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These 4 best over the counter probiotic supplements are made up of multiple strains of essential bacteria in a dosage good enough to provide you with results.
We made research on the ingredient of the popular probiotics from major supplement shops and found the best for a variety of common problems.
How We Chose the Best Probiotic Supplements
The search for the best probiotics started with the most popular products from major supplement online shops like Amazon, Drugstore.com, GNC, and Whole Foods. That resulted in over 200 supplements. With so many options, we then narrowed our search to 70 probiotics whose purity, potency and efficacy were vetted by an independent lab like ConsumerLab, Labdoor and National Science Foundation (NSF). Those labs test — in other words — supplements’ actual composition against labels, acknowledging that ingredient lists are trustful and that they have no contaminants. Because supplement claims aren’t regulated by the Food and Drug Administration (FDA), we wanted to make sure someone was testing whether they worked as described.
CFUs — colony forming units — is the amount of active live organisms inside the bacteria. As per ConsumerLab, “a probiotic should have at least 1 billion CFUs … with doses actually start from 1 billion and 10 billion CFUs daily for adults.”
That said, supplements with higher numbers of CFUs are sometimes used to treat conditions such as irritable bowel syndrome (IBS), allergies, and respiratory illness. While probiotics have generally been found to be safe for most people with normal immune systems, too much can cause gas and upset stomach. We narrowed our search for the best probiotics to supplements with dosages between 1 billion and 100 billion CFUs.
Multiple strains of bacteria
Research suggests probiotics work better as a team. Even pairs are more effective than individuals. If you look at the strains Lactobacillus Acidophilus and Bifidobacterium Bifidum BB-12, for example. The combination of this duo-force has been shown to help treat GI-specific ailments. In fact, one survey found 75 percent of studies that compared the effect of a strain mixture with a single-strain supplement showed a mixture was more effective at improving irritable bowel symptoms, immune function, and digestive health.
Selecting a multi-strain probiotic is also in line with the theory that filling your stomach with enough good bacteria out-competes the bad bacteria for the same space and resources. In your gut, the more diversified the good bacteria, the harder it is for the baddies to gain a foothold. With all this in mind, we only looked at supplements containing multiple strains of bacteria.
In addition, we wanted supplements with bacteria strains that have the most evidence of being truly effective. We dug through probiotic studies from the National Center for Biotechnology Information, dissected ConsumerLab’s extensive report, and verified those findings with our experts.
We found the most evidence linking strains to antibiotic recovery, immune health, and IBS/IBD relief. We made checklists of the most researched strains that treat those issues (10 strains famous for boosting general health, six are for immune health, seven for antibiotic recovery, and seven for IBS/IBD relief) and dug into ingredient lists to find the supplements containing the highest number of effective strains for each use case.
We also found strains linked to five other health benefits like weight loss and lowering cholesterol. We feature options for those cases below, but they aren’t top picks because those use cases aren’t as heavily researched as immune health or IBS relief. Still, chances are any probiotic supplement is going to make some improvement to your digestive health, so don’t be afraid to experiment.
Bacteria reduce in number over time. Some supplements list the potency when they were manufactured (before they rode in a truck, sat on the shelf at the grocery store, or hung out in the kitchen cupboard for a few months). In this case, there could be dramatically fewer viable bacteria by the time you used them than when they were first encapsulated, and good bacteria are no good to you when they are dead.
The best probiotic producer will list their potency (in CFUs) at the time of expiration, making sure that you get the dosage you’re paying for. Dr. David Perlmutter, board-certified neurologist, American College of Nutrition Fellow, and author of The New York Times bestsellers “Brain Maker” and “Grain Brain” puts it this way: “Avoid products that indicate a specific number of bacteria ‘at the time of manufacture,’ and instead look for products that, like other supplements, have a shelf life.” Each of our top picks clearly shows a specific “best by” or “expires on” date on its bottle.
4 best over the counter probiotic supplements
- Vita Miracle Ultra-30 Probiotics-Best for General Digestive Health
- Renew Life Ultimate Flora Extra Care 30 Billion-Best for Immune Health
- MegaFood MegaFlora-Best for Antibiotic Recovery
- Formulas Nexabiotic Advanced Multi-Probiotic-Best for IBS/IBD Relief
- Formulas Nexabiotic Advanced Multi-Probiotic-Best for General Digestive Health Vita Miracle
This tiny capsule contains nine of the 10 strains recommended for general gut health.
Why we chose it
The right strains to promote gut health
If you don’t have a specific health goal in mind and want to bolster the number of good bacteria floating around your system, Perlmutter recommends starting with a minimum of eight to 10 different bacterial species. He included a core five (L. Plantarum, L. Acidophilus, L. Brevis, B. Lactis, and B. Longum) and we added five more highly researched and universally beneficial strains for a general health pick. Vita Miracle, formerly Islands Miracle, has nine of those 10, plus 30 billion CFUs per serving.
Gluten-free and dairy-free
Because the supplements don’t contain gluten or dairy, they’ll be easy on your stomach. That’s a win if you already have a sensitive digestive system.
Points to consider
Two capsules per serving
Most of the probiotics on our list only require one supplement per serving. If you don’t like swallowing pills, two might feel like an inconvenience.
When we opened the bottle, we noticed a slightly sour smell — common with nearly all the probiotics we tested. It’s subtle, but if you’re particularly sensitive to smell or are wary of stinking up your supplement cupboard, it’s worth considering.
This option uses bacteria that can improve upper respiratory infections and aid in the treatment of autoimmune disorders.
Why we chose it
The right strains to improve immune function
In addition to the prophylactic effect of filling your gut with good bacteria, there are some probiotic strains proved in treating symptoms of autoimmune disorders, including L. Paracasei and L. Acidophilus. Others, like B. Lactis, could help fight against respiratory infections. Renew Life Flora Extra Care includes all three targeted bacteria strains at 30 billion CFUs per serving.
Highly accurate labeling
All the best probiotic we picked received high scores from Labdoor, however, Renew Life earned the highest label accuracy score out of all the picks: 78.6 out of 100. This means chances are good you’ll get the bacteria and CFUs the product is advertising — a difficult feat for sensitive bacteria that die off over time.
Points to consider
The capsules are a bit larger than the penny-size Vita Miracle probiotic, which might be a dealbreaker if you have trouble swallowing pills. If it’s any consolation, though, you only need to take one of the larger pills per day.
It’s worth noting that, like MegaFood MegaFlora, the Renew Life label recommends cold storage — which creates a little more work for you in remembering to take your probiotic.
Unlike MegaFood, the Renew Life label’s cold-storage recommendation is printed so small we nearly missed it (and it didn’t ship with a cold pack). If a probiotic requires refrigeration, be vigilant when buying it — the retailer that stores it or the company that ships it should keep it refrigerated until it gets to you. Otherwise, some of its potency might diminish in storage or transit.
This supplement fills your digestive tract with good bacteria until it’s fully removed from an antibiotic course. In addition, it is vegan.
Why we chose it
The right strains to revamp your microbiome
Antibiotics wreak havoc on your microbiome by decimating both good and bad bacteria. It’s an effective treatment if you have an infection, but without the gut good guys, you could come out on the other side of any antibiotic treatment with a weaker immune system.
Taking relatively high doses of these probiotic strains before, during, and after antibiotic treatment can help your microbiome get back on its feet: B. Lactis, B. Infantis, L. Acidophilus, L. Casei, L. Bulgaricus, L. Paracasei, L. Rhamnosus GG, and S. Boulardii. Our antibiotic combatant MegaFood MegaFlora includes six of these strains, as well as eight others. One serving contains 20 billion CFUs to feed the good bacteria.
MegaFood is our only top pick that’s certified vegan, as well as being gluten-free and dairy-free, making it a good choice for any food-allergic or vegan probiotic seeker. It has fewer of our wishlist “general health” strains than Vita Miracle, but it still contains five. This could be a go-to if you eat vegan, even if you’re not recovering post-antibiotic.
The capsules are about the length of a dime. While these are easy to drop or misplace, they’re also perfect if you have trouble swallowing pills. What’s more, you only have to take one per day.
Points to consider
To sustain the life of the CFUs, it’s imperative you keep this supplement in the fridge. The label indicates it should be stored cold, and it was even shipped to us with an ice pack. If you typically store pills in a pillbox or on the counter, this might make it harder to remember to take your supplement.
Research suggests that the bacteria in Dr. Formulas can ease the symptoms of irritable bowel syndrome and acute infectious diarrhea.
Why we chose it
The right strains to improve IBS and IBD symptoms
There has been a lot of research on treating IBS and IBD symptoms with probiotics — much more than on most other pathologies. There are many strains proved to alleviate symptoms — L. Acidophilus and E. Faecium came up again and again in our research.
Dr. Formulas Nexabiotic Advanced Multi-Probiotic contains both of these and five other relevant species (with 23 strains total) in its 34.5 billion CFU serving.
High Labdoor scores
This product has the highest overall Labdoor score of our picks at 92.4 out of 100 and the highest score in its “projected efficacy” category at 100 out of 100 — a score “based on a product’s active ingredients, their levels, and their specific biochemical properties.” While all of our picks boast strong scores, a 100 out of 100 is a rare gem.
Points to consider
Although you only have to take one supplement per day, the capsule itself isn’t as small as those from MegaFood. This might be an issue if you have trouble swallowing pills.
Guide to probiotic supplements
How to choose the right probiotic supplement for you
Get familiar with bacteria strains
Dr. Michelle Schoffro Cook says there’s no single best strain of bacteria, though some strains, like L. Acidophilus or B. Bacterium, consists of wide-reaching effects. They often act as a starting point from which to add other strains with more specific impacts. Already have probiotics on hand or want to arm yourself with raw knowledge before you shop? The table below shows the research- and expert-backed strains we looked for in each use case:
|Beneficial Strains||Our Top Picks|
|General Digestive Health||L. Plantarum|
|Vita Miracle Ultra-30 Probiotics|
|Antibiotic Recovery||S. Boulardii|
|Immune Health||L. Plantarum|
|Renew Life Ultimate Flora Extra Care 30 Billion|
|IBS/IBD Relief||B. Infantis|
|Dr. Formulas Nexabiotic Advanced Multi-Probiotic|
Know of the issue you’re after
Our top picks are packed with strains for the most research-supported use cases. While sorting through the most popular probiotics on the market, though, we also found supplements with strains for other, less-researched common use cases:
- 21st Century Ultra Potency Advanced Probiotic-Best for Anxiety and Allergies
- Nature’s Way Primadophilus Fortify Women’s Probiotic-Best for Weight Loss
- Advocare Probiotic Restore Ultra-Best for Lactose Intolerance
- Garden of Life Dr. Formulated Probiotics Once Daily Women’s-Best for Lowering Cholesterol
- Hyperbiotics PRO-15 Advanced Strength-Best for Women’s Health
- NOW Foods Probiotic-10-Another Vegan Option
Probiotic Supplements FAQ
The Best Probiotic Supplements: Summed Up
|Vita Miracle Ultra-30 Probiotics||Renew Life Ultimate Flora Extra Care 30 Billion||MegaFood MegaFlora||Dr. Formulas Nexabiotic Advanced Multi-Probiotic|
|The Best for General Digestive Health||The Best for Immune Health||The Best for Antibiotic Recovery||The Best for IBS/IBD Relief|
|Price (on Amazon)||$28||$14||$45||$15|
|Supplements per bottle||60||30||90||30|
|Supplements per serving||2||1||1||1|
|Number of strains||18||12||14||23|
|CFUs per serving||30 billion||30 billion||20 billion||34.5 billion|
|Labdoor Overall Score (out of 100)||70.5||78.6||77.2||92.4|