Prebiotics vs. Probiotics: What’s the Difference?

Although their names are similar and they are both important for digestion and overall health, prebiotics and probiotics play different roles in the body. Here is a full breakdown of prebiotics vs. probiotics; what they are, their health benefits, and where to find them.

What’s the difference between prebiotics and probiotics?

Prebiotics are a group of nutrients that help to stimulate the growth or activity of beneficial gut bacteria in the body, while probiotics are bacteria found in the gastrointestinal system that have a positive effect on health ^{(1, 2)}.

Prebiotics are a special form of indigestible plant fiber in fiber-rich carbohydrate foods such as vegetables, fruits, and whole grains. Prebiotic fiber passes through the digestive system untouched until it reaches the colon, where it is used as a source of food to encourage the growth of the friendly bacteria in our gut, also known as probiotics.

Probiotics are tiny microorganisms, including live bacteria and yeast, that live in the gut and are beneficial for health. The different strains of probiotic bacteria support the diverse population of healthy microbes in the gut. Probiotics occur naturally in fermented foods such as yogurt, sauerkraut, and miso, and can also be found in supplement form.

Together, prebiotics and probiotics build and maintain a healthy colony of bacteria in our gut, which supports our overall health.

	Prebiotics	Probiotics
Definition	Form of indigestible plant fiber in fiber-rich carbohydrate foods that feed good bacteria and promote gut health.	Tiny microorganisms, including live bacteria and yeast, that live in our gut and are beneficial for overall health.
Benefits	– Produce short-chain fatty acids (SCFAs) – Improve mineral absorption – Promote satiety – Out-compete pathogens – Feed good bacteria	– Improve digestive health – Boost overall immunity – Reduce inflammation – Boost mood and cognitive function – Reduce stress and anxiety
Sources	Vegetables, Fruits, Legumes, Grains, Roots	Yogurt, Kefir, Tempeh, Natto, Fermented Vegetables, Some Cheeses

Benefits of Prebiotics and Probiotics

Trillions of bacteria and microorganisms live in our gut and are collectively referred to as the gut flora or gut microbiota and play vital functions in the body and influence our overall health. The consumption of prebiotics and probiotics plays an integral role in supporting a healthy gut microbiota, which has been shown to ^{(3, 4, 5, 6)}:

• Improve digestive health
• Improve mineral absorption
• Restore stomach acid
• Modulate the immune system
• Improve satiety, thereby supporting weight loss
• Reduce the risk of irritable bowel syndrome (IBS)
• Promote metabolic health, including insulin resistance, healthy blood lipids
• Reduce the risk of allergy
• Improve mood and cognitive function
• Lower overall inflammation

Which foods are prebiotic?

The most common forms of prebiotics include fructooligosaccharides and galactooligosaccharides, which are found in certain high-fiber foods, and inulin is the most common fructooligosaccharide and is found in a wide variety of plant foods. The most prebiotics-rich foods include:

• Apples
• Asparagus
• Bananas
• Barley
• Chicory root
• Dandelion root
• Garlic
• Jerusalem artichoke
• Leeks
• Legumes
• Mushrooms
• Oats
• Onions
• Rye
• Wheat

Which foods are probiotic?

Probiotic foods are made via fermentation; a natural method of food preservation that was used by various cultures for centuries. The process of fermentation allows bacteria, yeast, or fungi to convert the natural sugars found in foods (glucose, fructose, and sucrose) into lactic acid, which creates beneficial bacteria, and probiotics, in the process. The most probiotic-rich foods include:

• Yogurt
• Kefir
• Sauerkraut
• Tempeh
• Kimchi
• Buttermilk
• Miso
• Kombucha
• Natto
• Fermented vegetables
• Some cheeses

Is it better to take prebiotics or probiotics?

Both prebiotic and probiotic foods should be consumed as part of a healthy diet. By prioritizing whole foods and creating well-balanced meals with fruits, vegetables, whole grains, beans, and lentils, you can help to ensure you are consuming adequate prebiotic-rich foods, and by including fermented foods regularly in your meals, you can help to ensure you are consuming adequate probiotic-rich foods.

In addition to food, both prebiotics and probiotics can be found in supplement form. Probiotics supplements can be found in pill or powder form at major grocery stores, health food stores, and pharmacies. Prebiotics can also be found in supplement form; however, prebiotic fiber is much more readily available in food than probiotic bacteria through a conventional diet.

Who should take prebiotic or probiotic supplements?

Every human gut microbiota is a unique fingerprint and collection of bacteria. Although prebiotic and probiotic supplements have been shown to have many health benefits, they are not for everyone.

While there is evidence to support the use of probiotic supplements for a variety of indications beyond gut health, the applications and results are strain-specific. Should you choose to take a probiotic supplement, it’s vital that you do your research or speak to a health professional to determine what type of bacteria will work best for you ⁽⁷⁾.