Pre-Biotics and Pro-Biotics

By Parul Kharod

In 1683, scientist Antony Van Leeuwenhoek was the first to discover that millions of tiny bacteria and viruses live in our bodies. It took about 300 years since this first observation for us to really understand the importance of these creatures that live inside us. In 2012 the National Institutes of Health completed the first phase of the Human Microbiome Project, a multimillion-dollar effort to catalogue and understand these microbes.

We have 100 trillion or so microbes that live in various nooks and crannies of the human body. The largest colonies are in our gut. These beneficial bacteria within the body have an enormous influence on our metabolism, our hormones, and our genetic makeup.

These microbes help us get the nutrients from our food, help balance our mood, sharpen our focus, and help build our immune system. The quantity and variety of these microbes is the secret to a long and healthy life. When these microbes thrive, our metabolism is at its best. When our microbiome is out of balance, we can get all sorts of disorders such as weight gain, leaky gut, frequent sickness, and more serious chronic diseases due to increased inflammation in the body. How our body responds to various medications, drugs, painkillers, allergens and antibiotics and other stressors all depends on our microbiome.

The Human Microbiome Project and The American Gut Project are two large projects that have studied the bacteria living in our gut. Just as we have neurons in our brain, we also have neurons in our gut – including neurons that produce neurotransmitters like serotonin. In fact, the greatest concentration of serotonin is found in our intestines, not the brain. A majority of our immune system is also in our gut.

There is a lot of research being done on how the gut environment affects our overall health. Results point towards a direct connection between gut health and a range of issues such as obesity, depression and anxiety, chronic inflammation, cancer, diabetes, and obvious GI issues such as IBS.

Poor diet and long-term chronic use of antibiotics and antacids is said to be detrimental to the quality and quantity of gut bacteria causing long-term consequences.


The Gut Microbiota, also known as the “Intestinal Microflora" or “Gastrointestinal flora" is a thriving colony hosting about 300 –1,000 species of bacteria. Since these bacteria support good health and are vital to a good life, they are known as probiotics. The word 'probiotic' is Greek, meaning Pro (for) + biotic (bios) (life) = For Life.

Probiotic Foods

Probiotics are live beneficial bacteria that can be added in food or supplement form to improve microbial communities in our gut. These active cultures help improve or populate the quantity and variety of bacteria in our gut. Here is a list of foods that have live cultures:

• Fermented dairy foods such as yogurt, kefir and aged cheeses
• Kimchi and Sauerkraut
• Miso and Tempeh
• Kombucha
• Kaanji
• Fermented batter products such as Idli, Dosa, Dhokla
• Homemade pickles (in limited amounts)


In order for the probiotic bacteria to survive in the gut, they need to be fed. We have to constantly feed the good bacteria. The most important nutrient that these microbes need is fiber! Research shows that when you don't eat good fiber-rich foods to feed these bacteria, they start eating away the mucus lining of your intestines. This is what causes leaky gut and increases inflammation and triggers autoimmune disorders.

Prebiotic Foods

To get enough natural fiber:

Eat a variety of whole fruits and vegetables. Avoid juicing which throws away the pulp thus losing all the fiber.

Eat a variety of whole grains. Eat intact whole grains and avoid processed foods made from flour (atta or maida).

Eat a variety of legumes, pulses, peas, beans, and lentils. Sprout beans to make them digestible and increase other nutrients.

Beware of products like yogurt, ice-cream, chocolate, enhanced waters, or energy bars that have added isolated fibers.

Reduce the amount of packaged and processed foods you eat

Why your overall diet matters and taking a fiber pill is not the solution?

There are many products on the market with added fibers. Research shows that isolated fibers and fiber supplements may help relieve constipation but they do not help with other benefits such as lowering blood sugar and cholesterol or to feed the healthy gut bacteria. So, eating foods naturally rich in fiber is very important for health.

It's not just a myth or an old wives' tale – we are what we eat. Our microbiome is made up of how we choose to fuel our gut. Microbiologists have known for some time that different diets create different gut flora. Ayurveda claimed thousands of years ago that our health is tied to our digestion.

If you want to feed the pathogens (bad bacteria), eat and drink foods that are processed, filled with sugar, chemicals, flour, unhealthy fats/oil, GMO's, etc. You will quickly make these pathogens happy and help them populate. If you want to feed your good gut flora, all you need to do is simply feed it with real foods that are naturally high in fiber!


Parul Kharod, MS, RD, LDN is a registered dietitian and licensed nutritionist and works as a Clinical Dietitian with Outpatient Nutrition Services at WakeMed Hospital in Cary and Raleigh. She can be reached at