What Are Probiotics?

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What Are Probiotics?

PlushCare Content Team

Written by PlushCare Content Team

PlushCare Content Team

PlushCare Content Team

The PlushCare team is composed of medical doctors, registered nurses, and health experts who enjoy writing about health topics. Our content is reviewed by our team of medical professionals to ensure accuracy.

July 8, 2021 / Read Time 5 minutes

Probiotics have become a bit of a craze over the past few years, with probiotic supplements and fermented products like kombucha and sauerkraut becoming more and more popular. But what ARE probiotics, and are they actually good for you?

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What Does Probiotics Do?

Probiotics are bacteria that promote health in their host (the human they live in or on). Humans are naturally completely covered in probiotics (“good” bacteria), from the skin on our bodies to the inner linings of our intestines.  We usually don't notice these bacteria at all, but we do know that they help our immune systems function at their best. The “good” bacteria that we live with can help keep out other bacteria that can cause disease and infections.

What Are Probiotics Used For?

Probiotics are used to achieve a healthy balance of bacteria in the digestive system, which helps promote overall health and reduces the risk of certain diseases. Research has shown that probiotic supplements have been associated with a wide range of health benefits:

  • Taking probiotics might help prevent or alleviate the diarrhea that people sometimes get after taking antibiotics.

  • People with infectious diarrhea (such as traveler's diarrhea) might recover more quickly if they take probiotics.

  • People with inflammatory bowel disease (Crohn's disease or ulcerative colitis) and people with inflammatory bowel syndrome (IBS) might have less severe symptoms or fewer relapses if they take probiotics.

  • Some people with allergic rhinitis (hay fever) or eczema may have fewer symptoms if they take probiotics.

  • People who have had surgery on their gastrointestinal (GI) tract might develop inflammation in their intestines after surgery. Some of these patients have a smaller chance of developing GI tract inflammation if they take probiotics.

As you can see, the medical research on the benefits of probiotics is pretty scant and focused on a few conditions. While probiotics should not do much harm to someone with a normal immune system, probiotic pills are not regulated by the Food and Drug Administration (FDA). In other words, companies that sell probiotics do not need to prove that the pills actually contain any of the ingredients listed on the bottle. In some cases, these pills actually could contain “bad” bacteria, which could be dangerous, especially for people with weakened immune systems (such as people undergoing chemotherapy).

How Do Probiotics Work?

Research shows that probiotics can help balance “good” and “bad” bacteria in the digestive system to keep the gut healthy, support immune function. “When you are sick, bad bacteria enters your body and increases in number. This knocks your body out of balance,” according to Cleveland Clinic. “Good bacteria works to fight off the bad bacteria and restore the balance within your body, making you feel better.” Probiotics can also replace “good” bacteria lost in the body, for example, when taking antibiotics.

What Happens When You Start Taking Probiotics?

When you start taking probiotic pills, you may experience mild side effects, including gas and bloating. These side effects typically fade within 2–3 days of probiotic use. If you’re taking high-quality, multistrain probiotics, you may notice initial improvements and health benefits within 1–2 weeks. Depending on your digestive system and sensitivity, you may feel a difference within a few days of starting probiotic supplements.

How Do You Know If a Probiotic Is Working?

After starting probiotics supplements, many people notice positive changes, which can range from increased energy to clearer skin. In most cases, the first indication that your probiotic is working is improved digestion. When taking probiotics, it’s important to keep in mind that not all probiotics are the same, and different strains may have different effects on the body. “For example, one strain may fight against cavity-causing organisms in our mouths and don't need to survive a trip through our guts,” according to experts at Harvard School of Medicine. 

How Long Should You Take Probiotics?

Once your symptoms improve, you should stop taking probiotics. Because your body works to maintain a healthy balance of “good” bacteria in your gut, there’s no need to take probiotic supplements regularly. With that said, if you’re using probiotics to treat a medical condition, be sure to consult your doctor about your use of probiotics. Your doctor will be able to determine whether probiotic supplements may be helpful for your condition, which types of probiotics to take, and how long you should take them.

Probiotic Foods

The easiest way to obtain more good bacteria is to ingest it, usually in the form of foods high in probiotics, such as:

  • Yogurt

  • Fermented products, such as kombucha and kefir

  • Sauerkraut

  • Tempeh

  • Kimchi

With that said, it's not clear yet whether eating probiotics actually improves one's health. It's challenging to research the benefits of probiotics in yogurt or fermented foods, because any benefit we see from them could be attributed to the probiotics in the food or to any of the other ingredients. If you like these foods and you are able to digest them without any other symptoms, it's probably fine to continue eating them in moderation. However, if you are lactose intolerant, it's not a good idea to eat yogurt as a probiotic because the downsides of lactose intolerance outweigh any potential benefits of the probiotics you ingest.

Probiotics Side Effects

When first starting probiotics, some people may experience side effects. Probiotic side effects may include:

  • Gas, bloating, or diarrhea

  • Skin rash or itchiness

  • Increased risk of infection

  • Antibiotic resistance

Anyone with an allergy or intolerance to soy, eggs, dairy, or gluten should exercise caution when choosing probiotic pills. Stop taking probiotics and consult your doctor if you experience any allergy symptoms or serious side effects.

Should You Start Taking Probiotic Pills?

If you are healthy, you do not need to take probiotic pills to boost your body's natural bacteria or improve your immune system's function. It is fine to consume probiotics in foods like yogurt as long as you are able to digest those foods easily. [book_appointment]

Get a Probiotics Prescription Online

If you have a health condition that you think might improve from taking a probiotic, you should discuss this idea with your doctor to decide what type of probiotic would work best for you. As always, the online doctors at PlushCare are available to talk with you about any questions you have about your health or diet.  PlushCare’s top physicians will diagnose, treat, and prescribe you medication all from your phone. For more information or to book an appointment, visit plushcare.com.

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  • Cleveland Clinic. Probiotics. Accessed on April 16, 2021 at  https://my.clevelandclinic.org/health/treatments/14598-probiotics

  • Harvard Medical School. Health benefits of taking probiotics. Accessed on April 16, 2021 at https://www.health.harvard.edu/vitamins-and-supplements/health-benefits-of-taking-probiotics 

  • National Center for Complementary and Integrative Health. Probiotics: What You Need To Know. Accessed on April 16, 2021 at https://www.nccih.nih.gov/health/probiotics-what-you-need-to-know

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