BUYING GUIDE35,000/month searches
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Not FDA evaluated

Before You Buy Probiotics

What to look for (and what to avoid)

TL;DR

Match strains to your goal (Lactobacillus for digestion, Bifidobacterium for immune). 10-30 billion CFU is plenty. Shelf-stable strains are fine. Strain matters more than CFU count.

Quick Checklist

Lists specific strains (e.g., L. rhamnosus GG)MUST HAVE
CFU count guaranteed at expiration, not manufactureMUST HAVE
10-30 billion CFU (more ≠ better)IMPORTANT
Shelf-stable or properly storedIMPORTANT
Clinical research on specific strainsNICE TO HAVE

What to Look For

Red Flags (Avoid)
"100 billion CFU!"

Marketing. 10-30B works fine. More can cause bloating.

Only lists species, not strains

L. acidophilus is useless info. Which STRAIN matters.

"Proprietary probiotic blend"

Hiding what you're actually getting.

CFU at time of manufacture

Half could be dead by the time you take it.

Requires refrigeration but shipped unrefrigerated

Dead probiotics don't work.

Green Flags (Look For)
Strain-specific listing (numbers after species)

Shows they know what they're doing.

"CFU at expiration" guarantee

What you see is what you get.

Clinically studied strains

Actual research, not guesswork.

Acid-resistant capsule or technology

More survive stomach acid.

Forms Ranked

FormScoreBest ForNotes
Shelf-stable capsules
9/10
Convenience, travelModern strains don't need refrigeration
Refrigerated capsules
9/10
Some strainsNecessary for certain sensitive strains
Spore-based
8/10
Gut repairBacillus strains, very stable
Powder
7/10
Mixing in drinksFlexible dosing
Gummies
5/10
Kids, taste preferencesLower CFU, sugar content

Dosing Guide

Minimum1-5 billion CFU
Optimal10-30 billion CFU
MaximumVaries by strain
When to TakeWith or without food (varies by strain)
Pro TipSome strains work better with food, some without. Check specific strain research.

Is Probiotics For You?

You Might Need It If...

  • After antibiotic use (rebuilding gut)
  • People with IBS or digestive issues
  • Those with frequent infections
  • Anyone wanting immune support
  • People on processed food diets

You Probably Don't Need It If...

  • People eating fermented foods daily (yogurt, kimchi)
  • Those with compromised immune systems (SIBO, etc)
  • Anyone doing fine without them

Common Mistakes

Reality:

Strain matters more. 10B of the right strain beats 100B of random ones.

The Bottom Line

Match strains to your goals. 10-30 billion CFU is enough. Specific strain names (with numbers) = quality product. CFU at expiration, not manufacture. Strain selection matters more than anything.

Learn More About Probiotics

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About this information: Our analysis of Probiotics is based on peer-reviewed research from PubMed, ClinicalTrials.gov, and NIH databases. These statements have not been evaluated by the FDA. Supplements are not intended to diagnose, treat, cure, or prevent any disease.

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