What are prebiotics? And what’s the difference between prebiotics and probiotics and fiber? In this article and episode of TGIF, I talk about prebiotic definition, prebiotic foods, and prebiotic health benefits. If you’re thinking of using prebiotics to fix your gut health problem, consider a comprehensive and customized gut healing program. Click to schedule a phone consultation call.
Prebiotics are non-digestible fibers that act as fertilizers for the good bacteria in your gut. For a food to be considered a prebiotic, it must:
- Resist the acidity of the stomach (not get destroyed by the acidity), resist digestion, and not get absorbed in the upper gut (small intestine)
- Get fermented by bacteria in the colon (or large intestine)
- Stimulate the growth and the activity of healthy and beneficial bacteria in the intestine
Our bodies can’t make prebiotics—we must obtain them from plant fibers. They help improvethe ratio of good-to-bad bacteria, preventing or treat dysbiosis. As a result, they help with overall health and wellbeing including improved gut health, digestion, immune, as well as reducing inflammation, stress, anxiety, and depression.
Learn how to identify the REAL causes of your gut problems.
Prebiotics vs. Probiotics
What’s the difference between prebiotics and probiotics?
Prebiotics are plant fibers that help nourish and feed the bacteria in your gut. They promote the growth of healthy bacteria.
Probiotics are the actual live bacteria that you obtain from fermented foods (like sauerkraut) or probiotics supplements.
Prebiotics are the food for probiotics. With an ample amount of prebiotics in your diet, the healthier the live bacteria in your gut will be and the healthier your gut and whole body will be.
Prebiotics vs. Fiber
What’s the difference between prebiotics and fiber? Is fiber and prebiotics the same thing?
No. They’re not the same.
Prebiotics are a type of fiber. All prebiotics are fiber, but not all fibers are prebiotics. There are many types of fiber. The classical types are insoluble fiber—they don’t dissolve in water and don’t get fermented by gut bacteria and microbes—and soluble fiber—they dissolve in water and get fermented by gut bacteria. Prebiotics are a type of soluble fiber. Most plant foods contain both types of fiber in different proportions.
If you want to get the health benefits of prebiotics, you must focus on eating prebiotic-rich foods, not just high-fiber foods.
Watch Episode 11 of Thank Gut It’s Fixed Show on Prebiotics!
The two main types of prebiotics are inulin and oligofructose (sometimes also called fructo-oligosaccharide or FOS). Inulin and oligofructose are found in many vegetables and fruits, and you’re probably eating them without realizing.
Cooking causes losses in the amount of prebiotic in the food. Whenever possible, consume these foods raw. If you must cook them, saute quickly or steam with a little bit of water without overcooking to preserve as much prebiotic fibers as possible.
Learn how to identify the REAL causes of your gut problems.
These are the foods highest in prebiotics and suggestions for including them:
- Acacia gum (or gum Arabic): mostly found in fiber supplements or in fiber-fortified foods. You may add it to smoothies.
- Onions, garlic, shallot, leek: these vegetables are great for adding flavor and aroma to your meals! Saute onion and garlic with almost any meal. Make leek soup. Add to omelets. Eating them raw will provide your body with the most amount of prebiotic. However, these foods can cause bloating and stomach pain. Read below in the caution section.
- Apple skin: that’s why I don’t recommend peeking apples! Buy organic apples as they tend to be one of the highest pesticide-containing fruit.
- Under-ripe banana: just eat! A serving of fruit is half a banana or buy small ones as bananas are concentrated in sugar.
- Asparagus (raw is better): my favorite cooking method is roasting in the oven. Place asparagus stems on a baking sheet. Drizzle some olive oil, salt, and pepper. Cook in the oven at 350 for 15-20 minutes. I like them to stay crunchy and not too mushy.
- Dandelion greens: toss in a salad. They may have a bitter taste raw. To cook, saute some garlic and onion (more prebiotics) in olive oil on medium heat, add dandelion greens and cook for few minutes. Squeeze fresh lemon to counter the bitterness. You can also add them to smoothies.
- Jerusalem artichokes (sunchokes): Cook them like you would cook potatoes. Try roasting in the oven.
- Chicory root (tea and powder): brew chicory root tea. It’s a great alternative to coffee.
- Jicama: the taste is close to an apple but a bit bitter. peel and cut into sticks like carrots or thin slices like cucumber. Use to dip hummus or guacamole. The kitchn has a good article on using jicama.
Prebiotics Health Benefits
Before going into the health benefits of prebiotics, you might wonder how or why prebiotics work:
- Prebiotics improve the ratio of good-to-bad bacteria.
Prebiotics improve the numbers of bifidobacteria and lactobacilli (healthy) compared to Enterobacteria and clostridia strains (pathogenic) in the gut. Less Bifidobacteria and less bacterial diversity is associated with higher inflammation and irritable bowel syndrome (IBS).
- Prebiotics increase the acidy of the colon (reduces pH).
Increased acidity helps prevent the growth of pathogens. It also reduces the production of toxic compounds like ammonia, amines, and phenolic compounds in gut.
- Prebiotics produce short chain fatty acids (SCFA)
The 3 main SCFAs are butyrate, acetate, and propionate. SCFA nourish the cells of the intestine, with butyrate being the preferred energy source of the cells that line the colon. It’s needed for making new healthy cells and improving their structure. Propionate lowers the production of cholesterol in the liver, and is potentially one of the reasons why eating fiber lowers cholesterol. SCFA also improve the function of immune cells and improve and the absorption of calcium and magnesium.
Because of these benefits, prebiotics have been shown to:
- Reduce gut inflammation
- Improve gut barrier function (reduce leaky gut)
- Improve immune system and ability to fight bad bacteria
- Reduce symptoms of IBS, including diarrhea, bloating, stomach pain, and constipation
- Reduce antibiotic-associated diarrhea
- Reduce symptoms of IBD (Crohn’s disease and colitis)
- Improve digestion of lactose
- Increase the bioavailability and absorption of calcium and magnesium, minerals necessary for bone health and preventing osteoporosis
- Increase the absorption of iron
Improve mental health, such as reduction in anxiety, depression, and stress, and improvement in mood
Warning: Prebiotics Side Effects
While there are many advantages to eating prebiotic foods, they may cause undesirable side effects like bloating, cramping, and stomach pain for some people. If you have an existing imbalance in your gut flora, or if you have bacterial overgrowth in the small intestine (SIBO), the addition of prebiotic foods can worsen your symptoms. If this is your case, I highly recommend that you seek customized gut healing nutrition program (you can read about my program here and schedule a complimentary discovery session here).
To be on the safe side, start introducing prebiotic foods slowly, especially if they are not foods you eat on regular basis. Start with cooking onion, garlic, leek, etc. Start with a small amount of jicama and Jerusalem artichokes. If you can tolerate this amount without side effects, you can try a larger amount or raw more confidently.
- Slavin. Fiber and Prebiotics: Mechanisms and Health Benefits. Nutrients. 2013, 5, 1417-1435.
- Justin L Carlson, Jennifer M Erickson, Beate B Lloyd, Joanne L Slavin; Health Effects and Sources of Prebiotic Dietary Fiber. Current Developments in Nutrition. 2018: 2, 3.
- Jung TH, Jeon WM, Han KS. In Vitro Effects of Dietary Inulin on Human Fecal Microbiota and Butyrate Production. J Microbiol Biotechnol. 2015 Sep;25(9):1555-8.
- Cummings JH, Macfarlane GT. Gastrointestinal effects of prebiotics. British Journal of Nutrition. 2002, 87, Suppl. 2, S145–S151.