What Is Gut Health? | The Basics of the Gut Environment
“Gut health” refers to lifestyle habits, dietary choices, exercise, and other efforts aimed at supporting a healthy gut environment. More than 100 trillion gut bacteria live in the intestines, where beneficial, harmful, and opportunistic bacteria coexist in balance. When this balance is disrupted, some people may notice changes in how their stomach or skin feels.
An increasing number of studies suggest a connection between the balance of gut bacteria and day-to-day physical condition. Paying attention to the diversity of gut bacteria has become one way people look after their health and appearance. This article focuses on the relationships among three especially popular aspects of gut health: fermented foods, dietary fiber, and beneficial bacteria.
- A term for efforts aimed at supporting a healthy gut environment
- The balance of beneficial, harmful, and opportunistic bacteria is key
- Fermented foods and dietary fiber are two mainstays of gut health
How the Gut Microbiome Works | Beneficial, Harmful, and Opportunistic Bacteria
The many types of bacteria that live in the gut are likened to a flower garden (flora), giving rise to the term “gut flora.” Also known as the gut microbiota, this community can be broadly divided into three types.
| Type of bacteria | Characteristics | Main functions |
|---|---|---|
| Beneficial bacteria | Helpful bacteria | Support digestion and contribute to vitamin synthesis |
| Harmful bacteria | Potentially harmful bacteria | When they become too numerous, they are thought to produce undesirable substances |
| Opportunistic bacteria | Intermediate bacteria | Their activity varies depending on the state of the gut environment |
The goal of supporting gut health is to create an environment in which beneficial bacteria can thrive. “Fermented foods” and “dietary fiber” are essential to this.
Fermented Foods: A Key to Gut Health
There are many types of fermented foods, including yogurt, natto, kimchi, miso, nukazuke (rice-bran pickles), and cheese. They contain probiotics such as lactic acid bacteria and bifidobacteria, which are said to help increase beneficial bacteria in the gut.
| Fermented food | Main bacterial strains | Characteristics |
|---|---|---|
| Yogurt | Lactic acid bacteria and bifidobacteria | Easy to add to your diet |
| Natto | Bacillus subtilis var. natto | Also contains vitamin K and dietary fiber |
| Kimchi | Lactic acid bacteria | Provides vegetables at the same time |
| Miso | Koji mold and lactic acid bacteria | Easy to incorporate into Japanese meals |
When choosing, consider whether the product has no added ingredients and contains live bacteria. Trying different fermented foods to suit your preferences and constitution is another option.
Dietary Fiber and Oligosaccharides for a Healthy Gut
Beneficial gut bacteria are said to feed on dietary fiber and oligosaccharides. There are two types of dietary fiber—soluble and insoluble—and the key is to get a good balance of both.
- Soluble dietary fiber: seaweed, fruit, oatmeal, and more
- Insoluble dietary fiber: vegetables, legumes, whole grains, and more
- Oligosaccharides: bananas, onions, burdock root, asparagus, and more
Combining fermented foods with dietary fiber and oligosaccharides is thought to help create an environment in which beneficial gut bacteria can thrive.
Top Recommended Foods for Gut Health
Here are some foods rich in fermented ingredients or dietary fiber that are often recommended as staples for gut health.
| Rank | Food | Characteristics |
|---|---|---|
| 1st | Yogurt | Rich in lactic acid bacteria |
| 2nd | Natto | Dietary fiber and natto bacteria |
| 3rd | Kimchi | Provides lactic acid bacteria and vegetables |
| 4th | Banana | Oligosaccharides and dietary fiber |
| 5th | Oatmeal | Soluble dietary fiber |
Gradually adding these foods to your daily meals is the foundation of a gut health routine centered on fermented foods, dietary fiber, and beneficial bacteria.