sugar cane or sugar corn and is often added to processed foods–Ie. store-bought sweets such as cookies and pastries. However, processed carbohydrates such as refined sugar decrease the availability of good bacteria. They also have been known to increase intestinal permeability and contribute to what is known as “leaky gut syndrome.” The more permeable the intestinal wall becomes, the easier it is for toxins and harmful bacteria to leak through the lining of the gut wall. Fatigue, bloating, food sensitivities, and constipation are all signs that gut permeability may be compromised. 

What is a gut-healing diet?

By regularly incorporating a variety of whole foods including whole grains, veggies, fresh fruit, and legumes into our diet while avoiding ultra-processed forms we can optimize our gut health. Foods in their natural state are unprocessed and contain many important nutrients including fiber, vitamins, and minerals natural state which help sustain the integrity of the gut wall lining. As noted by F45 Sport Nutritionist Kim Bowman, the most effective way to improve gut health is to first eliminate highly processed foods. A gut-healing elimination diet can be utilized to support weight loss and restore a diverse and healthy gut microbiome. We’ve outlined below a few foods to stay clear in order to optimize gut health: 

Processed carbohydrates

  • Candy (contains high-fructose corn syrup)
  • White sugar (sucrose)
  • White bread 
  • Sugary breakfast cereals
  • Granola bars
  • Potato or corn chips
  • French fries 
  • Cakes, cookies, pastries


Processed meats 

Highly processed meats like bacon, salami, and hot dogs often contain hydrogenated fats and preservatives, which are major gut health disruptors known to trigger symptoms of leaky gut syndrome including bloating, constipation, and gas. 

Artificial sweeteners

Artificial sweeteners and sugar alcohols, including sucralose, saccharin, and xylitol, have been known to negatively alter gut health. They are not recommended for those with existing GI issues as they have a tendency to contribute to leaky gut symptoms.


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