Research-Based

Worst Foods For Gut Health – Foods You Should Stop Eating Now

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By Thomas Youngerman

Reviewed by Juliana Tamayo, MS, RDN - Last Updated

Worst Foods For Gut Health

Americans are becoming enamored with gut health. From maintaining digestive health to the gut-brain axis, the microbiome, pre-and probiotics, gut buddies, and leaky gut, it’s all in the news. Dr. Steven Gundry, founder of Gundry MD and the author of the Plant Paradox and Dr. Gundry’s Diet Evolution, is quoted in clinical studies and business articles; he is featured in podcast productions and YouTube videos. Although Dr. Gundry is prodigious in his works on gut health, he is far from the first to state its importance. Nearly 2500 years ago, Hippocrates said that “all disease begins in the gut.” 

If Dr. Gundry and Hippocrates are right, perhaps the following numbers explain the current obsession with gut health. 

Although the numbers and percentages differ according to the resource, it’s apparent that gastrointestinal symptoms in adults in the U.S. have reached overwhelming proportions. Most studies indicate that 60 – 70 million Americans suffer from one of the following:

  • Heartburn/Reflux
  • Abdominal Pain
  • Bloating
  • Diarrhea
  • Constipation
  • Nausea/Vomiting
  • Incontinence

The NCBI (National Center for Biotechnology Information), in an exhaustive study approved by the Cedars-Sinai Institutional Review Board, found that 61% of participants, over 71,000 people suffered from some form of these symptoms.  

If you are what you eat is true and knowing that the food you consume delivers the nutrients you need throughout your body, understanding what you should and should not include in your diet seems a worthy topic. 

This article pays homage to Dr. Gundry’s theories. It then goes beyond his “holobiotics” to include contrary opinions on which foods are healthy and which should be avoided as potential triggers to gastrointestinal symptoms. So, what are the worst foods for gut health? We’ll give you a thorough look at the answer to that question as well as more information surrounding gut health.

Healthy Gut

As a prelude to the “worst foods for gut health,” let’s first discuss some healthy protocols and lifestyle choices that improve your potential for good gut health!

Basic Protocols for a Healthy Gut

The digestive symptoms listed in the NCBI study above are not life-threatening typically, but they can have a negative effect on the quality of life. A working definition of a healthy gut might be “an absence of gastrointestinal issues, leading to a state of physical and mental well-being.” We include physical and mental as gut health impacts whole-body health, including digestion, the immune system, heart and brain health, and more.

probiotic foods

Tips for Maintaining a Healthy Gut

  • Consume more pre-and probiotic foods or supplements – especially important if you have taken antibiotics. 
  • Eat a diverse variety of whole foods, such as fruits, vegetables, and whole grains.
  • Move, regular exercise is essential in any health regimen.
  • Avoid all tobacco products.
  • Alcohol consumption only in moderation.
  • Get enough sleep.
  • Avoid stress as much as possible – consider stress management techniques such as mindfulness, meditation, or yoga

We understand the above may be predictable and overused, but the best advice is often ignored, searching for the secret sauce. Incorporate the above into your daily regimen, and you will see results. 

Dr. Gundry’s “Holobiotics” – Foods He Says To Avoid

Dr. Steven Gundry coined or popularized terms such as “Holobiotics,” “gut buddies,” lectins, and nightshade vegetables. His primary tenant is to take care of your good microbes, limit the bad ones by your food choices, and balance your microbiome to live in a state of microbe cooperation. Gundry MD is a nutritional supplement company known for its pre-and probiotic products, such as Bio Complete 3, 24 Strain Probiotic, and Primal Plants. Gundry MD supplements are designed to support the good microbes – your “gut buddies.” 

Dr. Gundry’s “Holobiotics”

To limit harmful microbes, Dr. Gundry preaches the avoidance of certain foods due to their high lectin content. Lectins are a type of plant protein found in almost all foods, thought to be a part of a plant’s self-defense system. The human body cannot digest lectins, contributing to digestive issues when consumed in large quantities, such as poor nutrient absorption, damage to the gut wall, and leaky gut syndrome. 

The foods that are believed to be highest in lectins and which should be avoided per Dr. Gundry include: 

  • Beans and legumes
  • Whole grains
  • Nightshade vegetables (tomatoes, peppers, eggplant, and potatoes) 
  • Certain nuts and seeds (peanuts, cashews, sunflower seeds)
  • Dairy products
  • Grain-fed animal proteins

Strategies to reduce the lectin content in the above foods include:

  1. Soak dried beans (at least 4 hours) and pour off the water before cooking – or pressure cook. 
  2. Nightshades should be peeled and deseeded before use.
  3. Fermenting or sprouting.

Other foods Dr. Gundry recommends you eliminate or severely restrict include refined and starchy foods, sugar-laden fruits, foods sweetened with fructose, such as soda, candy, and fruit juices, and artificial sweeteners. 

Unfortunately, the highest concentrations of lectins are sometimes found in healthy foods – legumes, grains, and nightshade vegetables. Other nutritionists and researchers find lectins less onerous and believe eliminating all foods with lectins would mean missing out on essential nutrients. For example, proponents of the Mediterranean Diet, which happens to be the most studied diet for heart health and other inflammatory conditions, incorporate whole grains, legumes, and nightshade vegetables in their diet for their various health benefits. A diet that includes a wide variety of whole foods can lead to more diverse gut flora.

Other Worst Foods for Gut Health

Certain foods cause inflammation in the body, along with free radical damage, inflammation is one of the two most dangerous precursors to serious health conditions. Packaged and processed foods with added sugars, refined carbohydrates, and excess sodium should be avoided. 

Fried foods are generally high in saturated fats, and the heated oil, which soaks into fried foods, can damage healthy gut bacteria. We recommend roasted or baked as a preferred and healthier alternative. 

Processed foods

Cruciferous vegetables (cabbage and broccoli) have the same sugars that make beans gassy. Combined with their high fiber content, this can make these vegetables hard to digest for some people. We suggest you always cook these vegetables versus eating them raw.

Red meat contains L-carnitine, which can trigger a change in the composition of gut microbiota. If you love red meat, we recommend moderation and grass-fed beef.  

To develop good gut health, an efficient digestive system with excellent nutrient absorption, a lack of gastrointestinal conditions, and a favorable balance of gut microbiota, other items to be avoided include:

  • Antibiotics (if possible) can alter the type and the number of bacteria in the gut.
  • NSAIDs (Nonsteroidal Anti-Inflammatory Drugs), known to damage the gut’s lining resulting in leaky gut syndrome.

In Summary: Foods for Gut Health

We believe that practicing good gut health equates favorably with taking care of your overall health and wellbeing. From your skin to heart health, acknowledging and tending to the gut-brain axis, and supporting your immune system, a healthy gut with a balanced microbiome is essential.

Good gut health

The health of almost everything in your body, including mental health and mood, is dependent on making healthy choices for your digestive system – what to eat to support beneficial microbes and what foods to avoid. We hope this article has helped to shed some light on both the positive protocols and worst foods for gut health.

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Thomas Youngerman

Thomas Youngerman is an entrepreneur and author in the health and wellness space with extensive experience in the supplement industry. He has owned multiple sports nutrition stores and served as the Category Manager and Director of Business Development for a regional chain of nutrition stores. Thomas created a successful line of men’s healthy aging supplements that was distributed in GNC, The Vitamin Shoppe, and Kroger, and later sold to a West Coast corporation. Thomas was previously a certified nutrition coach. He has a strong understanding of nutrition, supplement formulations, DSHEA, cGMP, and FDA regulations.