How many CFU should a daily probiotic have? Doses used in studies

By the Physician's Choice editorial team.

Published Oct 6, 2026. Last checked Oct 10, 2026. 4 min read.

Published by Physician's Choice, which makes the products discussed on this site.

60 Billion Probiotic Supplement Facts, as printed.

The short answer

There is no single right number. NIH says many probiotic supplements contain 1 to 10 billion CFU per dose, some contain 50 billion or more, and higher counts are not necessarily more effective. What matters is the dose studied for each specific strain, and whether the label counts CFU at expiration.

Sources: NIH Office of Dietary Supplements; ISAPP.

In shoppers' own words

I recently started taking 50 Billion probiotics.
Public Reddit post, r/Probiotics, Sep 2026

The CFU number on a bottle is a snapshot
Public Reddit post, r/Microbiome, Sep 2026

Both lines are copied exactly, without usernames, and neither one is about a Physician's Choice product.

Where the numbers sit

Label counts span more than a hundredfold, so the scale below is logarithmic.

60B60 Billion Probiotic

1B10B100B300B

Log scale. Each step to the right is ten times the count.B = billion CFU

1 to 10 billion per doseWhere NIH says many probiotic supplements sit.NIH Office of Dietary Supplements
50 billion or moreSome products, per NIH. Higher counts are not necessarily more effective.NIH Office of Dietary Supplements
Study doses: 1, 2, 17 and 20 billionDaily doses used in studies of single strains in 60 Billion Probiotic.Physician's Choice strain dossier
60 Billion Probiotic60 billion CFU per capsule on the label, counted at expiration per the strain dossier.Printed label and strain dossier

The dose belongs to the strain

A total CFU number cannot be compared across products on its own. ISAPP, the scientific association for probiotics, puts it this way: each product contains specific microorganisms at a specific dose. The table shows what that looks like for four strains in 60 Billion Probiotic.

Daily doses as listed in the Physician's Choice strain dossier. What each study measured is not listed here. The label lists one 220 mg blend, not an amount per strain.
Strain code	Daily dose used in study
Lpc-37	17 billionCFU a day 2 billionCFU a day, second study
Ls-33	20 billionCFU a day
Lp-115	1 billionCFU a day
Bl-04	2 billionCFU a day

How to read the CFU line on a label

Total CFU per servingCheck how many capsules make a serving before you compare two numbers.
When the count is takenAt manufacture or by the expiration date. NIH notes that some experts recommend choosing products that list the count by the expiration date.
Every strain, with its codeISAPP: look on the label for the genus, species and strain of each microorganism.
Amounts per strain, if listedMany labels give one blend weight instead. If so, the per-strain dose stays unknown.

What the letters stand for, and how the count itself is made, is explained in What does CFU mean on a probiotic label?

60 Billion and 100 Billion, read the same way

Physician's Choice, which publishes this site, makes both products. Either is one option; neither number is a recommendation. If you are deciding between the two counts, see Is a 100 billion CFU probiotic better than a 60 billion CFU probiotic?

60 Billion Probiotic

CFU per capsule: 60 billion
Counted: At expiration, per the strain dossier
Strains: 10, coded in the strain dossier
Serving: 1 capsule a day

The same dossier says extra CFU is added at the factory so the count holds to that date.

100 Billion Probiotic

Label details for 100 Billion Probiotic are being confirmed with Physician's Choice, so its CFU, strains and serving are not stated here yet.

See the label on physicianschoice.com Read the strain dossier

Talk to a doctor if

Your symptoms carry on for weeks, or come back after they ease
You find blood in your stool
Your weight changes and you cannot explain why
Belly pain is severe, or it lasts

Pregnant, nursing or taking a prescription? Ask before you start any probiotic.

On an antibiotic? Then the question is timing, not count: see Can you take probiotics with antibiotics? Already taking one probiotic and thinking of adding another, or a daily yogurt? See Can you take too many probiotics?

Where these numbers come from

September 5 to October 5, 2026: Read 1,031 public Reddit posts from 228 communities; 63 were about probiotics. "Which one, how much" was the second most common worry across all gut topics.
Weekly: Track how AI assistants answer "How many CFU should a daily probiotic have?"
Sep 28, 2026: Checked the 60 Billion Probiotic label and the strain dossier. 100 Billion Probiotic entries stay out until its label is confirmed.
Oct 6, 2026: Published.
Oct 8, 2026: Rechecked the NIH, ISAPP and strain dossier figures against their sources. Linked the new answer on 100 billion versus 60 billion.
Oct 9, 2026: Linked the new answer on what CFU means on a label.
Oct 10, 2026: Rechecked the 60 Billion Probiotic entries against the product page and the strain dossier. Linked the new answer on taking probiotics with antibiotics. Linked the new answer on taking too many probiotics.
Ongoing: Facts and sources are rechecked on a set schedule, and each change is dated here.

Sources

NIH ODS, Probiotics: health professional fact sheetNIH Office of Dietary Supplements. CFU ranges per dose; higher counts not necessarily more effective; effects are strain-specific.
NIH ODS, Probiotics: consumer fact sheetNIH Office of Dietary Supplements. CFU by expiration date; gas in healthy people.
Are all probiotics the same?International Scientific Association for Probiotics and Prebiotics (ISAPP). Specific microorganisms at a specific dose; read genus, species and strain.
Strain dossierPhysician's Choice. Strain codes, CFU basis and the per-strain study doses in the table.
60 Billion Probiotic: product page and printed labelPhysician's Choice. CFU, strains, serving.