10 Ways to Increase Good Gut Bacteria

Did you know that the majority of your immune system is in your gut?1 Picture a lush, harmonious rainforest teeming with diverse forms of life; this is what a healthy gut should look like at a microbial level. With more than 1,000 microbial species, most of which are bacteria, your gut’s microbiome makes up an essential part of your immune system.2 The good bacteria in your gut protect you from pathogenic invaders and keep harmful bacteria from growing out of control. The good bacteria that live in your gut are an essential part of your body’s microbiome. Here are 10 of the best ways to increase your good gut bacteria.  

1. Eat whole foods

The human body is not meant to run on food-like substances; diet matters! Eating processed foods and refined sugars starves the good bacteria in your gut, allowing harmful bacteria to grow out of control, also known as dysbiosis.3,4 Instead of filling up on processed foods, eat the rainbow. Choosing to eat a wide variety of whole high-fiber foods feeds your good bacteria and, in turn, nourishes your microbiome. Choosing organic produce is also a great way to add good bacteria to your gut's ecosystem.5 By keeping your good bacteria strong and healthy, they can keep you healthy too. 

2. Eat fermented foods

The creation of fermented foods dates back thousands of years, as far as 10,000 BCE, with the advent of yogurt; the health benefits of yogurt are described in Ayurvedic scripts from 6,000 BCE.6 Fermented foods are a great way to support your health by adding good bacteria to your gut’s population of roughly 100 trillion bacteria and microbes. Here are some tasty options for adding fermented foods to your daily diet:

  • Aged cheese
  • Fermented vegetables
  • Kefir
  • Kimchi
  • Kombucha
  • Miso
  • Natto (fermented soybeans)
  • Olives
  • Pickles (fermented)
  • Sauerkraut
  • Tempeh
  • Umeboshi (Japanese fermented plums)
  • Yogurt

3. Take a high-quality probiotic

Probiotics are “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.”7 Choosing a high-quality clinically supported probiotic is a great way to introduce some new friends to your gut. Different strains of probiotics offer different health benefits; here are six things to look for in a probiotic.

4. Feed your good bacteria

Now that you’ve loaded up on good bacteria from probiotic foods, it’s time to feed your new friends! Probiotics and prebiotics go together like, well, probiotics and prebiotics!

Prebiotics are fibers that can resist the digestive process; once prebiotics reach the colon, they are “eaten” (selectively fermented) by specific strains of friendly gut bacteria.8,9 Here are some whole foods filled with prebiotics to feed your microscopic friends:10

  • Apples
  • Apple cider vinegar
  • Asparagus
  • Bananas (with a bit of green)
  • Barley
  • Buttermilk
  • Celery
  • Chicory root
  • Dandelion greens
  • Flaxseeds
  • Garlic
  • Honey (raw)
  • Human milk oligosaccharides (HMOs)
  • Jerusalem artichoke
  • Jicama
  • Leaks
  • Legumes
  • Oats
  • Onions
  • Rye
  • Seaweed
  • Scallions
  • Watermelon
  • Wheat bran

5. Get quality sleep

Research shows a relationship between sleep and diversity within the gut microbiome.11 Consistent, uninterrupted sleep of between seven to nine hours per night has been shown to have a positive correlation to bacterial strains related to good health.12,13

6. Get moving

Consistent exercise results in increased good bacteria. In a six-week study, exercise was shown to increase the numbers of certain strains of good bacteria.14 However, when followed by a six-week sedentary period, the increase of microbiota returned to baseline, so it’s important to get moving and stay moving.14

7. Destress

Stress has been shown to have a negative impact on gut health. Heightened stress levels can trigger an increase in bad/pathogenic bacteria, crowding out good bacteria.15,16 Try these six simple ways to reduce stress.

8. Get some vitamin D

A 2019 study found that skin exposure to UVB light positively impacts the diversity and composition of the human microbiome.17 Vitamin D supplementation also has positive impact on the gut’s microbiome by increasing bacterial diversity and richness.”18,19

9. Take it easy on the cocktails

It’s well known that red wine can support good health, but too much alcohol has been shown to have a negative impact on good gut bacteria.20,21 The CDC 2020-2025 guidelines recommend one drink or less in a day for women and two drinks or less in a day for men.22 The CDC guidelines also caution against beginning drinking for possible health benefits and advise that “drinking less is better for health than drinking more.”22,23 The health benefits of red wine likely stem from polyphenols from the grape skins present in the wine-making process.24-27 Polyphenols are complex compounds found in fruits and vegetables that protect plants from pathogens and UV radiation; these compounds act as an antioxidant and as a prebiotic in the human body.28,29 Plenty of foods are packed with polyphenols, such as:30

  • Apples
  • Blueberries
  • Coffee
  • Cranberries
  • Dark chocolate
  • Dried oregano
  • Dried parsley
  • Flaxseed
  • Kiwis
  • Pecans
  • Tahini
  • Tea

10. Break up with cigarettes

Smoking causes a decrease in microbiome diversity; smoking withdrawal has been found to increase gut microbial diversity.31 Quitting smoking is a great way to show your little critters some love.31

All of these are great ways to help increase the friendly bugs working hard in your gut. Which will you try first?

For more information on gut health and other general health topics, please visit the Metagenics blog.


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