Which Probiotic Brands Have Best Scientifically Studied Strains & Species 2021

As more and more probiotics come on to the market, we’ve been paying attention to what specific bacterial strains and species they are using. Why? Well, as more and more research comes out, the more we know about what specific strains do. Now with advertisers claiming probiotics cure everything from IBS to Autism, which of these claims are backed by good science? Let’s find out. You’ve trusted Mamavation to bring you topics like best & worst collagen, best & worst non-toxic cookware, & best & worst air purifiers, now join us as we bring you all the probiotic brands we could find, and which strains hold the most credibility.

Disclosure: This post contains affiliate links. This post has been fact-checked by Rebecca Sherrick Harks RN, BSN.

Mamavation’s Last Probiotic Investigation Unearthed Some Issues in the Probiotic Industry

Last year when we looked at all the most popular probiotic brands, these were most of the striking problems we stumbled across when assessing brands.

• Transparency–Half the brands we studied didn’t cite the specific bacterial strain(s) they were using.
• Consistency & Mislabeling–Study from the University of California found that most brands mislabeled their bacterial strains. We prefer brands that are DNA certified.
• Lacking Resources–Some newer brands are launched by very small teams with little resources, which isn’t so problematic in the food industry, but when it comes to tiny pills, it calls into question whether they have the ability to get quality ingredients and do enough testing.
• Unwilling to Show Labs–Most of the brands we reached out to with questions refused to show us any lab testing.
• Obesogenic Bacterial Strains–Some brands were using some bacterial strains linked to weight gain with study done with Indonesian children.
• Antibiotic Resistance Ties–Some brands were using strains that were linked to antibiotic-resistant bacterial growth.
• Using Us As Lab Rats–Some brands were using bacterial strains that lacked scientific rigor. So we really have no idea what the outcome is going to be. It’s nice that they tell us what they think will happen, but that’s not science.

Different Bacterial Strains Are Linked With Different Health Outcomes

Not all probiotics are created equal. Bacterial strains matter. For example, Lactobacillus rhamnosus is a species, and Lactobacillus rhamnosus SD-LR6-IT is a strain–within each species, there are thousands of strains, and they can each have different functions (or no function at all) in your body. Just like you wouldn’t send a French bulldog to do a sheepdog’s work, you have to be specific about what strains you’re taking.

So let’s break down some of the strongest links to bacteria and probiotics and positive health outcomes.

Bacterial Strains Linked to Strengthening Fertility

Officially these are bacterial strains that can increase natural folate production in the body and improve vaginal health as well as potentially improving fertility through alleviating dysbiosis.

Folate is an essential vitamin that supports cellular health and plays a critical role in fertility and pregnancy. Several bacteria in this group work by helping your body naturally produce more folate. Folate is something you want in preparation for pregnancy–before and through conception. Several other strains lower rates of yeast infections and improve women’s health. The strains listed below perform some of these tasks, but no strain is proven to do them all.  

Bacterial Strains Linked to Digestive Health

Officially these are bacterial strains with strong clinical trials improving digestive health, anti-oxidative stress, GI immunity, and mitochondrial metabolism.

Several probiotic strains have been clinically proven to improve digestive health. These are from the Genera (plural of Genus) Lactobacillus and Bifidobacterium. Strains on the list below perform one or more of the following digestive health activities: health to help maintain regularity, ease bloating, and alleviate occasional constipation. In addition, strains can support gut health helping improve epithelial tight junction formation, thereby supporting gut barrier integrity. Some of these strains also support gastrointestinal immune function, counter oxidative stress, & produce beneficial short-chain fatty acids. A few strains have been shown in vitro to support healthy mitochondrial metabolism and produce urolithin-A. The strains listed below perform some of these tasks, but no strain is proven to do them all. 

Bacterial Strains Improving Metabolism & Energy Production

The ability of the human host to metabolize substances, such as food, is essential for energy and many bodily functions. The bacteria in the intestine play a major role in these activities. The following bacterial strains support better metabolism and increase key metabolites. One particularly important activity is mitophagy–a cellular recycling process that keeps your cells healthy and balanced.

1. Lactobacillus curvatus HY7601 
2. Lactobacillus plantarum KY1032
3. Lactobacillus paracasei CNCM I-4270 
4. Lactobacillus rhamnosus I-3690  
5. Bifidobacterium animalis subsp. lactis CNCM I-2494 
6. Bifidobacterium pseudocatenulatum SPM 1204 
7. Bifidobacterium longum SPM 1205
8. Bifidobacterium longum SPM 1207 
9. Pediococcus pentosaceus LP28
10. Bacteroides uniformis CECT 7771

Bacterial Strains Linked with Improving Cardiovascular Health

The following specific bacterial strains have properties that can promote heart health, such as decrease low-density lipoproteins via bile salts hydrolase activity and improve plasma lipid profiles. A novel important new finding is that some strains (list to be provided) significantly reduce p-cresol sulphate, a compound associated with cardiovascular and chronic kidney disease risk.

Bacterial Strains Linked with Improving Dermatological Health

The following bacterial strains have properties that promote skin health and improve skin clarity and appearance among both children and adults with atopic dermatitis. They reduce inflammation at the surface of the skin.  It is important to note that they work orally, not topically.

Bacterial Strains for Mood Regulation

1. Lactobacillus plantarum PS128
2. Lactobacillus helveticus ROO52
3. Bifidobacterium longum RO175

Spore Based-Probiotics–Some are Safe While Others Are Still Questionable

Spore-based probiotics are all the rage right now because they claim they don’t need special encapsulations to get the bacteria to your gut. (However, this isn’t always true.) But there are some dangers that are being played down by the industry.

The first potential problem is an issue about competition in your gut–should soil-based spores be allowed to compete for space within the gut when they multiply so much quicker than human-based bacteria and can become a problem? Although, some bacterial species like the kind found in fermented soybeans have been found in human intestinal and fecal samples so we can assume they are naturally found. Not all bacterial strains and species would be considered a natural fit for the gut. There are also some other worries about them becoming pathogenic. As we are a precautionary community, I’ll go through the different strains that are popular in the United States so you can see what the science says about each strain:

• Bacillus subtilis—these bacteria produce an enzyme that can degrade oxalate and is found naturally in natto, traditional Japanese food made from fermented soybeans. These four strains have been studied extensively, but not others.
  •  Bacillus subtilis DE111
  •  Bacillus subtilis CU1 (“LifeinU”)
  •  Bacillus subtilis R0179
  •  Bacillus subtilis IP 5832
• Bacillus indicus–Bacillus indicus has been touted for its ability to potently stimulate the immune system, but we know very little about its safety or effectiveness in humans. A few brands we found use these strains.
• Bacillus coagulans—The most clinically studied spore species,  which produces L-lactic acid. These three spore strains below are helpful for people with IBS. Other ones are not proven safe or effective in humans.
  • Bacillus coagulans GBI-30, 6086 (“Ganeden BC30”)
  • Bacillus coagulans Unique IS-2 (“ProDURA”)
  • Bacillus coagulans MTCC 5856 (“LactoSpore”)
• Bacillus licheniformis—Of all soil-based species used in probiotics, B. licheniformis is perhaps the most controversial because it may be an opportunistic pathogen and can cause infection in immunocompromised individuals. 
• Enterococcus faecium—this bacteria is a normal resident of your gut, however, it can also be pathogenic, causing disease. Many strains have developed antibiotic resistance. Therefore, there are concerns about its use as a probiotic.
  • Enterococcus faecium M-74
  •  Enterococcus faecium L3
  •  Enterococcus faecium IS 27526
  •  Enterococcus faecium WB 2000
  • Enterococcus faecium CRL 183

Seed’s Daily Synbiotic DS-01 Qualifies for IND Study In Persons with IBS

Seed’s Daily Synbiotic is the only multi-strain commercially available probiotic brand to receive authorization from the Food and  Drug Administration (FDA) as an IND (investigational new drug), to study the effects of DS-01 (Daily Synbiotic) on patients living with IBS (irritable bowel syndrome).

An IND is an important research milestone because it grants permission for a company to begin clinical trials in the US to investigate the safety and tolerability of a drug, food, or dietary supplement among persons with a chronic condition or disease.

The only other commercially available brand that was approved for an IND at the FDA is Culturelle. However, they only have a single strain product and we don’t like the junk and fillers they use in their product.

And why is this a really big deal? Well, an IND is required to study a product in the United States. Another important part is that Irritable Bowel Syndrome (IBS) has an incredibly high placebo effect, meaning that when people THINK they are getting treatment, they tend to get better. One study found “the placebo response ranged from 16.0 to 71.4% with a population-weighted average of 40.2%.”

So if the placebo effect can take place up to 40% of the time, how can you tell from all the marketing what type of probiotic is REALLY working on IBS? This is why studying up on the strains and research behind their effectiveness is so important. It’s estimated that IBS sufferers comprise of 11% of the world’s population.

Featured Probiotic Brand to Try–Seed Daily Synbiotic DS-01

Take a look at our favorite probiotic–Seed Daily Synbiotic DS-01! Seed’s probiotic is a synbiotic, combining 24 DNA verified human-based probiotic bacterial strains with a prebiotic, protected in a dual-staged capsule. It’s also biofermented in Europe and free of all 14 allergen classes as defined by  the European Food Safety Authority (EFSA).

Seed’s Daily Synbiotic includes 24 DNA-verified bacterial strains that are linked to the following health benefits:

• digestive health
• heart health
• skin health
• gut immune function
• cardiovascular health
• gut barrier integrity
• increases folate production from within the body, which is great for pregnancy!

Seed Daily Synbiotic is also a plastic-free lover’s dream. Their packaging is compostable, and nothing they ship you will harm the environment, in fact, it all safely goes back into the Earth.

DISCOUNT: 20% off first month’s order of Seed Daily Synbiotic

Discover Seed’s Daily Synbiotic here. If you would like to test them out, you can sign up for a monthly membership and delivery for $49.99 per month. (The first month is 20% off when you use discount code “MAMAVATION“.)

Click here to get 20% off your first month and use tell us how it goes!

Mamavation’s Investigation of Probiotic Brands & Best Supported Bacterial Strains

Many probiotic brands use bacterial species and strains that lack clinical evidence, make unsubstantiated statements, and cite highly questionable “research”. We also combined that with the ingredient quality, encapsulations used, and desire to follow the rules.

Not My Favorite Probiotic Brands

These brands either didn’t contain any bacterial strains that were closely linked with health impacts we set forth above OR they did not tell us what bacterial strains they were using at all. This is important for transparency, safety, and effectiveness. Brands in this area may also contain additives and junk we just don’t want in our probiotics.

• Advocare ProBiotic RESTORE™ ULTRA
• Bioptimizers P3-OM Probiotics
• Biospora (Klaire Labs)
• Country Life Probiotic Daily Powder
• CVS Health Maximum Strength Probiotic
• DNA Miracles- for babies–NutraMetrix DNA Miracles® Probiotics Extra
• doTERRA DigestZen PB Assist+
• Dr. Axe (SBO) Probiotics
• Garden of Life Primal Defense Capsules
• Garden of Life Raw Probiotics™ Ultimate Care
• Good Health Naturally
• JayLabPro Probiotics
• Mary Ruth’s Organic Liquid Probiotic
• Neora Prolistic™ Pre & Probiotic Plus Vitamins
• Nutrition Now PB8 Acidophilus
• Plexus ProBio 5
• Primal Probiotics
• Probiotic 3
• PRO-Moms Time Released, Designed for Expecting & Nursing Women
• Renew Life Daily Balance Probiotics & Organic Prebiotics

Better Probiotic Brands

These brands made the middle of the road. Some of these brands I love the research on but they contain junk, while other brands are the opposite–they contain great ingredients, but the bacterial strains they are using are not proven safe and effective yet. We scrutinized SBO based brands a bit more because of their newness. Some SBO bacterial strains are so new that we are effectively lab rats when consuming them.

• Accuflora Probiotic Supplement
• Align Probiotic
• Amare Global Probiotics
• Bio-K+ Probiotic Supplement Capsule (25 billion)
• Bio-Kult Original (UK Version)
• Culturelle Digestive Health Daily Probiotic Capsules
• Custom Probiotics Adult Formula CP-1
• Designs for Health Probiotic Synergy
• Dr. MK–Teen/Adult Probiotics Chewable by Doctor MK’s
• Dr. Mercola Complete Probiotics 70billion CFU
• Dr. Ohhira’s Probiotics Professional Formula
• Flora Adult’s Probiotic
• Florajen Women’s Probiotics
• Holistic Blends Super Shield Probiotics
• Hyperbiotics Pro-15
• Isagenix – IsaBiome™ Probiotics
• Jarro-Dophilus EPS®
• Just Thrive
• Klaire Labs Ther-Biotic Complete
• Lifeway Kefir Probugs
• MegaSporeBiotic
• Metagenics UltraFlora Control
• MegaFood MegaFlora Women’s Probiotic
• New Chapter Probiotic all-flora™
• Natren Healthy Trinity Probiotic
• Organic3 GutPro Probiotic
• Phillips Colon Health Probiotic Capsules
• ProFlora 4R
• Pure Encapsulations Probiotic 50B
• Regular Girl Original Powder
• RightBiotics Rx
• Thorne FloraMend Prime Probiotic
• Visbiome Extra Strength High Potency Probiotic

Best Probiotic Brands

These brands are using strains of bacteria that have proven to be safe and effective. These brands also contain no fillers and junk inside their formulation (except for one gummy that we included for you) and you can expect the bacteria getting to the gut based on their encapsulation technology or the fact that they are made from a safe & effective SBO. We have included one brand here that is a gummy for people who have trouble swallowing pills. This gummy has some natural flavors, but we suspect the bacterial strains work fine.

• Seed Daily Synbiotic DS-01–Qualified for an IND study with the FDA and if passed will be able to make drug claims on this product for IBS. Uses 24 bacterial strains with very reputable science behind safety and effectiveness in digestive health, heart health, skin health, gut immunity, gut barrier integrity, and micronutrient synthesis. Contains: Bifidobacterium longum SD-BB536-JP, Bifidobacterium breve SD-BR3-IT, Lactobacillus plantarum SD-LP1-IT, Lactobacillus rhamnosus SD-LR6-IT, Lactobacillus reuteri SD-LRE2-IT, Bifidobacterium longum HRVD90b-US, Bifidobacterium lactis RD-BS5-IT, Lactobacillus casei HRVD300-US, Bifidobacterium breve HRVD521-US, Bifidobacterium lactis HRVD524-US, Lactobacillus rhamnosus HRVD113-US, Bifidobacterium lactis SD-150-BE, Lactobacillus rhamnosus SD-GG-BE, Lactobacillus reuteri SD-RD830-FR, Bifidobacterium adolescentis SD-BA5-IT, Lactobacillus crispatus SD-LCR01-IT, Lactobacillus fermentum SD-LF8-IT, Lactobacillus plantarum SD-LPLDL-UK, Bifidobacterium lactis SD-MB2409-IT, Lactobacillus salivarius SD-LS1-IT, Bifidobacterium lactis SD-CECT8145-SP, Bifidobacterium longum SD-CECT7347-SP, Lactobacillus casei SD-CECT9104-SP. Use “MAMAVATION” at checkout for 20% first month’s order. 
• SmartyPants Probiotic (Adult gummies only)–Spore-based organisms, using strain Bacillus subtilis DE111 & Bacillus coagulans MTCC 5856 (“LactoSpore”) that have been studied extensively and are safe and effective in adults. (This is the only gummy version we pulled in here so it has sugar and corn syrup and some natural flavors, but this is a good selection if pills give you a gag reaction.)
• Now Foods Probiotic-10™ 100 Billion Veg Capsules–Contains: Lactobacillus acidophilus (La-14), Bifidobacterium lactis (Bi-04),Lactobacillus plantarum (Lp-115), Lactobacillus casei (Lc-11), Lactobacillus rhamnosus (Lr-32), Lactobacillus paracasei (Lpc-37), Bifidobacterium breve (Bb-03), Streptococcus thermophilus (St-21), Lactobacillus salivarius (Ls-33), Bifidobacterium longum (Bi-05)
• Purium Biome Medic–Contains: Contains Bacillus coagulans MTCC 5856 (“Lactospore”) that has been studied extensively and is safe and effective in adults.

About the Author

Leah Segedie is a consumer watchdog, author, entrepreneur, environmental activist, and mother of three boys. 

She wrote Green Enough: Eat Better, Live Cleaner, & Be Happier (All Without Driving Your Family Crazy!) in 2018. She’s consistently been featured in the media for the past 15 years in media outlets like ABC, CBS, CNN, Yahoo, Chicago Tribune, USA Today, Reader’s Digest, Ladies Home Journal, Shape Magazine, Fitness Magazine to name a few.  

Follow Mamavation on Pinterest, Facebook, Instagram, or Twitter or join the Mamavation Community Group. 

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