Gut Microflora and Health: How Nutrition Affects Immunity

28.02.2025

Gut Microflora and Health: How Nutrition Affects Immunity
The best foods to support healthy microbiota and prevent diseases

Modern science increasingly points to the key role of gut microflora (or microbiota) in maintaining immunity and overall health. These tiny inhabitants of our gastrointestinal tract are able to influence not only digestion, but also the function of the nervous system, mood, weight, and the risk of developing various diseases. In this article, we’ll discuss how nutrition shapes a healthy microflora, which foods should be included in your diet to strengthen immunity, and what to pay attention to in order to maintain the bacterial balance in your gut.

What is microbiota and why is it important?

Microbiota — is the collection of microorganisms (bacteria, viruses, fungi) that live in our bodies, primarily in the intestines. Scientific studies confirm that the balance of “beneficial” bacteria is necessary for normal functioning of the body:

1. Strengthening immunity. About 70% of immune system cells are located in the gut. Healthy microbiota helps to build resilience to infections and reduces the risk of inflammatory processes.
2. Regulation of digestion. Bacteria participate in breaking down food, synthesizing certain vitamins (K, B group), and maintaining normal peristalsis.
3. Supporting metabolism. An optimal microbial balance ensures more effective absorption of nutrients and prevents excessive weight gain.
4. Influence on the nervous system. The gut is considered the “second brain” since it produces serotonin and other neurotransmitters that affect mood and overall well-being.

How nutrition affects microflora and immunity

Our daily diet is a key factor shaping the species composition of bacteria in the gut. Properly selected nutrition can help “friendly” microbes flourish, while an excess of harmful foods leads to the growth of pathogenic bacteria and suppression of beneficial ones.

• Excess sugar, fast food and processed foods promote the growth of inflammation-causing bacteria and increase gut permeability.
• A balanced diet rich in vegetables, fruits, whole grains and probiotic foods (kefir, yogurt, sauerkraut) helps improve the quality of the microbiota, lowering the risk of inflammation, bloating, and digestive issues.

5 Foods to Support Healthy Microbiota

1. Fermented dairy products

• Kefir, natural yogurt, soured milk, ayran – these products contain probiotics (lacto- and bifidobacteria) that populate the gut with beneficial flora.
• When shopping, pay attention to a short shelf life, low sugar content, and the presence of live bacteria in the composition.

2. Pickled vegetables and fermented foods

• Sauerkraut, kimchi (spicy Korean appetizer), pickled cucumbers (without vinegar), kombucha (tea fungus) – examples of foods rich in probiotics.
• During fermentation, organic acids are formed, which support a healthy microbial community and also improve the absorption of vitamins and minerals.

3. Foods with prebiotic fiber

• Garlic, onion, leek, asparagus, Jerusalem artichoke contain special types of dietary fiber (inulin, oligofructose) that serve as food for beneficial bacteria.
• By including such vegetables in your diet, you stimulate the growth of “good” microbes and strengthen your gut’s protective functions.

4. Whole grains and legumes

• Oatmeal, buckwheat, pearl barley, quinoa, beans, lentils – sources of soluble and insoluble fiber, which normalize the gastrointestinal tract and feed healthy microflora.
• Cooked whole grain products help support long-lasting satiety and stable blood sugar levels, which positively affects the body as a whole.

5. Fruits and berries

• Apples, bananas, berries (blueberries, raspberries, strawberries) and other fruits are rich in fiber, antioxidants, and phytonutrients.
• Polyphenols found in fruits and berries can stimulate the growth of certain beneficial bacteria and protect cells from oxidative stress.

Additional Recommendations

1. Limit refined sugar and simple carbohydrates. Sweets, pastries, and fast food feed pathogenic bacteria, promote inflammation, and reduce immune effectiveness.
2. Avoid frequent use of antibiotics without a doctor’s prescription. Antibiotics destroy not only harmful, but also beneficial bacteria, which can lead to a microflora imbalance.
3. Drink enough water. Optimal hydration is necessary for normal gut function and “transport” of nutrients throughout the body.
4. Reduce stress. The hormone cortisol, which increases during stress, adversely affects the microbiota composition. Relaxation practices, yoga, meditation, and regular physical activity can help reduce stress levels.
5. Monitor your sleep pattern. Lack of sleep weakens the immune system and disrupts the bacterial balance in the gut, increasing the risk of inflammatory diseases.

Conclusion

Healthy gut microflora is the foundation of strong immunity, normal digestion, stable weight, and good mood. Mindful eating, rich in probiotics and prebiotics, can not only strengthen your body but also prevent a number of diseases. Include fermented foods, whole grains, fiber, and fresh fruits in your diet – and after a short while you will notice positive changes in your gut function and overall well-being.

If you are experiencing chronic digestive problems or frequent colds, it makes sense to consult a specialist. A gastroenterologist or nutritionist will select an individual nutrition plan and, if necessary, prescribe additional studies. Remember that healthy microbiota is not a temporary goal, but an important part of your lifestyle, affecting your health for many years to come.