There are roughly 39 trillion bacteria on and in your body, most of which are found in your gut, also referred to as the digestive system or GI tract. These bacteria are known as the gut flora, gut microbiome, or gut microbiota. Many factors, including the foods you eat, can affect the type of bacteria found in your digestive tract.
“Gut health” is a term used to describe the function and balance of bacteria in the gastrointestinal (GI) tract. There are many reasons you should care about gut health in addition to supporting healthy digestion. Gut health plays an important role in immunity. Studies have also shown that it may have an effect on mood, cognition, and overall health.
Probiotics and prebiotics can help create and maintain a balanced gut flora to support many aspects of your health and well-being.
Probiotics

Usually when people think of bacteria, they think of something they don’t want or something that can cause sickness. There are two kinds of bacteria that can live in your body – “bad” bacteria that can cause illness and infection, and “good” bacteria that ward off bad bacteria and maintain balance in your body.
When you get sick, bad bacteria invade your body. This disrupts the balance of the good bacteria that live in your body. When you take antibiotics, they often kill the good bacteria in your body along with the ones that caused the infection.
The foods you eat most often can also affect your gut flora. A low-fiber diet that is high in refined sugars, red meat, and saturated fat can cause the gut flora to be unbalanced.
Eating probiotic-containing foods or taking a probiotic supplement can help repair this imbalance.
Most foods that involve fermentation during production have probiotics. You may already be eating foods that contain probiotics without even knowing it.
Here are some probiotic-rich foods you can include in your diet:
- Sourdough bread
- Yogurt
- Buttermilk
- Cottage cheese
- Kombucha
- Tempeh
- Fermented pickles
- Fermented sauerkraut
- Kimchi
- Miso soup
If you find that you aren’t getting many of these foods in your diet, or maybe you don’t like these foods, taking a gut health supplement like Naked Gut from Naked Nutrition is always an option to promote ideal gut health.

Prebiotics
Prebiotics are a kind of dietary fiber that feed the healthy bacteria (probiotics) living in the gut. They are found in some carbohydrates, mostly fiber, that the body cannot digest. Prebiotics work like fertilizer to stimulate the growth of healthy gut bacteria. These bacteria use these prebiotics (foods with indigestible fiber) as fuel for fermentation.
Prebiotics make it possible for gut bacteria to produce important nutrients for colon cells. These nutrients can lead to a healthier digestive system, improved metabolic health, and stronger immunity.
Some of the nutrients produced by gut bacteria include short-chain fatty acids. These fatty acids can then be absorbed into the bloodstream and aid in improving metabolic health.
Studies have identified several processes that are facilitated by these fatty acids. These processes affect the regulation of metabolism, inflammation, and play a role in preventing disease.
Foods with Prebiotics

While most fiber-containing foods function as prebiotics, studies suggest that the following foods contain have a significant prebiotic effect on gut health:
Garlic
Garlic acts as a prebiotic by facilitating the growth of Bifidobacteria in the gut. It has been shown to prevent harmful bacteria from growth in the digestive system. Garlic also has antioxidant, anti-inflammatory, and lipid-lowering capabilities.
Onions
Onions are high in inulin and fructooligosaccharides (FOS). FOS are short fructose chains that enhance the gut flora, help with fat metabolism, and support the immune system. Inulin is a soluble fiber, which feeds the good bacteria in the gut, such as Bifidobacteria and Lactobacillus.
Leeks
Leeks contain inulin which gives them prebiotic properties. Leeks support healthy gut flora and aid in fat metabolism.
Asparagus
Asparagus contains both prebiotics and antioxidants. Asparagus contains inulin which can support digestive health and regulate blood sugar.
Bananas
Bananas are high in fiber, which is an important fuel source for healthy gut bacteria. Bananas also contain inulin and vitamins and minerals that are essential to health.
Barley and Oats
Barley and oats contain high levels of beta-glucan, a prebiotic fiber that promotes the growth of beneficial bacteria in the gastrointestinal tract.
Apples
Apples are high in fiber, particularly pectin, which has prebiotic benefits. A study performed in rats found that the pectin in apples could promote beneficial gut bacteria, decrease inflammation, and help with weight management.
Pectin increases the amount of short-chain fatty acids that supply food for healthy gut bacteria and discourages harmful bacteria from colonizing in the digestive system.
Cocoa
Cocoa is a source of antioxidants, particularly flavonols. Flavonols have been shown to increase the amount of healthy gut bacteria and inhibit unhealthy bacteria growth.
Flax seed
Flax seeds are pretty commonly known for their health benefits due to their antioxidant and anti-inflammatory properties. Additionally, they function as a prebiotic. Flax seeds contain fiber which serve as fuel for healthy bacteria. This promotes a balanced microflora and prevents the growth of harmful bacteria.
Flax seeds also promote regular bowel movements and possibly reduce the amount of dietary fat that is digested and absorbed.
Consequences of an Unbalanced Gut Flora

Many aspects of modern life, including increased stress levels, inadequate sleep, consuming too many refined and high-sugar foods, and taking antibiotics, can damage your gut flora.
Unbalanced gut flora can negatively impact several aspects of your health, including the brain, heart, immune system, skin, weight, hormone levels, ability to absorb nutrients, and even the development of cancer.
A healthy balance of good bacteria can improve digestive health, immunity, and reduce inflammation. A healthy gut flora can also:
- Aid in digestion
- Synthesize vitamins
- Aid in metabolism and absorption of medications
- Maintain or restore intestinal mucosa (intestinal cells) integrity to prevent bad bacteria from entering the blood
Scientists continue to study probiotics and their effect on disease outcomes. There are many possible benefits of probiotics, but researchers continue searching for more conclusive answers.
So far, probiotics have shown a potential to affect the outcomes of the following conditions positively:
- Irritable bowel syndrome (IBS)
- Diarrhea
- Constipation
- Yeast infections
- Gum disease
- Eczema
- Lactose intolerance
Summary
Your gut flora is made up of trillions of microorganisms including bacteria, fungi, and other microbes.
The balance of your gut flora plays a vital role in your overall health and well-being, not just in digestion.
An imbalance of unhealthy and healthy bacteria in the intestines may contribute to weight gain, high blood sugar, high cholesterol and other disorders. To support a balanced gut flora, eat a wide variety of fruits, vegetables, whole grains and fermented foods. You can also take a supplement to support gut health.