Probiotics vs Prebiotics: Key Differences for Gut Health
- Michaela Harron, Registered Dietitian
- Sep 4
- 3 min read
Updated: Sep 4
Medically reviewed and written by Michaela Harron, Registered Dietitian. Published September 4, 2025.
Understanding the Role of Gut Health
Your gut is more than just your digestive system. It plays an important role in digestion, nutrient absorption, immunity, and even mood. If you’ve been exploring ways to support your gut, you’ve likely heard of probiotics and prebiotics. While their names sound similar, they serve very different purposes in your digestive health. Knowing the difference can help you make smarter choices about the foods you eat and the supplements you use.
What Are Probiotics?
Probiotics are live microorganisms, often called “good bacteria,” that help keep your gut microbiome balanced.
Benefits of Probiotics
Support digestion and nutrient absorption
Strengthen your immune system
May ease symptoms of bloating and IBS
Can play a role in skin health and mood regulation
Where to Find Probiotics
Yogurt with live cultures
Kefir
Sauerkraut
Kimchi
Miso
Probiotic supplements
What Are Prebiotics?
Prebiotics are non-digestible fibres that act as fuel for the healthy bacteria in your gut. Without prebiotics, probiotics can’t thrive.
Benefits of Prebiotics
Promote the growth of beneficial gut bacteria
Improve calcium absorption
Help regulate blood sugar and appetite
Support bowel regularity
Where to Find Prebiotics
Bananas (especially when slightly green)
Garlic
Onions
Asparagus
Leeks
Whole grains such as oats and barley
Chicory root
Why Both Are Essential for Gut Health
Think of your gut as a garden. Probiotics are like the plants, while prebiotics are the fertilizer that helps them grow. Focusing on one without the other will not provide the same benefits as including both in your diet. A varied, plant-rich eating pattern with fermented foods can help build a diverse and resilient gut microbiome.
Check out our blog on the best gut health foods and explore our guide!
Prebiotics and Digestive Sensitivities
For some people, especially those living with Irritable Bowel Syndrome (IBS), prebiotics may cause discomfort such as bloating, gas, or cramps. This is because many prebiotic foods are also high in FODMAPs, a group of carbohydrates that can trigger symptoms in sensitive individuals.
What Can Help
A low-FODMAP diet (with professional guidance)
Identifying and limiting personal trigger foods
Introducing low-FODMAP prebiotic options under supervision
If prebiotics seem to worsen your symptoms, it’s important to work with a registered dietitian rather than eliminating foods on your own.
How a Dietitian Can Personalize Your Gut Health Plan
Every gut is unique. What works well for one person may not work for another. A dietitian can:
Assess your diet and digestive symptoms
Identify food intolerances and imbalances
Build a personalized eating plan
Recommend probiotic or prebiotic foods that suit your needs
Offer guidance on high-quality supplements when appropriate
Whether you’re navigating IBS, bloating, constipation, or simply want to support your long-term health, working with a registered dietitian ensures you get advice that is safe, effective, and personalized.
PS: Did you know we have a Low FODMAP focused cooking class?🌿
Living with IBS or digestive discomfort? Eating shouldn’t feel like a gamble. Our Low FODMAP Cooking Class will show you how to bring flavour back to your meals without the fear of flare-ups. Led by a dietitian, this live class includes gut-friendly recipes, live Q&A, and more!
Take the Next Step Toward a Healthier Gut
At In Good Nutrition, our team of registered dietitians is here to help you feel your best from the inside out. We offer virtual nutrition counseling designed to support your gut health, energy, and overall well-being.
Book a consultation today and discover how the right balance of probiotics and prebiotics can help you feel better every day.
FAQs About Probiotics and Prebiotics
Are probiotics or prebiotics better for gut health?
Neither is better on its own. Probiotics and prebiotics work together to support a balanced gut microbiome.
Do I need supplements, or can I get enough from food?
Many people can meet their needs through food, but in some cases, supplements may be helpful. A dietitian can guide you.
Can probiotics help with IBS?
Certain probiotic strains may reduce bloating and discomfort in people with IBS, but effectiveness can vary.
What if I can’t tolerate prebiotic foods?
Low-FODMAP prebiotic options exist and can be introduced safely under dietitian guidance.
How quickly will I notice results?
Some people notice changes in digestion within a few weeks, while for others it may take longer. Consistency is key.
