1. Home
  2. Health Guides
  3. Probiotics: What they are, gut health benefits, and how to take them for best results

Probiotics: What they are, gut health benefits, and how to take them for best results

Reviewed By: Trevor Kirby, PhD, Principal Research Scientist, Research
4 MIN READ — 1 Citation — 05/21/2026

Probiotics for gut health are beneficial live microorganisms that help balance your microbiome, support digestion and immune function, and deliver the greatest benefits when you choose the right strains and take them consistently as part of your daily routine.

Key Takeaways

  • 01.

    Probiotics are beneficial live microorganisms that support digestion, immune health, and gut health. They’re commonly found in fermented foods and supplements and are generally safe and easy to incorporate into a daily routine.

  • 02.

    Probiotics support whole-body health by strengthening the gut and influencing the gut–brain connection.

  • 03.

    Not all probiotics are the same—different strains support different aspects of digestive health.

  • 04.

    The best results come from choosing high-quality, research-backed probiotics and pairing them with prebiotics. Prebiotics feed beneficial bacteria, helping probiotics work more effectively and sustain long-term gut health.

What are probiotics?

Probiotics are live microorganisms (often bacteria) that provide health benefits when consumed in appropriate amounts. They are generally safe to consume and can help with gut health, immune health, and support normal gut microbiome function.

How probiotics support gut health

Probiotics play an active role in maintaining and supporting your digestive health. From balancing your gut microbiome to supporting immune and brain function, they influence gut health in several important ways.

  • Transiently colonize and support a balanced intestinal microbial community. This can help support digestive health.
  • Probiotics support a healthy gut environment by competing to adhere to the gut lining, helping to limit unwanted substances from adhering, and producing organic acids that help maintain a balanced bacterial environment.
  • They support gut barrier function. Some probiotics promote mucin production and support your gut walls, which helps support the gut barrier’s natural function.
  • Communicating with the brain via the gut-brain axis, probiotics may support neurological health and overall wellness. Probiotics support a healthy gut, which may also support overall well-being.1

Top probiotics for digestive wellness

The best probiotics for your digestive wellness will depend on your individual health needs, as well as each strain’s specific effectiveness. Here are some ideas about strains to try:
Common strains, such as Lactobacillus and Bifidobacterium species, work broadly as well. They are adept at supporting your gut barrier and immune responses.

  • Bifidobacterium lactis HN019 is shown to help the growth of healthy bacteria in the gut and support bowel regularity, comfort, and less bloating.
  • Lactobacillus acidophilus NCFM is one of the most well-studied strains of L. acidophilus and is shown to support digestive comfort by helping the body break down food.
  • Lactobacillus casei LC-11 is shown to help balance the gut microbiome.
  • Lactobacillus plantarum LP-115 is shown to support the immune response in the gut.

Choosing the right probiotic supplement

As you search for the right probiotic supplement for your individual needs, it’s important to consider strain-specificity.

The difference between probiotics and prebiotics

Are prebiotics and probiotics the same thing? No, they have different natures and functions. Prebiotics are non-digestible food ingredients (usually certain types of dietary fibers) that act as food for your healthy gut microbiota. They make it through your upper gastrointestinal tract and all the way to your colon intact, where they are fermented by gut microbiota to produce beneficial compounds like short-chain fatty acids (SCFAs).

Probiotics, on the other hand, are live microorganisms that directly add to the population of beneficial microbes in the gut.

Both prebiotics and probiotics play complementary roles in supporting a healthy gut microbiome, working together to aid digestion, immune function, and overall health.

Read more about prebiotics and how to integrate them into your diet.

What are the signs my body needs probiotics?

If you suspect your gut microbiome is out of balance, your body may exhibit these signs, telling you that you could benefit from probiotics.

  • Digestive Issues: digestive discomfort, including bloating, gas, or occasional constipation.
  • Sugar Cravings: An overgrowth of certain yeasts or pathogenic bacteria in the gut might sometimes drive intense cravings for sugar and refined carbohydrates. Probiotics can help balance the gut microbiome, potentially curbing these cravings.

How long do probiotics take to improve gut health?

The time it takes for probiotics to improve gut health can vary from person to person based on the specific probiotic strain you’re taking, the reason for taking it, and the individual’s baseline gut health.
While some people may notice minor changes (like improved bowel movements or less bloating) within a few days to a couple of weeks, it generally takes longer for the beneficial bacteria to have a significant, lasting impact on the gut microbiome. For noticeable and consistent improvements, it often requires several weeks to a few months of consistent daily use.

FAQs about probiotics and digestive health

Q: What are probiotics?
A: Probiotics are live microorganisms that can provide health benefits when taken in proper amounts.

Q: Are probiotics safe to use?
A: Yes, probiotics are generally considered safe for individuals in good health. As always, consult with your health care provider before taking any supplement.

Q: What benefits can I see from probiotics?
A: Probiotics are generally used to support digestive health.

How to take probiotics

Supporting your gut health ultimately comes down to choosing approaches that fit seamlessly into your routine. Probiotics can be incorporated into your daily routine through diet or supplements. Look for foods that are fermented (dairy products like yogurt, kefir, and cheese, non-dairy options such as sauerkraut and kimchi, fermented cereals, pulses, fruits, and beverages like kombucha), which are great sources of probiotics. Supplements like AG1 are also an easy way to make sure you get a consistent daily dose of probiotics. One scoop a day can help fill nutrition gaps and provide the probiotics you need to promote gut health.*

References:

  1. Bagga D, Reichert JL, Koschutnig K, Aigner CS, Holzer P, Koskinen K, et al. Probiotics drive gut microbiome triggering emotional brain signatures. Gut Microbes. 2018;9(6):486-496. doi:10.1080/19490976.2018.1460015.
© 2026 AG1

* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Information on this site is provided for informational purposes only. It is not meant to substitute for medical advice from your physician or other medical professional. You should not use the information contained herein for diagnosing or treating a health problem or disease, or prescribing any medication. Carefully read all product documentation. If you have or suspect that you have a medical problem, promptly contact your regular health care provider.

** AG1 Welcome Kit Offer valid for new AG1 subscribers only. AG1 Pro Welcome Kit included with the first AG1 Pro subscription order only. AGZ Frother Offer valid for first AGZ order only.

According to IQVIA Pro Voice Survey of 248 primary care physicians in December 2025.

††Free shipping on subscription purchases for new U.S. customers only.

  1. In a triple-blind, randomized, placebo-controlled parallel-designed clinical trial evaluating nutrient biomarkers and microbiome shifts in 105 healthy adults ages 20-59 over the course of 12 weeks using the AG1 Next Gen formula.
  2. In a double-blind, randomized, placebo-controlled 2-week crossover clinical trial assessing nutrient gaps and microbiome shifts in 20 active adults ages 19-37 using the AG1 Next Gen formula.
  3. In a double-blind, randomized, placebo-controlled 2-week crossover clinical trial assessing nutrient gaps and microbiome assessments of 40 healthy adults with occasional GI distress ages 26-59 over the course of 4 weeks using the AG1 Next Gen formula.
  4. In a double-blind, randomized, placebo-controlled crossover clinical trial assessing nutrient gaps and bioavailability in 16 healthy adults ages 18-42 over the course of 8 hours using the AG1 Next Gen formula.
  5. In a third-party, single-arm, closed label interventional study of 104 healthy adults ages 25-59 assessing self-perceived efficacy of AG1 Next Gen over 3 months.

ΔTruemed eligibility and approval required. This link will take you to a third party website hosted by Truemed (the "Site"). Linking to this Site does not constitute an endorsement or approval by AG1 or any of its employees of the content, products, services or opinions on the Site. This is being provided as a convenience and AG1 bears no responsibility for the accuracy, legality or content of the Site or for that of any subsequent links on the Site. Contact the owners of the Site for answers to questions regarding its content.

Actual Packaging May Vary

Your privacy is our priority. Learn more: