Here Are the Top 14 Nutritionist-Approved Prebiotics and Probiotics on the Market

Culturelle probiotics are audited by the National Sanitation Foundation (NSF), a reputable third-party testing company that certifies a supplement’s quality and safety. They are produced in compliance with U.S. Food and Drug Administration current good manufacturing practices (CGMP), which ensure that the highest quality control measures are met. Culturelle capsules are packaged with a desiccant (a drying agent that can be made of materials like silica gel or calcium oxide) lining to absorb moisture and protect the viability of the live bacteria.

We particularly appreciate that the company shares research on the strains present in the product. You can find studies on each ingredient and its potential benefits on the website. This product is rigorously monitored for over 20 allergens, including common food allergies in kids, such as nuts, dairy, soy, gluten, and sesame. However, it’s not labeled as allergen-free, so check with the manufacturer if the child has a food allergy. While it’s not third-party tested, Seed independently tests each batch for potency, heavy metals, pesticides, allergens, and overall stability.

Fencl underlines the importance of ensuring that you get a safe, reputable, and effective supplement. All Klean products are NSF Certified for Sport, signifying strict standards for safety, quality, and regulatory measures. This mark also provides peace of mind that there are no banned athletic substances in the product.

SFI Health (formerly Klaire Labs) uses third-party testing to ensure safety and potency. We value the transparency of its product research, with several studies linked under the website's FAQs section. Not all companies do this, adding to SFI's trustworthiness and the proof of effectiveness of its products.

Note that some customers reported receiving either an empty box or a smaller amount than ordered, so check deliveries upon receipt. The company has a 30-day money-back return policy for any reason.

This easy-to-swallow capsule has little to no aftertaste, so you can take it and move about with your day. While this product contains clinically tested ingredients, there’s no evidence that the company conducts third-party testing to ensure the viability of these ingredients. In addition, a few users reported that they received unsealed bottles. If this happens, contact customer service via the website to request a replacement.

If you’re looking for a budget-friendly supplement, Swanson Dr. Stephen Langer's Ultimate 16 Strain Probiotic With FOS is our top pick: It costs around $7.99 per month if you purchase a 120-day supply on the company's website. If you’re on a tight budget, this prebiotic and probiotic is the most affordable on our list, and it contains research-studied ingredients. Swanson has been in business for over 50 years. “Swanson is a well-established supplement brand,” says Ana Reisdorf, RD, founder of GLP-1 Hub in Franklin, Tennessee.

Swanson conducts regular in-house testing and third-party testing on all of its products, and requires a certificate of analysis from every supplier to ensure that the ingredients meet the highest expectations of quality. Swanson offers a 100-day money-back guarantee if you’re unhappy with the product.

The capsule is very small and easy to swallow, which can be helpful if you already take a lot of pills or often need a lot of water to get pills down. Some users received bottles that had expired or would shortly after delivery. While rare, a few customers reported headaches after taking the product.

Naked Nutrition's Naked Gut contains a potent formula of several prebiotics and probiotics, along with glutamine and licorice root, for daily digestive support. It’s vegan, soy-free, and gluten-free. Naked Nutrition is known for its commitment to clean, transparent labeling and high-quality ingredients — many of its products are free of artificial colors, flavors, preservatives, and fillers.

Naked Gut delivers a potent combination of four prebiotic fibers:

• 2,000 milligrams (mg) acacia
• 1,000 mg citrus pectin
• 1,000 mg xylooligosaccharides (IXOS)
• 850 mg inulin (from Jerusalem artichokes)

Naked Gut is third-party tested and produced in a CGMP-certified facility. While a powder prebiotic can be convenient, our research found that Naked Gut powder could sometimes be very hard and clumpy, making it difficult to scoop. If this happens, contact the manufacturer, as it offers a 14-day free return policy.

“Research shows that a balanced gut microflora plays a significant role in supporting immune function,” she says. “Incorporating a high-quality supplement like Douglas Laboratories Multi-Probiotic 40 Billion is a top choice due to its 16 strains of probiotics with prebiotics, creating a synbiotic effect that helps establish a healthier gut environment.”

Douglas Laboratories has been in business for 65 years and conducts regular in-house testing. Its products are CGMP certified.

If taking an arsenal of supplements every day is overwhelming, you may prefer an all-in-one prebiotic, probiotic, and multivitamin supplement. Athletic Greens (AG1) combines a greens powder, multivitamin, prebiotic, and probiotic blend into a single scoop of powder. Greens powders are a dietary supplement that can help boost your daily intake of vegetables, vitamins, and minerals — but not all of them also contain probiotics, as this AG1 version does.

AG1 is NSF Certified for Sport, one of the most reputable third-party testing designations for ingredient purity, lack of heavy metals, and pesticides. This certification also ensures that the product is tested for substances banned in athletic competitions.

Our research found that some people may not like the taste, so mixing it into a smoothie or a flavored protein shake may be better than plain water. Some customers reported not receiving a scoop with their purchase and found it difficult to get a hold of customer service.

Ritual products are third-party tested, and the company has a scientific advisory board of medical doctors, registered dietitians, and scientists that performs ongoing research to further ensure the optimal safety, quality, and effectiveness of the products. Ritual values transparency, and the ingredients in its synbiotic are listed on a Traceable Ingredients page on the company's website. The trifecta of pro-, pre-, and postbiotics help make Ritual’s Synbiotic+ a well-rounded option to include in a consistent health routine.