01Probiotics vs Prebiotics vs Postbiotics
| Term | What It Is | Example |
|---|---|---|
| Probiotic | Live beneficial microorganisms | Lactobacillus acidophilus, Bifidobacterium lactis capsules |
| Prebiotic | Fiber that feeds beneficial gut bacteria | Inulin, fructooligosaccharides (FOS), acacia fiber |
| Postbiotic | Beneficial compounds produced by bacteria | Short-chain fatty acids like butyrate (newer category) |
| Synbiotic | Probiotic + prebiotic combined | A capsule pairing strains with inulin or FOS |
02CFUs: What the Billion Count Really Means
CFU stands for colony-forming units — the number of live organisms per serving at time of manufacture. Here's what the numbers don't tell you: higher isn't automatically better. Probiotic effects are strain-specific, meaning a well-studied strain at 10 billion CFU can outperform an unstudied blend at 100 billion. Use CFU as a rough potency signal within a brand you trust, not as the deciding factor between products. Also check whether the count is guaranteed "through expiration" (better) or only "at time of manufacture" (the number declines on the shelf).
03The Strains That Matter Most
Genus, species, strain — e.g., Lactobacillus acidophilus La-14. That strain code at the end is what the research actually studied, so products listing full strain designations are a quality signal. The most established groups:
- Lactobacillus (now partly reclassified to Lacticaseibacillus etc.) — the workhorse genus; common strains include L. acidophilus and Lacticaseibacillus rhamnosus GG, one of the most studied strains in existence.
- Bifidobacterium — dominant in the colon; B. lactis BB-12 is another heavily researched strain.
- Saccharomyces boulardii — technically a yeast, not a bacterium; the probiotic strain with the most research behind it for digestive upset during antibiotic use and travel.
04Refrigerated vs Shelf-Stable
Refrigeration was once a quality marker, but modern freeze-drying and packaging have made shelf-stable probiotics reliable — provided the brand guarantees CFU through expiration and uses moisture-barrier packaging. Either format works. What matters more: buy from brands that publish strain designations and third-party testing, and don't buy more than you'll use before expiry.
05Prebiotics: Feeding the Good Guys
Prebiotics are fibers — inulin, FOS, galactooligosaccharides (GOS), acacia fiber, partially hydrolyzed guar gum — that pass undigested to the colon where beneficial bacteria ferment them. You can get them from food (onions, garlic, asparagus, bananas, oats) or as standalone powders. Fair warning: they commonly cause gas and bloating at first. Start with a small dose and increase gradually — your gut adapts over a couple of weeks.
Frequently Asked Questions
How many billion CFU probiotic should I take?
There's no universal right number — effects are strain-specific, not dose-proportional. A 10–25 billion CFU product with well-studied, fully named strains is a sensible daily range for most people. Very high counts (100B+) are typically for short-term targeted use. More important than the number: named strains and a through-expiration guarantee.
What's the difference between probiotics and prebiotics?
Probiotics are the live beneficial organisms themselves; prebiotics are the fibers that feed them. Think seeds vs fertilizer. Many people benefit from both, and synbiotic products combine them — though you can also just eat more fiber-rich foods.
Should probiotics be refrigerated?
Not necessarily anymore. Shelf-stable formulas with proper packaging and a through-expiration CFU guarantee are reliable. Refrigerated products are fine too — just don't assume refrigeration alone means higher quality.
When should I take probiotics — with food or on an empty stomach?
Evidence is mixed; many manufacturers recommend with food (the meal buffers stomach acid), and that's a reasonable default. Consistency matters more than timing — pick a routine you'll stick with.
Can probiotics cause side effects?
Mild gas and bloating in the first week or two is common as your gut adjusts — it usually passes. People with compromised immune systems or serious illness should talk to a doctor first, since live organisms carry small risks in those cases.
Where can I buy probiotics and prebiotics in Richmond, CA?
William's Natural Foods at 12249 San Pablo Ave, Richmond, CA 94805 carries probiotics from 10 to 100+ billion CFU, refrigerated and shelf-stable, plus prebiotic fibers and synbiotic formulas. Open Monday–Friday 9 AM–7 PM, Saturday 9 AM–6 PM, Sunday 10 AM–5 PM. Call (510) 232-1911 to check what's on the shelf.
Still Have Questions? Come Talk to Us In Store
The fastest way to get answers is to talk it through in person. Here's how:
This article is for informational purposes only and is not medical advice. If you have a compromised immune system, are seriously ill, or take immunosuppressants, talk to your healthcare provider before using probiotics. These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.