5 Foods to Reduce for a Happy, Healthy Gut

By Melissa Blake, ND

The evidence is overwhelming: diet matters. Much of the benefit of diet is related to the impact on the gastrointestinal system.

A few signs that your digestive system may not be working at its best include:

  • Gas
  • Bloating
  • Discomfort
  • Belching
  • Cramps
  • Changes in bowel movements (more frequent, less frequent, painful, urgent, loose, hard, changes in color, etc.)
  • A bad taste in your mouth
  • Changes in appetite

When it comes to optimal digestion, many foods and supplements support a strong digestive tract, while others do not and may even cause harm. This article is a discussion on the top five foods, or food-like substances, you may want to avoid or reduce for a happy and healthy gut.

“There is no medicine you can take that will replace what you can do for your own health.”―Aarti Patel

1. Refined sugar

Sugar is everywhere, and we are doing a terrible job when it comes to consuming it in moderation. The average American is eating sugar at a rate that far exceeds the daily recommended intake.1

The gut connection:

Helpful bacteria in the gut rely on fiber as an energy source. Whole fruit, for example, provides natural sugars along with fiber, vitamins, and minerals. Refined sugar is just sugar, with all the good stuff removed. Essentially, a diet high in refined sugar provides little to no fiber and changes the food available to the gut microbiome. As a result, the good bacteria starve which leaves an opening for harmful bacteria to flourish.1

Sources of Refined Sugar:High-Fiber Foods:
Beverages: coffee drinks, juice, soda, vitamin or sport drinks

Condiments: BBQ sauce, ketchup, salad dressings

Diet foods: low-fat yogurts, low-fat peanut butter, low-fat sauces

Snacks: cakes, cereals, chocolate bars, cookies, croissants, flavored yogurt, granola, ice cream, jams, jellies, muffins, nut butters, pastries

Other: canned goods, frozen meals  
Unprocessed, whole plant-foods, including:
Chia seeds
Sweet potato      
Also known as: “added sugar”, cane sugar, fruit juice concentrate, high fructose corn syrup, malt syrup, sucrose, table sugar, etc.
Happy tummy tips: Reach for fruit first to satisfy your sweet tooth. When necessary, choose natural sweeteners such as honey and maple syrup, and use in moderation.

2. Artificial sweeteners

Noncaloric artificial sweeteners arrived on the scene partly in an attempt to reduce the trend in weight gain attributed to sugar consumption.2 They unfortunately did not live up to their expectations.

Current evidence suggests these now common food additives contribute to changes in blood sugar that can result in an increase in appetite, a higher intake of calories, and unwanted weight gain.3 Wait! Is that not the opposite of the desired effect?

The gut connection:

Much of this unwanted impact may be the relationship between artificial sweeteners and the microbiome. We are still not clear exactly how these sugar alternatives work against the gut bacteria. It might be that they harm the helpful bacteria or directly promote the growth of harmful ones.4

Either way, the results are not exactly the sweet story we were hoping for.

Artificial sweeteners are also known as: nonnutritive sweeteners, noncaloric sweeteners, and sugar substitutes.  
Happy tummy tips: Read labels. Artificially sweetened products may be labeled as “sugar-free.” Consider monk fruit or allulose as alternatives.

3. Alcohol

Alcohol affects human health by influencing the function of many organs and systems, but perhaps most importantly the gastrointestinal system.5

The gut connection:

Specifically, chronic alcohol intake disrupts the microbial balance, contributing to a remarkable shift in the gut community and an increase in intestinal permeability.5,6

The resulting dysbiosis (imbalance in your digestive bacteria) has a negative impact on the production of important metabolites, including short-chain fatty acids and precursors to neurotransmitters and hormones.7   

In addition to the impact on the gut and associated dysbiosis, acute alcohol consumption promotes unsafe behaviors, is a stress on the liver, contributes to sleep disturbances, and is a source of sugar and empty calories.8 Not exactly news worth making a toast to.

Happy tummy tips: Drink within the recommended guidelines outlined by the National Institutes of Health (up to 1 drink per day for women and up to 2 drinks per day for men).9 Never drink on an empty stomach. Tune in and pay attention to how your digestive system feels before, during, and after drinking alcohol. Is it worth it?

4. Conventionally raised animal products

Animal products can provide a wide variety of important nutrients, including amino acids, B12, and iron. Problems can arise when a high intake of animal products leads to a lower intake of vegetables and other plant foods.

The gut connection:

Long-term adherence to high-protein diets, especially in the absence of plant fiber, contributes to an imbalance in gut bacteria.10,11 It makes sense, then, that a higher intake of meat, red and processed meats in particular, contributes to lower levels of protective metabolites and an increase in harmful metabolites produced by gut bacteria.12

It is not just quantity, but also quality that matters.

Conventional farming and the associated exposure to pesticides has implications for both the farmers and the environment,while organic farming promotes better animal welfare and a slightly better nutritional profile.13,14

A major concern related to conventionally raised animals is the extensive use of antibiotics that is contributing to resistant strains of harmful bacteria.15 Although research has not yet extensively studied the specific implications of prophylactic antibiotic use in animals to the gastrointestinal tract in humans, we can only assume this global health and environmental issue is also a gut one.15

Happy tummy tips: Choose local, organic, or ethically raised meat and animal products whenever possible. Focus on the ideal plate that includes 50% vegetables, 25% whole grains/starchy vegetables, and 25% protein. Opt for vegetarian options more often.

5. Conventionally grown coffee

Now, let us talk coffee.

Conventionally grown coffee is one of the most heavily chemically treated foods in the world. Think synthetic fertilizers, pesticides, herbicides, fungicides, and insecticides that have short and long-term implications for farmers and local environments.16 Reason number one to choose an organic, fair-trade option.

Here are a few more reasons to keep coffee intake to a moderate level and always choose a quality option.

The gut connection:

Drinking coffee causes an increase in stomach acid. This might be okay for the average Joe, but too much acid can irritate the stomach lining and contribute to sensation of burning and digestive distress. This irritation does not stop at the stomach but can move along the entire digestive tract, contributing to its laxative effect and promoting cramps, spasms, and diarrhea.17

When it becomes a habit, coffee can contribute to dependency and symptoms of withdrawal when trying to reduce intake. Coffee is also a diuretic and can contribute to dehydration, especially as consumption increases and it starts to replace water intake.18

In moderation, coffee can be a delightful morning ritual, but if you already suffer from stomach or digestive complaints, coffee is likely to make things worse.

Happy tummy tips: Choose organic, fair-trade coffee and drink in moderation. Consider switching that second cup of coffee for a cup of herbal tea or sparkling water. If you already suffer from digestive complaints, consider drinking coffee on a full stomach or avoiding it altogether.  


Food choices play a huge role in gut health. Certain foods can wreak havoc on the digestive system by contributing to an imbalance in the microbiome, irritating the gut lining, and influencing the amount of digestive enzymes present.

An optimal diet goes beyond looking at food as simply a source of calories. Diet composition and quality are important factors to consider when it comes to optimizing function and promoting health.

Three takeaways to help improve your digestive health:

  • Choose local, organic options when possible, especially animal products and coffee.
  • Eat more vegetables. Aim for the ideal plate that includes 50% vegetables, 25% whole grains/starchy vegetables, and 25% protein as often as possible.
  • Keep track of how you feel physically, emotionally, and mentally when you eat/drink certain foods or food-like substances. This knowledge will empower you to make decisions that best reflect your health and wellness goals.


  1. Di Rienzi SC et al. Adv Nutr. 2020;11(3):616-629.
  2. Mooradian AD et al. Clin Nutr ESPEN. 2017;18:1-8.
  3. Pearlman M et al. Curr Gastroenterol Rep. 2017;19(12):64.
  4. Bokulich NA et al. Cell Metab. 2014;20(5):701-703.
  5. Dubinkina VB et al. Microbiome. 2017;5(1):141.
  6. Bishehsari F et al. Alcohol Res. 2017;38(2):163-171.
  7. Qamar N et al. Behav Brain Res. 2019;376:112196.
  8. Delker E et al. Alcohol Res. 2016;38(1):7-15.
  9. U.S. Department of Health and Human Services and U.S. Department of Agriculture. 2015–2020 Dietary Guidelines for Americans. 8th Edition. December 2015. Available at http://health.gov/dietaryguidelines/2015/guidelines/.
  10. Russell WR et al. Am J Clin Nutr. 2011;93(5):1062-1072.
  11. Singh RK et al. J Transl Med. 2017;15(1):73.
  12. Zeneng W et al. Eur Heart J. 2019;40(7):583-594.
  13. Nankongnab N et al. J Agromedicine. 2020;25(2):158-165.
  14. Mie A et al. Environ Health. 2017;16(1):111.
  15. Seal BS et al. Anim Health Res Rev. 2013;14(1):78-87.
  16. Hutter HP et al. Int J Environ Res Public Health. 2018;15(8):1641.
  17. Boekema PJ et al. Scand J Gastroenterol Suppl. 1999;230:35-39.
  18. Seal AD et al. Front Nutr. 2017;4:40.
Melissa Blake, ND
Melissa Blake, ND is the Manager of Curriculum Development at Metagenics. Dr. Blake completed her pre-medical studies at Dalhousie University in Halifax, Nova Scotia, and obtained her naturopathic medical training from the Canadian College of Naturopathic Medicine. Dr. Blake has over 10 years of clinical experience, specializing in the integrative and functional management of chronic health issues.

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