Probiotic vs Prebiotic: What's the Difference, and Do You Need Both?

Quick answer: Probiotics are the live beneficial bacteria themselves. Prebiotics are the fibre that feeds those bacteria. Probiotics restock your gut; prebiotics keep your existing good bacteria thriving. For most people, taking both — either separately or in a single synbiotic product — is the most effective strategy for long-term gut health.

If you've ever stood in front of the probiotic shelf wondering why some bottles say "with prebiotic," why others need to be refrigerated, and why one costs $25 and another $80 — this guide will sort it out in plain language.

Let's get into it.

Why Your Gut Microbiome Matters

Your gut is home to roughly 38 trillion microbes — more cells than the rest of your body combined. This community (your microbiome) does some heavy lifting:

Breaks down fibre your stomach can't digest
Produces vitamins like K2, B12, folate, and biotin
Trains and regulates 70% of your immune system
Makes neurotransmitters (about 90% of your serotonin is produced in the gut)
Controls inflammation, mood, skin clarity, and even sleep quality

Modern life is rough on this community. Antibiotics, stress, low-fibre diets, alcohol, chlorinated water, and ultra-processed food all knock the good bacteria down and let the troublemakers take over. Signs your microbiome may be out of balance:

Bloating, gas, or unpredictable bowel movements
Brain fog or low mood
Frequent colds
Skin breakouts, eczema, or rosacea flares
Sugar cravings
Recovering slowly from antibiotics

This is where probiotics and prebiotics come in — and understanding the difference helps you spend smarter.

What Is a Probiotic?

A probiotic is a live microorganism — usually a specific strain of beneficial bacteria or yeast — that delivers a health benefit when consumed in adequate amounts. Think of probiotics as reinforcements: you're adding new troops to your gut's defensive army.

Common probiotic strains and what they do:

Lactobacillus acidophilus — supports lactose digestion and vaginal health
Lactobacillus rhamnosus — well-studied for traveller's diarrhea and immune support
Bifidobacterium longum — anti-inflammatory, supports mood
Bifidobacterium lactis — supports immunity and regularity
Saccharomyces boulardii — a beneficial yeast often used during/after antibiotics
Lactobacillus reuteri — gum, skin, and infant gut health

When to choose a probiotic

After a course of antibiotics
During or after travel (especially to new climates)
After a stomach bug or gastroenteritis
If you're noticing bloating, irregularity, or low immunity
During and after pregnancy
For ongoing digestive maintenance once your gut is in good shape

Top probiotic picks at MyVivaStore

Everyday gut health

Genuine Health Advanced Gut Health Probiotic 15 Billion, 60 caps — $44.95. Best-seller. 15 strains, shelf-stable, delayed-release capsules.

Dr Formulated Probiotics Once Daily 30 Billion, 30 caps — $43.89. One capsule a day, organic, no refrigeration needed.

High potency / after antibiotics

Genuine Health Advanced Gut Health 100 Billion CFU, 20 caps — $47.49. The reset button. Take for 1–2 weeks after antibiotics or a stomach upset.

Genestra HMF Forte 20 Billion, 50 veg caps — $44.75. Practitioner-grade, clinically studied strains.

For women

Genuine Health Women's Daily Probiotic 50 Billion, 30 caps — $41.95. Includes vaginal-health strains alongside gut strains.

Dr Formulated Women's Probiotic 50 Billion, 30 caps — $58.49. Targeted strains for hormonal and urinary tract support.

For men

Dr Formulated Men's Probiotic 50 Billion, 30 caps — $58.49. Higher potency, formulated around male gut composition.

For kids

Genuine Health Kids Probiotic, 30 chews — $26.69. Sugar-free, kid-approved chewables.

Dr Formulated Organic Kids Probiotic 5 Billion, watermelon, 30 chews — $30.09. Certified organic, gentle daily dose.

AllKidz Naturals Probiotic Gummies, 80 count — $23.69. Great-tasting gummies for picky eaters.

For mood

Dr Formulated Probiotics Mood+ 50 Billion, 60 caps — $66.49. Includes strains linked to the gut–brain axis (L. helveticus, B. longum).

What Is a Prebiotic?

A prebiotic is a type of fibre that your body can't digest, but your gut bacteria can. Prebiotics travel intact through the small intestine and arrive in the colon, where your beneficial bacteria ferment them into short-chain fatty acids (SCFAs) like butyrate — the molecule that fuels your colon cells, calms inflammation, and tightens the gut lining.

Think of prebiotics as fertilizer for the good bacteria you already have.

Common prebiotics:

Inulin (from chicory root, Jerusalem artichoke, garlic, onion) — the most-studied prebiotic
Fructooligosaccharides (FOS) — found in bananas, asparagus, leeks
Galactooligosaccharides (GOS) — found in legumes, dairy
Resistant starch — cooled rice, green bananas, oats
Partially hydrolyzed guar gum (PHGG) — gentle on IBS
Acacia fibre — slow-fermenting, low FODMAP
Slippery elm — soothing mucilage that doubles as a gut-lining repair fibre

When to choose a prebiotic

Your diet is low in fibre (most Canadians get only half the recommended 25–38 g/day)
You already eat fermented foods or take a probiotic and want to feed those bacteria
You're trying to improve regularity without a laxative
You want to lower sugar cravings (a fed microbiome demands less sugar)
You want to thicken your gut lining and reduce "leaky gut" symptoms

Top prebiotic picks at MyVivaStore

NOW Organic Inulin Powder, 227 g — $16.99. The gold standard. One scoop in water, coffee, or smoothie. Best value-per-gram on the site.

Niyama You've Gut This Prebiotic Fibre Powder, 207 g — $33.99. Multi-fibre Canadian formula — works well for sensitive stomachs.

Routine Superstar Stick, 50 g — $26.89. On-the-go single-serve sachet — great for travel or office.

Purica Fiberlicious, 250 g — $15.19. Flavoured fibre blend, family-friendly.

St Francis Herb Farm Slippery Elm, 50 ml — $17.99. For irritated or inflamed gut linings (post-illness, post-antibiotic, IBS flare).

Probiotic vs Prebiotic: The Side-by-Side Comparison

 

Should You Take Both? (Yes — and Here's Why)

If you only take a probiotic, you're sending new bacteria into a starving environment. If you only take a prebiotic, you're feeding a depleted population. Together, they create a synbiotic — the 1+1=3 of gut health.

You have two ways to do it:

Option 1 — Combo product (easiest)

NAKA Platinum Probiotic + Organic Prebiotic, Berry, 300 g — $43.19. One scoop, both jobs done. Shelf-stable, family-friendly berry flavour, great for kids and adults.

Option 2 — Stack them yourself (more flexible)

A daily probiotic capsule (your strain choice based on goals — see above)
Plus 5 g of inulin or PHGG powder in your morning coffee or evening tea

The DIY route lets you swap strains and doses as your needs change — great for people working through a specific issue.

FAQ

What is the difference between a probiotic and a prebiotic?

A probiotic is a live beneficial bacterium you consume. A prebiotic is a type of fibre that feeds the good bacteria already in your gut. Probiotics restock; prebiotics feed.

Can I take a probiotic and a prebiotic at the same time?

Yes — in fact, that's ideal. Taking them together (a "synbiotic" approach) helps the new probiotic strains survive and colonize your gut. You can take them at the same time of day or in one combination product like NAKA Platinum Probiotic + Organic Prebiotic.

Which should I take first, prebiotic or probiotic?

If you've just finished antibiotics or had a stomach bug, start with the probiotic for 2–4 weeks to repopulate, then add a prebiotic to feed the new colony. If your gut is generally healthy and you just want to support it, you can start both together.

Are prebiotics just fibre?

Prebiotics are a subset of fibre — not all fibre is prebiotic. To qualify, a fibre must (1) resist digestion in the small intestine, (2) reach the colon intact, and (3) be selectively fermented by beneficial bacteria. Inulin, FOS, GOS, and resistant starch all qualify. Wheat bran and cellulose, while healthy, are mostly bulk fibres, not prebiotics.