The digestive tract is 10 meters long, with the intestine accounting for 6-9 meters and weighing 2 kilograms. It is precisely in the intestine that good bacteria, essential for the body's health, settle.
Probiotics are beneficial bacteria, usually lactobacilli and bifidobacteria, that maintain the balance of the intestinal microflora. 80% of immune cells are found in the gut, so probiotics directly affect immunity. Lactobacillus rhamnosus bacteria have been studied in over 260 clinical trials, confirming their positive effect on immunity and digestion.
Probiotics in 2025 – new knowledge about bacterial species, mechanisms of action, and benefits for different groups of people. A capsule of ProViotics food supplement contains 25 billion live bacteria and 10 different bacterial cultures.
Probiotics – live microorganisms beneficial to health
According to the World Health Organization, probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. These beneficial bacteria ensure vital functions in the body.
Definition of Probiotics
Probiotics are live microorganisms, usually bacteria and yeasts, naturally found in some food products and supplements. Most commonly used are Lactobacillus and Bifidobacterium species, as well as Saccharomyces cerevisiae yeast and some E. coli and Bacillus species.
A microorganism is considered a probiotic if it meets three criteria:
- resistant to stomach acids and bile salts
- capable of adhering to the intestinal lining
- safe for human health
In the adult human body, microorganisms constitute about 3-4 kilograms of weight; their quantity is 10 times greater than that of human cells. Each person has a unique set of microorganisms, similar to fingerprints.
Effect of Probiotics on Gut Microflora
Probiotics work directly – they enter the intestines and maintain the balance of the microbiota. They control the growth of pathogenic bacteria and prevent them from settling in the intestines.
Probiotics also:
- Produce substances that destroy pathogenic microorganisms
- Compete with bad bacteria for nutrients
- Physically compete for space on the intestinal walls
- Stimulate the immune system
Probiotic bacteria produce vitamin K and short-chain fatty acids. These acids nourish the cells of the intestinal lining and strengthen the intestinal barrier.
Lactic acid, produced by probiotics, improves the absorption of calcium, magnesium, and copper. A low pH in the intestines is essential for minerals to enter the bloodstream.
Probiotics and Prebiotics – Differences
Prebiotics are food for probiotics, not bacteria. They are indigestible carbohydrates that reach the large intestine unchanged. They become a substrate for probiotics and stimulate their growth.
Prebiotics are typically soluble fibers that the human body does not digest. Beneficial gut microbes ferment these substances and derive energy.
The main groups of prebiotics are galactooligosaccharides (GOS) and inulin-type fructans. Fructooligosaccharides, inulin, pectin, and lactose are also considered prebiotics.
Good bacteria naturally reside in the body, but their balance can be disrupted by poor nutrition, chronic diseases, or antibiotics. Consuming probiotics and prebiotics helps restore this balance.
Studies show that probiotics reduce the need for antibiotics, the likelihood of colds, the risk of pneumonia, and symptoms of gestational diabetes and eczema. Different probiotic strains have different effects, so not all probiotics are equally effective.
Lactobacilli – Key Strains and Health Benefits
Lactobacilli are the largest group of probiotic bacteria in the gut. They produce lactic acid, which creates an unfavorable environment for pathogens. There are over 50 different species of lactobacilli.
Lactobacillus acidophilus
Lactobacillus acidophilus is one of the most important strains. It naturally lives in the digestive tract, mouth, and vagina. It is found in fermented products, especially yogurt.
The main property of L. acidophilus is that it lowers the pH of the environment, inhibiting the growth of pathogenic bacteria. It is effective in treating acute and chronic diarrhea, as well as post-antibiotic diarrhea. It can absorb cholesterol.
L. acidophilus strengthens the immune system and maintains the health of the vaginal microflora in women. It is resistant to low pH and survives in the duodenum in the presence of bile acids.
Lactobacillus rhamnosus
L. rhamnosus is the most researched lactobacilli strain globally. Its positive effects have been proven in over 260 clinical trials. It is found in the gut, mouth, and vagina.
L. rhamnosus strengthens the immune system, helps prevent respiratory diseases and tooth decay. It fortifies the barrier of the digestive tract lining and acts against pathogenic bacteria.
It reduces the risk of allergies and helps to more quickly alleviate the consequences of atopic dermatitis. It is able to survive after passing through the digestive tract.
Lactobacillus plantarum
L. plantarum is found in dairy products, vegetables, meat, and wine. It naturally lives in the digestive tract, vagina, and urinary tract. It secretes antimicrobial substances.
L. plantarum:
- Produces hydrogen peroxide – protection against foodborne bacteria
- Supports immune function in healthy adults
- Treats irritable bowel syndrome, colitis, Crohn's disease
- Helps prevent soy-induced allergies
Lactobacillus gasseri
L. gasseri is a promising probiotic bacterium. It produces lactic acid, which protects the stomach and intestinal lining.
L. gasseri is distinguished by its effect on weight control. A study showed that L. gasseri SBT2055 reduces abdominal fat, which is associated with the risk of diabetes, heart disease, and cancer.
Women experiencing vaginal discomfort typically have fewer L. gasseri bacteria in their bodies than healthy women.
Lactobacillus salivarius
L. salivarius is a unique bacterium capable of growing in adverse conditions, even in environments with high salt concentrations or without oxygen. It is most commonly found in saliva.
It improves digestion, strengthens immunity, and enhances dental health. It produces bacteriocin – an antimicrobial substance against pathogens.
It inhibits the growth of H. pylori bacteria (which cause stomach ulcers). It inhibits the formation of biofilms by other bacteria and fungi (Candida albicans).
L. salivarius grows very rapidly, so it quickly acts against bad bacteria. A six-week course of L. salivarius with fructooligosaccharide reduces total cholesterol, "bad" (LDL) cholesterol, triglycerides, and increases "good" (HDL) cholesterol.
Bifidobacteria – a major part of beneficial gut bacteria
Bifidobacteria colonize the digestive tract immediately after birth. These Gram-positive, rod-shaped bacteria are essential for gut health and immune system strengthening. Billions of bifidobacteria, residing on the walls of the large intestine, protect against the spread of harmful bacteria.
Bifidobacterium bifidum – an important part of the large intestine microflora
B. bifidum is widely prevalent in the intestines of newborns. It adheres to the intestinal mucosa better than pathogenic bacteria, blocking the growth of bad bacteria, fungi, and yeasts.
This strain aids in the digestion of complex carbohydrates, fats, and proteins. Studies have shown its effective impact in reducing traveler's diarrhea. Together with Lactobacillus acidophilus, it helps prevent eczema in newborns.
Bifidobacterium longum – colonizes the intestine throughout life
B. longum is one of the simplest bifidobacteria in the human digestive tract. It is characterized by its ability to break down carbohydrates and neutralize intestinal toxins.
Studies have confirmed its antioxidant properties – it removes metal minerals and free radicals. Immune parameters in elderly patients significantly improved 20 weeks after B. longum consumption.
Bifidobacterium infantis – the foundation of newborn microflora
The densest colony of B. infantis is found in newborns and young children. The number of bacteria decreases with age, but remains important for the microflora.
It helps alleviate symptoms of irritable bowel syndrome – abdominal pain, gas accumulation, bloating. It accelerates the maturation of the immune response, reduces inflammation, and improves intestinal barrier function.
Bifidobacterium breve – assimilates complex food components
B. breve is unique in its ability to assimilate food components that other bacteria cannot process. It is most commonly found in the intestines of healthy infants and in breast milk.
For premature babies and those born via C-section, B. breve provides a microflora characteristic of naturally fed infants. It reduces chronic periodontitis, the occurrence of oral wounds, urinary oxalate levels, and Helicobacter pylori colonization.
Bifidobacterium adolescentis – prevalent in adult organisms
B. adolescentis is one of the most abundant Bifidobacterium species in the adult digestive tract. It synthesizes B vitamins – B1, B2, B6, B12 and folic acid.
It exhibits anti-inflammatory, antioxidant, and antiviral properties. It strengthens the intestinal barrier, protecting against pathogens and toxins. It participates in GABA production – a neurotransmitter that reduces stress.
Studies show a significant effect of B. adolescentis in delaying aging – it increases superoxide dismutase activity in the blood, reduces free radical damage, and prolongs lifespan.
Streptococcus thermophilus – a beneficial probiotic for those intolerant to milk
Streptococcus thermophilus is one of the first identified probiotic bacteria, used in the production of yogurt and cheese. The bacteria grow at temperatures of 35-42°C.
S. thermophilus breaks down lactose into lactic acid – helping people with lactose intolerance. Studies confirm that these bacteria protect against intestinal irritation, reduce antibiotic-induced diarrhea, and prevent chronic gastritis.
The bacteria produce antibiotic substances that help prevent intestinal ulcers. In experiments with C. difficile-infected animals, a 40% lower weight loss was observed.
S. thermophilus is most effective when combined with Lactobacillus strains.
Probiotic complexes – more effective action
Combined probiotic complexes are combinations of several bacterial strains for maximum effect. S. thermophilus stimulates the growth of other probiotics, which is why it is often used as a starter culture for yogurt.
Complexes combine various strains: Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus reuteri, Bifidobacterium lactis, and Lactobacillus plantarum.
After antibiotic use, Lactobacillus reuteri is particularly beneficial – it restores the intestinal microflora. Bifidobacterium lactis normalizes bowel movements, while Lactobacillus plantarum reduces abdominal bloating.
Studies confirm that the strains complement each other and create a synergistic effect. Complexes more effectively address digestive problems and strengthen immunity.
Probiotic Use – Timing and Storage Conditions are Important
It is recommended to take probiotics with meals or in the evening. During the night, intestinal activity is less active – good bacteria have more opportunities to integrate effectively.
When used with antibiotics – a 1-hour break is necessary. Start the probiotic course from the first day of antibiotic use and continue for 20 days after the antibiotic course.
Optimal use:
- With food or 30 minutes before a meal
- Avoid taking immediately after a meal
- Dissolve powders in room temperature water
- Do not consume with hot beverages
Usual dose: adults – one capsule per day, children – half, infants – one-third. Standard course – 20 days.
Store most probiotics in the refrigerator (+2-8°C), in a dry place, in their original packaging. Avoid temperatures above 25°C, sunlight, and oxygen. Probiotics must not be frozen.
When starting probiotics, side effects may occur: digestive discomfort, gas accumulation, bloating. Symptoms usually disappear within two weeks.
How to reduce side effects:
- Start with a lower dose
- Drink more water
- Allow the body to adjust
Use with caution in individuals with weakened immune systems or chronic diseases. Consult a doctor before starting use.
Probiotics for different groups – children, women, travelers
Different groups of people require different probiotics. Probiotics intended for children are ineffective for adults, and those for adults are ineffective for children.
Probiotics for children
In the first years of life, probiotics form protective reactions in young children's bodies. Children's gut microflora is sensitive and can be disrupted by infectious diseases, dietary changes, stress, or antibiotics.
Good bacteria for children:
- Breaks down nutrients after digestion
- Produces B vitamins
- Helps produce digestive enzymes
- Reduces the risk of rotavirus
Studies confirm that probiotics shorten the duration of diarrhea by one day. Especially beneficial after a course of antibiotics, taken 4 hours after the last dose of medication.
For children, Lactobacillus rhamnosus GG and Bifidobacterium lactis strains are recommended – they strengthen the mucous membrane barrier and reduce the risk of allergies.
Probiotics for women
For women, probiotics are important for maintaining vaginal microflora. Lactobacillus rhamnosus and Lactobacillus gasseri are most valuable for women's health. Women experiencing vaginal discomfort have fewer L. gasseri bacteria than healthy women.
Probiotics reduce the impact of reproductive health risk factors, strengthen immunity, regulate hormone balance, and reduce inflammation.
Probiotics for travel
For travelers, probiotics are an important helper, especially in countries with a higher risk of intestinal infections. Traveler's diarrhea is resolved by proper probiotic use.
Saccharomyces boulardii yeast restores damaged mucosal biofilm, protecting against damage. Start taking probiotics 2-3 days before travel and continue throughout your stay abroad.
Choose probiotics according to individual needs, age, and health problems. Consult a doctor or pharmacist for the most suitable choice.
Health benefits of probiotics – scientifically proven facts
Good bacteria improve digestion, strengthen immunity, reduce inflammation in the body, help absorb nutrients, and positively affect mood.
Lactobacteria, bifidobacteria, and Streptococcus thermophilus work synergistically – ensuring the balance of intestinal microflora. Combined probiotic complexes provide the greatest benefits.
Probiotic use should be individualized. Children, women, and travelers need different probiotic strains. Before starting to take probiotics, it is essential to consult a specialist.
Many probiotics are recommended to be stored in the refrigerator, taken with food or before bed. When taking antibiotics – maintain an hour gap between medications.
Probiotics are just one of the measures that help maintain good health. Balanced nutrition, fermented products, fiber, prebiotics, physical activity, and rest – all these factors form a healthy gut microbiome.
FAQ
Q1. What are probiotics and why are they important? Probiotics are beneficial bacteria that maintain the balance of intestinal microflora and strengthen immunity. They improve digestion, reduce inflammation, and positively affect mood.
Q2. What are the main probiotic strains? The main strains are lactobacilli (Lactobacillus acidophilus, L. rhamnosus) and bifidobacteria (Bifidobacterium bifidum, B. longum). Streptococcus thermophilus is also important.
Q3. How to take probiotics correctly? Take with meals or before bed. When taking antibiotics – maintain an hour gap between antibiotics and probiotics. Many probiotics should be stored in the refrigerator.
Q4. Do probiotics have side effects? When starting to take probiotics, temporary digestive discomfort, gas accumulation, or diarrhea may occur. Symptoms usually disappear within two weeks. If you have health problems, consult a doctor.
Q5. Are the same probiotics suitable for everyone? Different probiotic strains are needed for different groups (children, women, travelers). Probiotics are chosen according to individual needs, age, and specific health problems.
FAQ
Q1. What are probiotics and why are they important? Probiotics are beneficial bacteria that help maintain the balance of the intestinal microflora and strengthen immunity. They help improve digestion, reduce inflammation, and can even positively affect mood.
Q2. What are the main probiotic strains? The main probiotic strains are lactobacilli (e.g., Lactobacillus acidophilus, L. rhamnosus) and bifidobacteria (e.g., Bifidobacterium bifidum, B. longum). Streptococcus thermophilus is also important.
Q3. How to take probiotics correctly? Probiotics are best taken with meals or before bed. If you are taking antibiotics, leave at least an hour between taking antibiotics and probiotics. Many probiotics should be stored in the refrigerator.
Q4. Do probiotics have side effects? When you start taking probiotics, you may experience temporary digestive discomfort, gas, or diarrhea. These symptoms usually disappear within two weeks. If you have health problems, consult your doctor before taking them.
Q5. Are the same probiotics suitable for everyone? No, different groups (e.g., children, women, travelers) may need different probiotic strains. Probiotics should be selected based on individual needs, age, and specific health problems.
