Choosing The Right Probiotics—What’s a CFU or a Strain?
- Dr. Matt Windham
- Aug 14
- 3 min read
Your body is home to trillions of bacteria—some are helpful, some are not. Probiotics are the good bacteria that help your body stay balanced by supporting digestion, immune function, and even mood health.
What’s a CFU?
CFU stands for Colony Forming Unit. It’s the measurement of how many live and active probiotic organisms are in each dose.
For example: A 20 billion CFU probiotic = 20 billion beneficial bacteria working to support your gut health.
More CFUs aren’t always better—it depends on your unique health needs and the types of strains included.
What’s a Probiotic Strain?
Each probiotic supplement contains different species and strains, and every strain plays a unique role in the body.
Here are a few common strains and what they do:
Lactobacillus rhamnosus GG – Supports gut and immune health
Bifidobacterium lactis – Promotes digestion and regularity
Lactobacillus acidophilus – Supports vaginal and urinary tract health
When choosing a probiotic, the right strains matter just as much as the number of CFUs.
Who Might Benefit from a Probiotic?
You may want to consider a probiotic if you:
✅ Recently took antibiotics
✅ Experience bloating or irregular digestion
✅ Want immune or women’s health support
✅ Are managing stress, travel, or dietary changes
Belew Drugs Probiotic Product Comparison
We carry a wide variety of probiotic formulas for different health goals. Here are some of the top options:
Product Name | CFU Count | Strains | Why You Might Take It |
20 Billion Probiotic | 20 Billion | 9 strains | Daily maintenance of gut flora and immune support |
35 Billion Probiotic | 35 Billion | 8 strains | Balanced daily support for gut and immune health |
100 Billion Probiotic | 100 Billion | 12 strains | High-potency support after illness or antibiotics |
Acidophilus | 500 Million | 2 strains | A starter probiotic for beginners |
Children’s Chewable Acidophilus | 1 Billion | 3 strains | Gentle formula for children’s gut and immune health |
Kids Comfort Probiotic (Organic) | 5 Billion | 14 strains | Digestive and immune support for children |
Mood Formula 50 Billion | 50 Billion | L. helveticus R0052, B. longum R0175 | Supports mood, stress response, and digestion |
Saccharomyces boulardii | 5 Billion | 1 yeast strain | For traveler’s or antibiotic-related diarrhea |
Suprema Dophilus | 5 Billion | 8 strains | Everyday support for digestion and immune health |
Urinary 50 Billion Probiotic | 50 Billion | 8 strains | Supports urinary tract balance, vaginal flora & immune system |
Women’s 50 Billion Probiotic | 50 Billion | Proprietary blend | Helps maintain genitourinary balance & digestion |
Specific Strain Details
Here is a breakdown of the probiotic strains in select products:
Urinary 50 Billion Probiotic: L. acidophilus La-14, L. plantarum Lp-115, L. gasseri Lg-36, L. rhamnosus GG, B. lactis HN019, B. breve Bb-03, B. longum BL-05, L. reuteri 1E1
Women’s 50 Billion Probiotic: L. acidophilus La-14, L. rhamnosus HN001, L. reuteri 1E1, L. gasseri Lg-36, B. lactis HN019
Suprema Dophilus: L. acidophilus La-14, L. rhamnosus HN001, L. casei Lc-11, L. plantarum Lp-115, B. lactis Bl-04, B. breve Bb-03, B. longum BL-05, S. thermophilus ST-21
Mood Formula 50 Billion: L. helveticus R0052, B. longum R0175
Kids Comfort Probiotic: 14-strain blend including L. acidophilus, L. casei, L. rhamnosus, B. infantis, and more
100 Billion Probiotic: 12 strains including L. acidophilus, L. salivarius, L. gasseri, B. longum, B. lactis, and S. thermophilus
Need Help Choosing?
Not all probiotics are created equal—and neither are your health goals. Order online or visit Belew Drugs today and let our pharmacy team help you find the perfect probiotic, tailored to your specific needs in terms of strength, strain, and support. All our formulas are shelf-stable and are backed by science!
This blog post is for informational purposes only and does not substitute for medical advice. Always consult your healthcare provider before starting a new supplement.