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Prebiotics: What Are They and Why Do You Need Them for Optimal Health

By May 21, 2018June 6th, 2020No Comments

Not all bacteria is created equal!

Probiotics are the healthful bacteria that you may frequently read about; probiotics are touted as being key for overall health, blood sugar control, weight management, and potentially more. Probiotics aren’t totally new in the news, but PREBIOTICS are newer on the scene (not actually but in terms of our awareness of them) and they’re perhaps even more important than the probiotics themselves.

Why is it that prebiotics may be even more important than probiotics? This is because they’re the food to keep the healthy bacteria alive and well.

What are they exactly? Prebiotics are the important non-digestible fibers that help promote the good bacteria in our gut and are found in various fruits, vegetables and whole grains such as bananas, onions, garlic, leeks, asparagus, artichokes, and soybeans. Think of prebiotics as the good bacteria promoters, and probiotics as the good bacteria. Probiotics are crucial to help the probiotics aid our gut health and gain more good bacteria!

Prebiotics and Mental Health

As for mental health, where do prebiotics come into play? There is a lot of new research being done on the gut-brain connection, and it is becoming more clear that mood-related disorders and hormonal imbalances are highly tied to our gut health.

An Oxford study tested two probiotics B-GOS (Bimuno-galactooligosaccharide) and FOS (fructooligosaccharide), on healthy adult volunteers to assess their impact on the volunteers’ mood. Volunteers who took the B-GOS prebiotic vs the placebo had lower levels of cortisol after the three week study and responded better to an emotional test that assessed attention to negative vs positive words.

While these findings are preliminary and more extensive research will need to be done, this could be an indicator that prebiotics may have a positive connection in regards to stress-related disorders such as anxiety and depression.

Think about how you feel when you don’t eat enough throughout the day. You may feel a little dizzy, lightheaded, feel irritated or sad, have trouble focusing. Vice versa, think about what can happen to your digestive system when you are stressed or anxious. You may develop stomach pain or indigestion.

Research is finding a strong connection between your gut and brain and how important nutrition is for us to keep our minds healthy! At a deeper level, our gut metabolizes nutrients from the food we eat to support neurotransmitter functions that control our mood and help us fight stress (check Isabel’s recent post about cortisol and foods to combat fight stress!).

Animal studies have shown that bacteria that is present early on in life affect the development of the stress system and how the animal responds to stress in adulthood.

Prebiotics and Your Body

So, now we know how probiotics help our minds, what about the rest of our body? Since the health of our gut is closely tied to many other bodily functions, prebiotics (along with probiotics) are important optimal health and over-all wellness.

Better Gut Health and Digestion

Prebiotic foods may help to increase the good bacteria,  including Lactobacillus rhamnosus GG, L. reuteri, bifidobacteria, and certain strains of L. casei or the L. acidophilus-group.

This healthy bacteria is able to use the fiber from the foods that we eat (usually non-digestible) as a source of their own nutrition. When  our gut bacteria metabolizes this food, create a biproduct of short-chain fatty acids that are really really good for us.

Short-chain fatty acids also help regulate electrolyte levels in the body, which is crucial for proper digestion, and also help promote healthy intestinal lining.

Research has demonstrated that gut microflora number and environment contributes to inflammatory bowel disease, ulcerative colitis, and Chron’s disease.

Improved Immune System

Studies have suggested that prebiotic’s ability to promote healthy gut bacteria, specifically the microflora that helps boost immunity. Prebiotics and probiotics help the immunes system also because they allow us to better absorb important nutrients and trace minerals from the foods we eat.

Prebiotics also help regulate our gut pH, which is so important to preventing the  growth of potential pathogens or damaging bacteria.

Lower Inflammation

Inflammation is a root cause to many disease including heart disease, neurological disease, autoimmune disease, and more. Imbalance of our microbiome bacteria in our gut has a been demonstrated in research to influence low-level inflammation, further perpetuating inflammatory diseases like dementia, diabetes, cancer, and the number one cause of death in the US heart disease. Prebiotics can help to promote a healthy gut environments, and help to decrease this inflammation found throughout the body.

Promote Healthy Weight

With more processed foods in our diets, we aren’t getting as many prebiotic rich foods in our daily nutrition. We have seen obesity rates dramatically increase, leading scientists find the relationship between those two things.

What they found is that prebiotics improve the body’s feelings of satiety and improve insulin sensitivity,  suggesting that having an probiotic friendly environment in our gut helps to make us feel more fuller longer. While scientist are still trying to pinpoint this exact connection, there is definitely a correlation between adding prebiotic rich foods, and helping maintain a healthy weight.

Prebiotic Foods

Now you’re probably wondering how do you get more prebiotic foods in your diet. Don’t worry, we’ve got you covered! Here’s a list of 8 prebiotic foods you can begin incorporating into your diet!

  1. Bananas

  2. Dandelion Greens

  3. Garlic

  4. Onions

  5. Leeks

  6. Chicory

  7. Jicama

  8. Artichoke

Also, check out these prebiotic rich recipes here:

Strawberry Cocoa Smoothie

Kale and Avocado Salad with Pomegranate and Avocado

Garlicky Bok Choy 

To sum it up: prebiotics promote probiotics, which promote a healthy gut, which promote a healthy brain and good moods! Eating healthy, whole foods are essential for optimal brain functioning, immune function, and overall health.


We’re so excited to have Kathleen interning for us here at ISN! Kathleen graduated from UMass Amherst in May with her BS in Nutrition and Dietetics. She is starting her Dietetic Internship in NYC March 2018! Growing up she knew she wanted to work in a field that allowed her to help others, and as she got older she became more drawn to the health and wellness world. Kathleen knew she found her calling from her very first nutrition class at UMass and knew she wanted to be a RD. She is passionate about leading an active, healthy lifestyle, intuitive eating, and recently acquired her 200 hour yoga teacher certification. Kathleen is so excited to share her passion with all of you!