The gastrointestinal tract is the barrier between the outside world and the inside of our bodies.  Pretty much anything that we put into our mouth either gets digested and absorbed to be utilized or stored by our body, or gets excreted as either solid or liquid waste.

Research has shown that our GI (gastrointestinal tracts) contain between 2-6 pounds of gut flora (bacteria, viruses, fungi, parasites, etc).  These microbes (also called flora, or living organisms) can be helpful, harmful or neutral.  Due to necessary and sometimes unnecessary use of antibiotics to treat illness, environmental chemical exposures, and use of antibiotics in our food sources, the population of flora in our GI tract can be greatly altered.

If the balance between the good and bad flora shifts, this can lead to significant issues; such as improper digestion of foods, malabsorption of nutrients, overabsorption of nutrients leading to weight gain, and possibly a breakdown in the gut barrier.    This breakdown in the gut barrier theoretically can enable toxic substances and possibly microbes to enter into the bloodstream.   Our bodies have multiple ways to defend against bacteria and toxins transiently entering our body and bloodstream.   However sometimes these defense mechanisms may not work properly and illness can ensue.

The process of fermenting foods increases the beneficial bacteria count in the foods, and makes nutrients more bioavailable or easier for the body to absorb.    Eating fermented foods, seems to help better regulate the immune system.   Fermented foods can contain a wide variety of beneficial bacteria and the levels found in these foods far exceeds the level of beneficial bacteria found in over-the-counter supplements.  Consuming probiotic supplements alone though, hasn’t really been shown to increase the levels of beneficial bacteria in the gut.   Adding  prebiotics found in fermentable fibers (chicory root, Jerusalem artichoke, yams, dandelion greens, leeks, onion, garlic and banana) have been shown to stimulate the grown of beneficial bacteria in the gut.  Therefore it is recommended to consume both prebiotics and probiotics.

It is crucial to introduce fermented foods, such as sauerkraut, kimchi and kombuchi very slowly into the diet.  This is because fermented foods can have high levels of histamine and aldehydes.  Histamine is substance that causes a local immune response such as hives, rashes, nausea etc.   Some people have decreased ability to break down histamine or aldehyde quickly and therefore can be intolerant to higher levels of these substances.  If you notice that when you eat fermented foods, you develop headaches, abdominal pain and bloating, hives, rashes or nausea it may be due to the high histamine or aldehyde load.    In this case, one would require an individualized assessment to determine the safety of consuming such foods.

Raw fermented foods are becoming more readily available for purchase.  In addition, there are more kits available to ferment foods at home.  It is important to realize that when commercially purchased, fermented foods are often pasteurized or preserved for safety.  This kills the beneficial bacteria.  In addition, commercially available foods often contain high amounts of refined sugar and processed dairy.     Therefore, the benefit of foods such as kefir and yogurt, that have a high concentration of probiotics, is offset by the amount of sugar and processed dairy.   As was discussed last week, pasteurized dairy can have many unwanted side effects.

If possible it is best to select foods such as sauerkraut, kombuchi and kimchi rather then milk based products such as yogurt and kefir.  When eating yogurt and kefir it is recommended that you select full fat products without any additional sweeteners or sugars added.

Currently, there is a fair amount of debate in the literature regarding prebiotics, probiotics and fermented foods.  Just remember no one specific food or supplement is best for everyone.   We all have different genetic make ups and environmental factors that influence our responses to food and supplements.

Hope this helps to bring some light onto the subject of probiotics and fermented foods!