Last updated: 16/10/2022

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In this latest guide, we’re going to introduce you to a very important, topical subject: the use of probiotics. Probiotics are commonly found in supermarkets and pharmacies as well as at herbalists, and they’re normally recommended for anyone who suffers from intestinal issues like abdominal bloating or flatulence. But there’s much more to know about this amazing supplement.

Probiotics can help restore the proper balance of microbial flora in people who are under stress, have a poor diet or take too many antibiotics. But taking probiotics requires some essential knowledge so that it’s done safely and successfully, so keep reading to get the full scoop.

Key Facts

  • Probiotic supplements contain living microorganisms that offer many great health benefits.
  • Different bacterial species and strains are available, with each offering the potential to treat specific symptoms or pathologies.
  • Consuming probiotics is considered safe for most of the population, but they can trigger infections in some immunosuppressed individuals.

Our Selection: The Best Probiotic Supplements

Were you aware that many “probiotics” available on the market actually have little to no usefulness? If you want to get the real benefits from this amazing supplement, you need to be careful to pick out safe and efficient bacterial strains from authentic brands. We’ve put together this list of some of the best probiotic supplements to make it easier for you. We hope you’ll find the right one for you needs!

Buyer’s Guide: Everything You Should Know About Probiotics

When we hear the terms “bacteria” and “microorganisms,” they often evoke thoughts of illness and disease. But the reality is that many microbes are part of our natural flora, and they offer numerous benefits to our health. If our body’s flora—also called microbiota—is dying, we can heal it with probiotics supplements.

woman getting out some productos from the freige

Most probiotics should be kept in the fridge.
(Source: Om: 25864227/

What exactly are probiotics?

Probiotics are a kind of dietary supplement that contain living microorganisms (bacteria or yeasts) capable of providing a beneficial impact on your health. The Lactobacillus and Bifidobacterium genera (bacterial classes) are the most common bacteria found in probiotics.

Probiotics are often confused with what are known as prebiotic supplements, which are non-living compounds that support an environment suitable for the growth of a healthy microbiota. Your normal flora gets energy from these carbohydrate compounds.

What are the necessary criteria for probiotic supplements?

Putting just any random bacteria in the human body won’t produce the positive results that we’re all looking for, and it could even harm you in some cases. So these are the criteria that probiotics must have in order to be sold on the market and consumed safely:

  • Scientific evidence: Recognized scientific studies must clearly indicate the effectiveness of probiotics.
  • Safety: The probiotic’s microorganisms must under no circumstances be aggressive or lead to infections in an otherwise healthy person.
  • Vitality: Any probiotic bacteria or yeast must remain alive while encapsulated, at least until the expiration date.
  • Survival: At least half of the probiotic’s microorganisms should survive ingestion, digestion or application of the product in order to arrive alive at their intended destination.
  • Labelling: The label providing crucial information about the probiotic should be clearly visible, easy to read and understandable.

Probiotic use has gained widespread popularity, with many pharmaceutical manufacturers developing new strains and claiming that they offer amazing benefits. As we mentioned, however, many of these products don’t meet the necessary quality standards. Always inform yourself about a product prior to buying it.

Kefir is a food that naturally has a high probiotic content.
(Source: Zidar: 34037457/

What are the benefits of probiotics?

The benefits seen from probiotics depends on the kind of strain that the specific supplement contains. Once the microorganisms colonize the target area (which could be the stomach, mouth, intestine or genitalia) they may begin to result in the advantages listed here:

  • Easier and faster digestion
  • Decrease in flatulence
  • Reduction of abdominal girth
  • Improvement of intestinal transit
  • Normalization of body weight and blood cholesterol levels
  • General improvement in symptoms of anxiety
  • Lower incidence of infection
  • Lower incidence of allergic reactions
  • Higher levels of folic acid, cyanocobalamin and vitamin K
  • Relief of pain linked to menstruation (in women)
  • Boosted fertility (in women)

Using probiotic supplements that include a number of bacterial species may help you to improve your overall quality of life. Still, we encourage you to look for probiotics with specific strains if you’re hoping to address specific issues you’re having. For example, there are products tailored to weight loss or building the body’s defenses against infection.

Ken LitwinBoard-Certified Physician in Sandy Hook, CT
“If you have a damaged or ‘leaky’ gut, probiotic supplements can help restore a healthy gut barrier. Healthy cut bacteria help to increase production of helpful nutrients, including vitamin K, folate and other important B vitamins.”

What are the different kinds of probiotics?

There are literally hundreds of different probiotics out there, so the best way to figure out which one is right for you is to identify the symptoms you’re trying to treat. The table below outlines different strains and the symptoms they may help with.

Symptom to treat Recommended probiotics (bacteria and strain)
Acute diarrhea (associated with gastroenteritis) Lactobacillus reuteri DSM 17938, Lactobacillus reuteri ATCC 55730, Lactobacillus rhamnosus GG, Lactobacillus casei DN-114 001, Saccharomyces cerevisiae boulardii CNCM I-7454 and Lactobacillus gasseri CP2305
Diarrhea (following medication use) Lactobacillus rhamnosus GG and Saccharomyces cerevisiae boulardii CNCM I-745
Heartburn (Helicobacter pylori infection) Lactobacillus johnsonii LA1 and Lactobacillus gasseri OLL2716
Constipation Lactobacillus reuteri DSM 17938, Lactobacillus reuteri ATCC 55730, Lactobacillus rhamnosus GG, Propionibacterium freudenreichii CIRM-BIA 129 and Lactobacillus gasseri CP2305
Irritable bowel syndrome Lactobacillus acidophilus AD031, Lactobacillus acidophilus SDC 2012,2013, Lactobacillus casei DG, Lactobacillus plantarum 299v and Bifidobacterium longum NCC3001
Common cold and viral infections Lactobacillus casei Shirota and Streptococcus salivarius K12
Cavities and gum problems Streptococcus salivarius M18
Obesity and high cholesterol Lactobacillus gasseri BNR17, Lactobacillus gasseri SBT2055 and Bifidobacterium animalis GCL2505
Symptoms of depression Bifidobacterium longum NCC3001
Symptoms of anxiety Lactobacillus gasseri CP2305, Lactobacillus rhamnosus NCC4007 and Bifidobacterium longum NCC3001

Although it looks like a lot, this table is really just a brief glimpse into the vast world of probiotics. For more in-depth information or to treat problems we didn’t mention, consult your doctor.

How should I take my probiotic supplement?

In order to keep the microorganisms in probiotics alive, there are a handful of guidelines to follow. Dead bacteria will be of no use in this situation. Here are some tips to get the most from your probiotic supplement:

  • When? You can take a probiotic at any time. However, we suggest it half an hour before a meal if the goal is to improve digestion.
  • How? Take your probiotic along with food or water. Try to avoid taking it with acidic foods or very hot liquids, since acid and heat can destroy the microorganisms.
  • How much? The dosage may vary according to the specific supplement, so be sure to check the label. The standard recommendation for first-time users of probiotics is 15 billion Colony Forming Units (CFU).

If you’re taking any antibiotics, be sure to wait at least two hours between those and your probiotic. The bactericidal substance present in antibiotics is harmful to probiotic microorganisms.

Dr. Whitney BoweBoard-Certified NYC Dermatologist and Expert in Skin Rejuvenation
“You can start with a probiotic containing 10 to 15 billion CFUs before gradually increasing the dose, as you may experience some swelling when your intestine is colonised again.”

How should I preserve a probiotic supplement?

Experts recommend storing your probiotics at low temperatures, but not in the freezer. The cold in your fridge will slow down the bacteria’s metabolism and increase their shelf life. On the other hand, heat and exposure to the sun can have the opposite effect.

Always keep an eye on a supplement’s expiration date of your supplement. Probiotics are only effective as long as they’re alive, which won’t be too long after the expiration date.

Your probiotic supplement should be in a container with a protective seal.
(Source: Boonpeng: 61822789/

What are the side effects of probiotics?

The sudden, quick growth of microbiota in the body is the primary cause of the most frequent side effects experienced alongside probiotic use. Symptoms may include flatulence, abdominal bloating and a feeling of heaviness in the stomach. The symptoms will, however, gradually subside with continued use of the supplement.

There have been some cases where probiotics resulted in severe infections. This rare complication appears in individuals who suffer from some kind of immune deficit or with an underdeveloped immune system. But in general, healthy people are unlikely to face any severe complications from the use of probiotics.

Andreu PradosPharmacist and Dietitian-Nutritionist
“Make sure any probiotic you want to use has been backed up by serious clinical trials. We always recommend evaluating the risks/benefits of a product in each person and obtaining the approval of your doctor and/or pharmacist.”

What are the contraindications of probiotics?

Various studies done in recent years have indicated that even high doses of probiotics are generally safe for human consumption. Still, special caution and prior medical monitoring are advised for the following groups:

  • Immunosuppressed individuals: Probiotic use is contraindicated in the case of immunosuppression caused by transplant, HIV infection or genetic alterations. That’s because the microorganisms may trigger sepsis—a severe infection that spreads throughout the body.
  • Babies: Some probiotics are specifically developed to treat diarrhea in infants. However, there have been isolated cases of sepsis reported in critically-ill newborns. For this reason, probiotic use in children should be closely monitored by a doctor.
  • Pregnant and breastfeeding women: Although you may find products tailored to pregnant women, always consult your doctor or midwife prior to adding any supplements during a pregnancy or while breastfeeding.
  • People with aortic valve implantation: Studies have shown evidence of endocarditis (a serious infection affecting the heart) brought on by the colonization of artificial valves by probiotic microorganisms. Those undergoing cardiac surgery should use probiotics with caution.

Even though infections resulting from probiotics are very uncommon, their consequences (sepsis, endocarditis and fungal invasion) can be very serious. Be sure to speak with a doctor and look for strains indicating expert-confirmed effectiveness to help you avoid any complications.

Some users experience allergy-like symptoms such as itchiness and skin inflammation following probiotic use.
(Source: Popov: 39679362/

What is the microbiota?

Microbiota is composed of bacteria and yeasts found in your skin, intestine and the genital tract of healthy humans. Microbiota helps prevent colonization by pathogenic germs, and it also offers many benefits to your health, such as easier digestion and the synthesis of certain vitamins.

According to a number of scientific studies, microbiota begins to develop in the hours following birth. During labour, a baby comes into contact with the maternal flora and certain microorganisms found in the external environment. The yeasts and bacteria colonize the newborn, resulting in the growth of a unique and personal microbiota.

The microbiota settles on the mucosal and surfaces that are in contact with the external environment, thereby forming the following microbiota: intenstinal, cutaneous, vaginal oral and ocular. The intestinal flora impacts the well-being of your whole body, which is why it’s considered especially interesting for supplementing.

Which microorganisms make up a normal intestinal microbiota?

Bilions of different bacteria are present in our intestinal microbiota. An individual’s diet and genetics, in addition to other environmental factors, impact the quantity and variety of the microbe species inhabiting that person’s intestinal tract. There are three primary bacterial divisions, also called phyla:

  • Firmicutes: This phylum makes up to 70% of all microorganisms in our normal microbiota. It includes the Lactobacillus bacteria, the most well-known of which is the Lactobacillus casei (L-casei immunitas).
  • Bacteroidetes: These represent 20% of the normal flora. The best-known bacteria of this phylum belong to the Bacteroides genus (Bacteroides fragilis, Bacteroides ovatus and Bacteroides dorei).
  • Actinobacteria: This group is much smaller (5%) than other phyla, but we find inside it the vital Bifidobacteria (“active Bifidus”).

Fermented foods are high in probiotics.
(Source: Madeleinesteinbach: 90447295/

What are the functions of the intestinal microbiota?

Microbiota are not confined only to your intestine and stomach. According to the most recent studies, the positive effects of microbiota can be felt throughout the body. Here are some processes that rely on intestinal flora:

  • Defense against harmful bacteria (pathogens): It prevents or hinders pathogenic bacteria from colonizing the gastrointestinal system and causing infections.
  • Metabolism and digestion: Microbiota bacteria allow some compounds present in food, such as starches, to be digested by humans. Our flora also play a role in synthesizing essential compounds like biotin, vitamin K and folic acid.
  • Regulation of immunity and inflammation: Bacterial species of our flora can regulate the body’s immune reaction, which reduces the inflammatory response and prevents potential intolerance and allergies.
  • Neuromodulation (“brain-gut-microbiome” axis): The complex neuronal network of our intestine is in direct contact with the brain. This relationship is affected by microbiota, which regulate the production of chemicals critical to the normal function of the nervous system.

The table below shows the most relevant impacts from the primary microbial bacteria:

Bacteria Phylum Function
Bacteroides fragilis Bacteroidetes Defense against harmful bacteria
Bacteroides melaninogenicus Bacteroidetes Defense against harmful bacteria
Bacteroides oralis Bacteroidetes Defense against harmful bacteria, metabolism and digestion
Bifidobacterium bifidum Actinobacteria Defense against harmful bacteria, regulation of immunity and inflammation, metabolism and digestion
Lactobacillus Firmicutes Defense against harmful bacteria, metabolism, digestion and neuromodulation
Prevotella Bacteroidetes Defense against harmful bacteria, metabolism and digestion

Which factors affect the composition of our intestinal microbiota?

Many factors affect the composition and variability of each person’s flora, creating an individualized intestinal microbiota. These are the main factors that can alter the number and proportion of your intestinal bacteria:

  • Anatomy: Conditions in the digestive tract (like alterations in the bile or gastric acid production) affects which kinds of bacteria become part of the normal microbiota
  • Age: Children have less diverse flora. New species of bacteria become present over the years.
  • Genetics: Relatives have presented similar microbiota; this is especially true for twins.
  • Medication: As mentioned earlier, the indiscriminate intake of antibiotics can have a negative impact on your flora.
  • Diet: Intense diets—like vegan or all-meat diets—can lead to the disappearance of certain species normally present in the flora. The intestinal bacteria can also be negatively impacted by the use of sweeteners.
  • Stress, anxiety and depression: Changes to the microbiota may accompany emotional stress and other mental alterations.
  • Toxins: Tobacco use can result in several changes to the variability of normal flora.

Your diet plays a crucial role in your well-being. If your diet is inadequate and contains too many fats, sugars and sweeteners, the proportion and quantity of the various populations of your flora may be altered, which can contribute to the onset of various unwanted conditions.

Did you know that the term “intestinal flora” is not quite accurate? Experts recommend using the term “microbiota” to refer to these microorganisms, since they don’t belong to the plant kingdom.

What are the consequences of an imbalance of the intestinal microbiota?

Intestinal dysbiosis is the primary change that takes place if the composition of your intestinal flora varies greatly from what is considered an appropriate bacterial balance for healthy people. This condition can lead to a long-term deterioration in overall health. Here are some of the primary symptoms:

  • Changes in digestion: You may experience difficulty digesting some compounds, like fibers. This supports the onset of constipation, abdominal discomfort, diarrhea and flatulence.
  • Overweight and obesity: Diets high in fat and sugar cause a rise in bacterial levels of the Bacteroidetes phylum. By increasing fat absorption, these bacteria contribute to the onset of obesity, hypertension and an increase in blood cholesterol levels.
  • Infections of the digestive tract: Intestinal dysbiosis promotes the formation of pathogenic or opportunistic bacteria. Normally harmless, these microorganisms take advantage of your weak defenses to become aggressive, potentially resulting in gastroenteritis, diarrhea and even colitis.
  • Inflammation: Studies have indicated that microbiota imbalance can lead to persistent inflammation. This can cause symptoms like flatulence and abdominal swelling. Other more serious repercussions have also been seen, such as heightened incidence of colon cancer.
  • Nervous system disorders: Dysbiosis can result in changes to the brain-gut-microbiome axis, causing and promoting a number of conditions impacting the nervous system (such as anxiety, depression and insomnia).

How can I increase growth of my intestinal microbiota?

The balance of intestinal flora is very delicate, and experts insist that the bacteria oscillate between resilience and fragility. Always be particularly careful with the factors listed below if you want to promote proper flora growth:

  • Balanced diet: Experts suggest that a diet low in fats and sugars helps the development of a balanced flora. Individuals with strict vegan, vegetarian or carnivore diets should be more careful in maintaining their intestinal microbiota.
  • Avoiding sweeteners and polyols: These days, many people try to decrease their sugar intake by using sweeteners like stevia or sucrose. However, the development of intestinal dysbiosis has been linked to such products; sugar and sweetener-free diets are considered to be healthier.
  • Increasing fermented food and fiber consumption: The growth of many microbiota species is promoted by fibers. Fermented products like yogurt, kefir, miso and kimchi contain microorganisms that can strengthen your intestinal microbiota when ingested.
  • Quitting alcohol, tobacco and other toxins: These toxic substances can alter and destroy your flora.
  • Adopting an eat-rest-exercise routine: Sticking to a regular eating schedule also favors your flora’s balance. Sleeping and exercising regularly as part of a healthy lifestyle creates an environment favorable to the growth of your microbiota.
  • Only using prescribed drugs: Alterations in your microbiota’s balance can be caused by antibiotics, and, to a lesser extent, other medications like anticonvulsants and neuroleptics. You should always speak with your doctor prior to taking any medication.

Shopping Criteria

Picking the right probiotic for your needs is never easy, but don’t worry: after reading the first part of our article, you now know a lot of crucial information about probiotics. Let’s now take a look at the shopping criteria, which will be key in your final decision:

Vegan or Vegetarian Nutrition

The substrate of most probiotics is of animal origin, so if you follow vegan or vegetarian diet, we recommend looking for supplements that feature a small vegan seal guaranteeing that the product is made from only plant sources.

The composition of the capsule itself is also relevant, since many capsules are made with gelatin. The good news is that you can now find vegan capsules made from cellulose.

Were you aware that vegetarian capsules are made from hydroxypropylmethylcellulose, a natural modification of cellulose?

Intolerances and Allergies

Factories where probiotics are manufactured may have gluten, lactose, nuts or fish present. If you have intolerances to any of these items, be sure to look for a  supplement with a label that clearly indicates no trace elements of allergens.

Number of Microbial Species

In just one probiotic capsule, you might find a single bacterial species (like Bifidobacterium animalis) or several genera (e.g., Bifidobacterium animalis and various Lactobacillus species). Nonetheless, some studies have indicated that taking just a single bacterium is the most effective approach.

Probiotics that include several bacterial species are more efficient for preventing potential infections; but if you have a specific goal in mind, we suggest looking for specific strains. Using Bifidobacterium animalis is, for example, more effective for the treatment of obesity.

Did you know that bacteria compete against each other for substrates (oxygen and food)? If several microorganisms are present in a single probiotic, they need to cooperate with each other. If not, the effectiveness of your supplement may be limited.


As we mentioned above, probiotics are very delicate, so you should always examine the packaging before you buy it. Any damaged container should be thrown away, because the microorganisms may die or be weakened from contact with air or light.

Quantity of CFU

Make sure the probiotic you pick has the desired amount of probiotic bacteria (measured in CFU). Look for supplements with the highest possible CFU quantity—between 10 and 15 billion—to ensure its effectiveness. That’s because some percentage of the microorganisms will likely die during packaging and ingestion.

Value for Money

Most probiotic supplements on the market will come with at least thirty (30) capsules or tablets. Studies have indicated that that the positive effects of probiotics appear after about a month of use, so we suggest that you purchase a larger quantity at the start, in oder to get the desired effect.


As you’ve learned in this article, your quality of life can be improved through supplementing with probiotics. These microorganisms help boost your defenses while also soothing gastrointestinal distress. If you’re already taking care of your external appearance with cosmetics and fitness, why not strengthen your inner health with probiotics?

Yes, preserving probiotics is much more complex and difficult than other common supplements like vitamins or minerals. Still, their benefits are worth it. So join in the craze and reap all the benefits of probiotics!

We hope you found our guide on probiotics helpful. Please leave a comment with your thoughts, and feel free to share our article with your friends on social media!

(Source of featured image: Zidar: 32277956/