- How do antibiotics affect the microbiome?
- Other effects of antibiotics
- How to care for the microbiomeduring antibiotic therapy - probiotics
- How to take care of the microbiome during antibiotic therapy - prebiotics in the diet
- Sources of prebiotics in the diet
- Fermented foods and the microbiome
- What diet with antibiotics?
- How to take care of the gut microbiota - lifestyle
VERIFIED CONTENTAuthor: Aleksandra Żyłowska-Mharrab, dietitian, food technologist, educator
Antibiotics, effectively destroying pathogenic bacteria, also destroy the good bacteria of the human microbiome. More and more studies show that antibiotics can cause microbial dysbiosis, and that disturbances in the gut microbiota in newborns, children and adults contribute to many diseases. Therefore, when taking antibiotics, remember not only to take protective drugs (probiotics). How else can you take care of the microbiome during antibiotic therapy?
The role of antibiotics is to kill or prevent bacteria from multiplying. Some antibiotics have a broad spectrum of activity, others are only effective against certain species of bacteria. However, their action is not limited to pathogenic bacteria. Apart from the "bad" bacteria, they also kill the "good" ones.
This may result indisturbance of the gut microbiota , which can contribute to many diseases, including:
- diabetes,
- obesity,
- inflammatory bowel disease,
- asthma,
- rheumatoid arthritis,
- depressed,
- autism
- of superinfections in critically ill patients.
Effective elements to support good intestinal bacteria during antibiotic therapy are:
- probiotic supplementation,
- diet rich in prebiotics,
- eating yoghurt,
- avoiding sugar,
- good sleep,
- not smoking.
How do antibiotics affect the microbiome?
Antibiotics affect the microbiome directly and indirectly. Indirect action is the massive killing of intestinal commensal bacteria and inhibition of their multiplication. However, not all antibiotics work the same way. For example:
- vancomycin reduces stool microbial diversity and the absolute number of gram-positive bacteria, especially Firmicutes,
- amoxicillin does not significantly alter total bacterial count and microbial diversity,
- The combination of antibiotics containing ampicillin, gentamicin, metronidazole, neomycin and vancomycin reduces the total number of bacteria and dramatically changes the composition of the gut microbiota.
In addition to direct actionantibiotics can also indirectly weaken the gut microbiome. Symbiosis and interdependence are common in different subgroups of the gut microflora.
Under normal physiological conditions, the microbiota maintains a homeostatic state. Secondary metabolites produced by some species of microbiota may be essential nutrients for other species.
For example, Bifidobacterium adolescentis are able to use fructo-oligosaccharides and starch to produce lactate and acetate. Butyrate-producing anaerobes cannot use fructo-oligosaccharides and starches directly, but they can use lactate and acetate as growth substrates.
Therefore, B. adolescentis may facilitate the multiplication and expansion of butyrate-producing species in vivo through cross-feeding. Likewise, some substances are toxic to some commensal bacteria but non-toxic to others, which metabolize them, neutralizing the risk to other subgroups.
Other effects of antibiotics
The negative effects of using antibiotics, in addition to the most obvious ones, i.e. killing "good" bacteria, include:
- increase in the amount of bacteria resistant to antibiotics in the microbiome,
- changes in bacterial metabolites, which directly affects the host's he alth,
- disrupted bacterial signaling and secretion of antimicrobial peptides,
- dysregulation of the intestinal immune cells.
Even after the microbiota multiplies and recovers its total number of bacteria, it can have long-term effects on its balance, and consequently on the patient's susceptibility to infections and diseases.
Research shows thatafter taking antibiotics, the microbiome does not recover for at least 5 months.
Antibiotic diarrhea
The most common side effect of antibiotics is diarrhea. It results directly from the disturbance of the microbiome homeostasis caused by the drug used - changes in the diversity and abundance of intestinal bacteria.
As a consequence, it reduces the ability of the microbiota to inhibit the invasion of pathogenic bacteria and the overgrowth of pathogens, which are a component of the microbiome, but do not cause disease in small amounts.
Diarrhea appears most frequently with the use of broad-spectrum antibiotics, which clearly indicates that it is associated with the loss of a large and variable amount of commensal bacteria.
Numerous studies have confirmed that taking probiotics during antibiotic therapy reduces the incidence of antibiotic diarrhea.
How to care for the microbiomeduring antibiotic therapy - probiotics
The basic element supporting a he althy microbiome is the use of probiotics. Probiotics are "live microorganisms that, when administered in appropriate amounts, provide he alth benefits to the host."
The primary benefit of probiotics is that they contribute to the maintenance of a balanced microbiota and thus create a favorable gut environment.
The positive effect of probiotics on the gut microbiota in a variety of conditions (infectious and antibiotic-related diarrhea, irritable bowel syndrome, necrotizing enterocolitis, etc.) has been evaluated in a number of randomized controlled trials.
Taking probiotics is a basic strategy that reduces the negative effects of antibiotics on the microbiome.
Probiotics can counteract pathogenic microorganisms in different ways:
- competing with pathogens for nutrients and adhesion sites on the gastrointestinal mucosa,
- preventing pathogenicity by disrupting signaling between pathogens,
- by producing metabolites with antibacterial activity against pathogenic microorganisms,
- modulating and stimulating the local and systemic immune responses in the patient.
Probiotics that demonstrate the effectiveness in reducing antibiotic diarrhea proven by scientific research, and therefore effectively support the intestinal microbiome are:
- Lactobacillus rhamnosus GG in a dose of at least 2 billion CFU (colony forming units, it is a measure of the number of microorganisms).
- Mixed preparations containing different strains at a dose of at least 1.1 billion CFU of each strain. There were 4 or more strains in effective formulations. Strain examples:
- Lactobacillus acidophilus,
- Lactobacillus paracasei,
- Lactobacillus plantarum,
- Lactobacillus rhamnosus,
- Bifidobacterium bifidum,
- Bifidobacterium lactis,
- Bifidobacterium longum,
- Enterococcus faecium,
- Saccharomyces boulardii.
- Danone "Actimel" dairy product containing Lactobacillus casei DN-114001.
Probiotics should be taken at least 2 hours after the antibioticso that the drug used does not destroy the probiotic bacteria supplied. These are general recommendations, but there are probiotics on the market that should be taken simultaneously with the antibiotic.
Before starting use, read the recommendations in the leaflet, and preferably consult a doctor.
Probiotic preparations are good to take not only during treatment, but to continue them even for a month after the end of antibiotic therapy . When there are gastrointestinal symptoms related to diarrhea, indigestion or flatulence, prolonged use of probiotics is recommended.
How to take care of the microbiome during antibiotic therapy - prebiotics in the diet
Diet can influence the composition of the microbiome both positively and negatively. Some compounds called prebiotics have a unique influence on the growth of certain beneficial microorganisms.
By definition, a prebiotic is a substrate that is selectively used by the host's microorganisms and has he alth benefits. Prebiotics can increase the proliferation of beneficial microbes to maximize lasting changes in the human microbiome.
For this reason, increasing the proportion of prebiotics in the diet during antibiotic therapy is very beneficial.
Prebiotics have a positive effect on the microbiome in several ways:
- providing nutrients used by commensal bacteria, and thus promoting their multiplication,
- by increasing the proliferation of commensal bacteria, they promote a greater production of their metabolites, which have a positive effect on the intestinal environment and expression of host genes,
- as a substrate for the production of short-chain fatty acids,
- by blocking the adhesion of pathogens to the intestinal surface.
Prebiotic food ingredients fall into several groups. These can be non-digestible carbohydrates in the digestive tract:
- oligosaccharides and polysaccharides,
- resistant starch,
- algae.
- polyphenols.
The most studied prebiotics arenon-digestible carbohydratesor only partially digested in the digestive tract. They are found mainly in the cell walls of plants.
Prebiotics in this category are included in the dietary fiber. The very increased consumption of fiber from vegetables, fruits and whole grain cereal products (bread, wholemeal pasta, groats, cereals) has a positive effect on the microbiome.
However, some foods are rich in fiber fractions that are especially positive.
Polyphenolsare natural plant metabolites known primarily for their antioxidant and anti-inflammatory properties. Recent years of research have brought information that some of them also have a prebiotic effect.
Prebiotic polyphenols can be found, among others in:
- cranberries,
- darkberries,
- grapes,
- soi,
- tea,
- cocoa.
Resistant starchis a type of starch that is not digested by enzymes in the digestive system. It occurs in cooked seeds:
- legumes,
- cooked and then chilled potatoes,
- rice,
- macaroni,
- kasach,
- in unripe bananas,
- raw grain products such as oatmeal and rye.
Sources of prebiotics in the diet
| Fruits and vegetables | chicory, onion, garlic, Jerusalem artichoke, tomatoes, bananas, artichokes, leek, asparagus, apples, beets, fennel, peaches, nectarines, watermelon, dark berries, seaweed |
| Cereals and seeds | Wheat, barley, oats, linseed, corn, cocoa |
| Resistant starch | Cooked legumes, cooked then chilled potatoes, rice, pasta, groats, unripe bananas, unprocessed oatmeal, rye, barley |
| Drinks | Green tea, Pu-erh tea |
Fermented foods and the microbiome
Products fermented by beneficial bacteria include:
- yoghurts,
- kefir,
- sauerkraut and pickled cucumbers,
- other pickled vegetables and pickled lemons (not very popular in Poland),
- kimchi - fermented Chinese cabbage, turnips and cucumber,
- kombucha - sweet tea fermented by the so-called tea mushroom,
- tempeh - A fermented soy product popular in Indonesian cuisine and vegan diets.
Fermented foods are commonly considered to be as effective as probiotics. However, this is not true. They do not have the ability to populate the intestine and restore the balance of the microbiome.
However, due to the fact that they contain commensal bacteria (mainly Lactobacilli), they can be helpful in reducing the negative effects of taking antibiotics on the microbiome. Scientific research shows, above all, the effectiveness of yoghurts in this aspect.
What diet with antibiotics?
During and after treatment with antibiotics, you need to take care of a varied diet rich in vegetables, fruits and whole grain preparations. It's best to limit sugar, grocery store sweets and artificial sweeteners as they weaken the microbiome.
It is very important to include foods that provide prebiotics in your daily diet. It also doesn't hurt to drink yoghurt and kefir and eat pickled vegetables.The diet must be enriched with probiotic supplements.
How to take care of the gut microbiota - lifestyle
The balance of the microbiome is also dependent on other factors, not only diet and probiotic intake.
To support commensal intestinal bacteria:
- do not smoke,
- avoid alcohol,
- engage in regular physical activity (it does not have to be a competitive sport, walks are enough),
- get some sleep,
- avoid chronic stress.