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Health benefits of probiotics

What are the health benefits of taking probiotics?

Maintaining a healthy body is a delicate balance of many different types of nutrients. Each one, whether it’s a vitamin, mineral or macronutrient, plays a specific role in keeping all the different systems in your body functioning optimally.

Probiotics are just one part of what keeps your digestive system healthy. They are microbes that live primarily in the gut and they act in several different ways to keep your microbiome balanced and operating effectively.

By keeping a healthy balance of microbes in your gut, probiotics offer several different preventative and restorative health benefits.

What are probiotics?

Your body contains lots of different microbes, including bacteria, that help to keep your gut and your overall digestive system healthy and balanced.

Traditionally, we think of bacteria as a negative thing that brings disease. But bacteria play an important role in your health. Probiotics are live bacteria and yeasts that naturally occur and live in the body. For that reason, they’re often referred to as “good bacteria.” Probiotics primarily occur in the large intestine but are also found in your:

  • Mouth
  • Urinary tract
  • Skin
  • Vagina
  • Lungs

Essentially, anywhere that your body comes into contact with the outside environment is a place where you’ll find probiotics. 

Probiotics can be ingested naturally through different types of food, particularly fermented food. For example, yogurt and yogurt drinks are often recommended to raise your probiotic levels. 

What probiotics do

Research is still ongoing into exactly how probiotics behave within the body. But what is known is that they work in two primary ways. 

Firstly, they help to fight off “bad bacteria” that make their way into your gut. These are the types of bacteria that can cause disease, infection or an upset stomach. Maintaining this balance within your gut is the primary role of probiotics.

Certain medical situations result in a lower count of good bacteria in your body. For example, taking a course of antibiotics can have the side effect of eliminating a lot of good bacteria, too. In those instances taking supplements or eating probiotic-rich food can help to restore your probiotic levels.

Probiotics also participate in lots of day-to-day operations within your body that are critical to your overall long term health, including:

  • Aid in the breakdown and digestion of food,
  • Balance out levels of bad bacteria,
  • Support the absorption of vitamins,
  • Bolster the cells that line the stomach and gut to prevent bad bacteria absorption into the blood, and
  • Digest and absorb medication.

Lastly, probiotics help to support the overall functionality of your immune system and regulate inflammation in the body.

Different types of probiotics

The term “probiotics” is used to refer to many different types and classes of healthy bacteria and yeast in the body. Each probiotic carries different benefits but they can be classified into three main categories.


Lactobacillus is the most common group of probiotics and can be found in fermented foods such as yogurt and cheese. It helps us to break down lactose, which is why it can be beneficial for preventing and treating diarrhea, particularly for those who suffer from lactose intolerance.


Bifidobacteria primarily live in the stomach and gut. They help to fight off bad bacteria in the gut and ease digestion. It’s particularly related to easing digestive issues such as irritable bowel syndrome, among others. It can be found in fermented foods such as dairy as well as some cured meats.

Saccharomyces boulardii

This microbe is a type of yeast. Saccharomyces boulardii has been linked to alleviating symptoms of inflammatory conditions in the stomach and bowel. One study published by the National Institutes of Health found strong links for the efficacy of saccharomyces boulardii in treating and alleviating the symptoms of conditions including:

  • Crohn’s disease
  • Ulcerative colitis
  • Irritable bowel syndrome
  • Parasitic infections
  • Helicobacter pylori infection
  • Clostridium difficile infection
  • Different forms of diarrhea including traveler’s diarrhea, acute/persistent diarrhea and antibiotic-associated diarrhea  

Health benefits of probiotics

Relieving antibiotic side effects

The purpose of antibiotics is to kill infections caused by bacteria in the body. Unfortunately, they can also have the side effect of killing good bacteria in the body. This imbalance can then lead to extended side effects such as fatigue and diarrhea. Taking probiotics alongside your antibiotic medication helps to maintain and restore balance to alleviate common side effects associated with taking a course of antibiotics.

Treating lactose intolerance 

Lactose is a type of sugar found in dairy products. Lactose intolerance is very common in humans and can affect us to varying degrees. Lactose intolerance causes side effects such as intestinal gas, constipation and diarrhea.

Probiotics, particularly lactobacillus, helps to break down lactose more effectively in the digestive tract, thereby alleviating and preventing some of these symptoms.

Treating diarrhea 

There are many different causes of diarrhea. Everything from infectious bacteria to stress can impact our gut and cause digestive problems. 

Strong links have been discovered between probiotic treatment and the alleviation of many different types of diarrhea. For people who suffer from acute or chronic diarrhea (such as sufferers of irritable bowel syndrome) probiotics can bring relief to symptoms and help to prevent further incidents.

Allergy prevention

Several studies have been conducted to establish a link between probiotics and the prevention of allergic reactions. Research has found that probiotics contribute to allergy prevention in two main ways, particularly food allergies and atopic dermatitis. They also contribute to the production of gut and lung mucous that help to moderate allergic responses. 

Probiotics foods

You can increase your levels of probiotics through food and drink or the intake of probiotic supplements.

Foods that are good sources of probiotics include:

  • Yogurt
  • Some types of cheese (such as Swiss, cheddar and cottage)
  • Kefir
  • Sauerkraut
  • Tempeh
  • Pickles
  • Sourdough bread

Drinks that are good sources of probiotics include:

  • Kombucha drinks
  • Kefir
  • Probiotic yogurt drinks

Aside from food and drink, you can also add probiotic supplements to your diet to boost your levels of good bacteria. Probiotic supplements may come in the form of probiotic pills, probiotic powders and probiotic drinks. For more information on probiotic supplements, check out the full buying guide from BestReviews.

Can anyone take probiotics?

As with any supplement, it’s a good idea to consult your doctor first. This may be particularly important with probiotics since the FDA regulates them as a food rather than a medication. This means that manufacturers and sellers of probiotics and probiotic supplements are not required to show that the supplements are safe. They’re also not required to prove the efficacy of their supplements.

Some people can experience side effects when they increase their intake of probiotics. These side effects can include increased gas, diarrhea or other types of stomach upset. If these side effects don’t settle down after a couple of days, it’s a good idea to stop taking them and consult with your physician.

If you suffer from existing digestive issues or autoimmune disorders, probiotics may not be suitable for you to take. 

Best probiotic supplements

Probiotic 40 Billion

This strong slow-release probiotic supplement is designed to penetrate deep into the large intestine for improved digestive health and immune support.

Where to buy: Sold by Amazon and iHerb

Garden of Life Raw Probiotics for Women

This probiotic supplement is specifically designed for women to support their immune system, digestive functionality and vaginal health. 

Where to buy: Sold by Amazon and iHerb


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Lauren Farrell writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.


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