Probiotics are certainly in the news more than they used to be. You probably see ads for probiotic products quite often. But how do you know which probiotic strains your body needs? What do the different types of probiotics do?

Probiotics are usually bacteria, but in all cases they’re live microorganisms that have similarities to those beneficial microorganisms that live naturally in the human digestive tract. They are “good bacteria”, which can prevent or lessen the symptoms of many health conditions.

More than 500 species of bacteria live in your gut. That’s a lot of bacteria. They facilitate digestion, provide nutrients and help to form your immune system. About 10% of your daily energy needs may be derived from good gut bacteria byproducts.

Probiotics boost your immune system, and when they are present in abundance, it’s more difficult for “bad” bacteria to cause disease, since they’re outnumbered.

What is even more interesting is that different strains of probiotics have different health benefits. That means it’s essential that you choose the right probiotics for you and your specific health needs. To help you do so, here’s a roundup of the most well-known probiotic strains and their various health benefits.

Ready to meet your probiotic soul gut mate? Use the quick navigation below to scroll to the one of your choice!

Quick NavigationLactobacillus Species L. acidophilus L. rhamnosus L. casei L. plantarum L. gasseri L. salivarius L. paracasei L. reuteri L. brevis L. helveticus L. fermentum Bifidobacterium Species B. bifidum B. longum B. infantis B. lactis Bacillus Species B. coagulans B. clausii Streptococcus Species S. thermophilus S. salivarius M18 S. salivarius K12

Lactobacillus Species

These are the most important group of the bacteria in your small intestine. They produce lactase, which breaks down sugar in milk, and ferment the carbs you take in to produce lactic acid.

Lactic acid creates an acidic environment in your digestive tract, making it an inhospitable place for unhealthy microorganisms to thrive, and also helps your body to absorb important minerals, like iron, magnesium, copper and calcium.

Below, we’ll look at the different species of lactobacillus bacteria and how they help you to remain healthy.

L. acidophilus

This is quite possibly the most vital strain of Lactobacillus bacteria. It congregates densely in your intestine, and helps to maintain intestinal wall integrity. It also supports your digestive function and ensures proper nutrient absorption.

It’s also helpful in easing digestive discomfort. A study of this probiotic shows that it can alleviate occasional diarrhea and when paired with B. bifidum, acidophilus is also helpful in modulating the response of intestinal flora to adverse antibiotic effects. Other benefits of L. acidophilus include its help with vaginal and urinary tract health for women.

Acidophilus aids in improving cholesterol and blood pressure. It fights fungal and bacterial infections and reduces the severity of symptoms in allergies.

It’s best for…

Overall digestion
Diarrhea relief
Protects intestinal flora from antibiotics
Vaginal and urinary tract health in women
Cholesterol and blood pressure
Fungal and bacterial infections
Allergy relief

L. rhamnosus

This strain of probiotics is able to survive passing through the entire GI tract. For this reason, it is believed to be one of the best probiotic strains in improving vaginal health. It is helpful in decreasing irritation of the vaginal area. It’s also helpful with weight loss.

As if probiotics knew they were traveling when you do, L. rhamnosus appears to love to travel to foreign lands. Research on this strain revealed that Americans who traveled from New York City, NY to a developing country had only a 3.9% rate of diarrhea after taking L. rhamnosus, as compared to the 7.4% rate for people who made the same type of trip without taking any probiotic.

It’s best for…

Preventing travel-related diarrhea
Vaginal and urinary tract health in women
Weight loss

L. casei

Lactobacillus casei is a superstar on the probiotic team. Research shows that it helps with diarrhea in children. Its other benefits include increasing immunity to disease, improving digestion, improving cholesterol levels and reducing allergies.

This probiotic is also used in making some tasty foods. It is part of making yogurt, cheese and other products made with fermented milk. L. casei is only a transient bacterium in your body, but it is a probiotic native to cattle. It is found naturally in raw cow colostrum and milk.

It’s best for…

Overall digestion
Boost immunity
Allergy relief
Improve cholesterol levels

L. plantarum

L. plantarum produces hydrogen peroxide. Your body can use this to defend itself from bacteria found in food, and against other harmful microorganisms. Research shows that this particular strain is especially effective in assisting the immune system of healthy adults. It’s also helpful for digestion.

In the research mentioned above, it was shown that in humans who have been infected with HIV, the primary location of immune activity is in the gut. The cells of the immune system, boosted by L. plantarum, can attack HIV.

Otherwise, the bad bacteria results in the sloughing of intestinal lining, which shows itself as severe diarrhea. When the gut lining is damaged, other species can invade, which results in AIDS defining illnesses like Cryptococcosis. L. plantarum can reduce or even destroy IL-1β, which resolves the inflammation and accelerates the self-repairing faculties of the gut.

It’s best for…

Overall digestion
Boost immunity
Reduce bloating and gas
IBS relief

L. gasseri

This is among the newer discoveries in probiotics. It is linked primarily to microflora that grows in the vaginal area. If you are a woman who tends to have vaginal discomfort, supplementing with this probiotic may help to improve your symptoms, since women with normal vaginal health have higher levels of this probiotic in their systems.

L. gasseri is also supportive of digestive health. Research has shown that supplementing your diet with both B. longum and L. gasseri aid in limiting the occurrence of occasional diarrhea for adults. It has also been linked to weight loss in adults.

It’s best for…

Weight loss and reducing belly fat
Vaginal health in women and reduced menstrual pain
Improve cholesterol levels

L. salivarius

This strain of probiotic is found naturally in your throat, sinuses and mouth, as well as in the vagina and intestines. It grows most easily within the confines of the small intestine.

Research shows that L. salivarius causes increased immune activity. When you supplement with this probiotic, it will aid in the prevention of colonizing “bad” bacteria. L. salivarius is also helpful with dental health and immune system health.

It’s best for…

Overall digestion
Boost immunity
Improve dental health

L. paracasei

This probiotic is naturally found in your small intestine but if you take it along with milk protein to increase its resistant to stomach acids, it can colonize in the colon as well.

L. paracasei helps in supporting proper liver function in the body, and a randomized study proved that supplementing with this probiotic and fiber improves liver function and lowers the pH of urine in half of those subjects tested. This probiotic also helps in fighting fatigue and can be effective for relieving symptoms of chronic fatigue syndrome.

It’s best for…

Liver health
Infant diarrhea
Improve energy levels and chronic fatigue syndrome

L. reuteri

This probiotic is not as well-known as most others. It colonizes in the mouth and the intestine. It has been shown in human trials to be supportive of immune, digestive and oral health. As an anti-inflammatory, it helps your gut health by increasing the availability of vitamin D, as it lowers cholesterol and fights the growth of candida.

L. reuteri is helpful in treating diarrhea, especially in children. It decreases the length of time people suffer with diarrhea. If you supplement your child’s diet with this probiotic, it will help in preventing diarrhea in the first place. This probiotic also helps in treating against colic in infants, and can help in the prevention of peptic ulcers.

It’s best for…

Overall digestion
Oral health
Reducing diarrhea
Candida infections

L. brevis

L. brevis gives your digestion system valuable anti-inflammatory benefits. One study offered proof that patients with Behcet’s syndrome supplementing with L. brevis could control oral ulcers often associated with this disease.

As a lactic acid bacterium, L. brevis has shown that it can displace harmful bacteria, and it even showed anti-cancer activities in a recent study. It helps older people increase their cellular immunity.

Women in their child-bearing years usually have higher amounts of L. brevis in their vagina. This probiotic is useful in the prevention of urinary tract infections.

It’s best for…

Immunity and anti-inflammatory benefits
Vaginal and urinary tract health in women

L. helveticus

This probiotic has shown in research that it helps in the reduction of high blood pressure. It is used often in Switzerland, and is sometimes even used to culture Swiss cheese. L. helveticus can improve sleep duration and quality, increase the levels of serum calcium in the blood, decrease PTH from bone loss and assist in the production of ACE-inhibitors.

L. helveticus supports the response of the immune system, and displaces bad bacteria as it colonizes the intestines. As it does so, it improves good (HDL) cholesterol and supports the digestive tract.

It’s best for…

Overall digestion
Boost immunity
Sleep issues
Bone density
Improve blood pressure levels

L. fermentum

This strain of probiotics is found in kimchi and sourdough. It produces antioxidants that are helpful in neutralizing the toxic products formed in the intestinal tract when you are digesting food. It can also exhibit activity that fights foodborne pathogens. L. fermentum is very useful in improving detoxification and overall digestion.

This probiotic enhances the work done by antioxidant enzymes, your resistance to infection by E. coli and your overall immune response. It also helps to alleviate occasional bloating and gas.

It’s best for…

Overall digestion
Boost immunity
Detoxification
Reduce bloating and gas

Bifidobacterium Species

Billions (literally) of Bifidobacterium can be found lining the large intestine walls, helping to ward off many harmful, invasive microorganisms and bacteria like yeast. These bacteria produce helpful lactic acid, which provides nearly 70% of the energy your cells need to line the walls of the intestine. This enhances your body’s natural barrier of protection in the digestive tract.

Lactic acid is also helpful in keeping the large intestine’s pH acidic, which discourages bad bacteria growth. An environment lower in pH also facilitates your body’s ability to absorb beneficial minerals, including iron, zinc, magnesium, copper and calcium.

B. bifidum

B. bifidum is one of the first probiotics your guts ever became home to and throughout your life, it will continue to be among the main good flora in your large intestine. It helps in the promotion of bacterial balance and prevents growth of “bad” bacteria, yeasts and molds. It does this by adhering naturally to the mucosa in the intestines.

This probiotic helps your body to break down protein, complex carbohydrates and fat. It produces beneficial enzymes that break down large molecules into a smaller size that your body can use more efficiently. A human trial has shown that this probiotic helps to alleviate diarrhea, particularly when you travel.

It’s best for…

Overall digestion
Nutrient absorption
Boost immunity
Prevent diarrhea and travel-related bad bacteria

B. longum

B. longum is a common strain of probiotics in the gastrointestinal tract. It scavenges and neutralizes toxins in the intestines and breaks down carbohydrates. Preliminary research has shown that this probiotic scavenges free radicals and helps the body chelate metal ions, particularly copper ions.

This probiotic supports immune health and aids in overall digestion. It also is an integral part of the health of your immune system. B. longum helps alleviate diarrhea associated with taking antibiotics, and lessens seasonal allergy symptoms. It may help in weight management programs. It contributes to better bone health and helps in the prevention of colon cancer.

It’s best for…

Overall digestion
Detoxification
Allergy relief
Prevent diarrhea
Bone density
Weight loss

B. infantis

This strain of probiotics is the single largest beneficial bacteria population in babies. The amount in your gut will decline as you age, but it still will remain a vital part of your microflora. Supplementing a healthy diet with B. infantis has been proven in a study to decrease the difficulty of bowel movements, and associated bloating.

If you keep your B. infantis levels balanced, you will experience less discomfort after you eat, and have an active metabolism and better health overall. Research in the UK has shown that women who took B. infantis for only a month experienced a lessening of IBS symptoms.

It’s best for…

Overall digestion
Promote regularity
IBS relief

B. lactis

This helpful probiotic is quite powerful. It fights the growth of tumors. It also enhances your immunity, helps in lowering cholesterol and improves your digestion.

Research has shown that B. lactis inhabits the colon and intestines in impressive numbers. It breaks down waste in the body and aids your body in absorbing of important vitamins & minerals. It improves the comfort of general digestion, decreases lactose intolerance, decreases the permeability of the intestine, normalizes bowel movements, decreases constipation and IBS symptoms, and treats acute diarrhea.

In addition to being helpful in digestion, B. lactis helps your oral health. It decreases the bacteria in the mouth that cause cavities. It also reduces the severity and frequency of respiratory problems, and increases immunity among geriatric patients.

B. lactis inhibits the growth of H. pylori, which can cause ulcers, reduces instances of the flu and colds, reduces inflammation and allergies, and decreases dermatitis sensitivity and symptoms. In patients with diabetes, this probiotic increases the control of blood glucose levels. It improves cholesterol levels by increasing good (HDL) cholesterol and decreasing overall cholesterol.

It’s best for…

Overall digestion
Immunity and anti-inflammatory benefits
Nutrient absorption and waste elimination
Lactose intolerance
Oral health
Ulcer prevention
Skin conditions
IBS relief

Bacillus Species

Bacillus are “good” bacteria, shaped like rods and bearing spores, and they produce lactic acid. They are resistant to light, heat and moisture, which means they can work in the acidic environment of the stomach. They also colonize readily in your small intestine. Since bacillus are excreted only slowly, they remain in the body for longer time periods than many other bacteria.

B. coagulans

Like other bacteria that produce lactic acid, B. coagulans produces enzymes that are helpful in digesting lactose. It improves your body’s ability to properly utilize iron, calcium and phosphorus. It also stimulates gastric motility and gastric juices.

This particular probiotic strain supports women’s vaginal health. One study showed that women taking B. coagulans every day had improvement in the pH level of the vagina, and 91% of patients found relief from their vaginal discomfort through the daily use of this probiotic.

B. coagulans is one of the more powerful strains of probiotics. It can help in fighting off invasive pathogens and viruses. It usually resides in your digestive tract, and can decrease the symptoms of IBS, including bloating and abdominal pain. It is also used to offer relief from the effects of occasional constipation.

It’s best for…

Overall digestion
Nutrient absorption
Lactose intolerance
Vaginal pH and health for women
Boost immunity
Constipation
IBS relief

B. clausii

This probiotic strain lives naturally in soil. However, it has been studied for use in easing respiratory infections in children. It also has shown promise in fighting the effects of gastrointestinal disorders.

B. clausii produces antimicrobial substances that have been shown in a scientific study to act effectively against some harmful bacteria, including Clostridium difficile, Staphylococcus aureus and Enterococcus faecium. This means that it has effective immunomodulatory and antimicrobial activities, and is effective against the invasion of negative bacteria like Caco-2 cells and Vero cells.

It’s best for…

Overall digestion
Respiratory infections
Boost immunity and anti-microbial

Streptococcus Species

Streptococcus species have more strains than disease-causing bad bacteria. There are probiotic “good” bacteria that can help to prevent disease. They are lactic acid bacteria, and ferment glucose into lactic acid.

Streptococcus probiotics are found in your mucus membranes and even on your skin. They can also relocate to tissues deeper in the body. The subtle differences between good and bad strains allow you to understand which strains are probiotics. These strains prove themselves helpful in warding off disease and in fighting disease once it has breached your body’s defenses.

Bacillus includes parasitic and nonparasitic species. In addition to the few types in the human body, many bacillus bacteria grow in soil, and are used as pesticides and growth additives for plants.

S. thermophilus

S. thermophilus is a powerful strains of probiotics, with multiple benefits to your health. It is found naturally in the colon, where its immunity and digestive benefits are most often seen.

This probiotic produces lactase, helping people to more efficiently digest milk. It is useful in its production of antibiotic chemicals that prevent infections like pneumonia. S. thermophilus also helps in the prevention of ulcers.

It’s best for…

Reduce diarrhea associated with antibiotics
Prevention of ulcerative colitis
Decrease symptoms of IBS
Increase HDL (good) cholesterol
Reduce atopic dermatitis symptoms
Increase anti-tumor activity
Decrease colic in babies

S. salivarius M18

This probiotic is found mainly in oral mucosa and it produces bacteriocin-like inhibitory substances (BLIS). It is especially active in specific areas on your teeth and gums. It promotes a healthy inflammatory response there.

Research has shown that S. salivarius M18 produces benefits in the mouth because its bacteriocins target Streptococcus mutans and the enzymes urease and dextranase, which otherwise promote the accumulation of dental plaque. In that double-blind study, 100 children were treated with M18 for three months, and sat the end of that time, oral plaque scores were much lower in the group given M18.

It’s best for…

Protect teeth and gums, prevent plaque

S. salivarius K12

This probiotic strain is found mainly in the oral cavity’s mucus membranes and produces BLIS, similar to the effects of S. salivarius M18, which inhibit the ability of other undesirable bacteria to grow.

In research, it was discovered that about 10% of the population carry BLIS-producing oral bacteria strains naturally, and they have fewer incidences of sore throat than the rest of the population. In addition, S. salivarius K12 offers children better ear health and increases the levels of interferon gamma (which signals positive immune response) and a reduction in sulfur compounds that can otherwise cause bad breath.

It’s best for…