Common Sense Health

Probiotics:  What Are They and What Do They Do?

By: Maureen McDonnell


There’s quite a buzz these days about probiotics and for good reason. These ”friendly” bacteria that live in our gut do amazing things for our health. In our intestinal tract, we house trillions of bacteria… some good, some not so good. As long as these organisms live in harmony… meaning the good ones keep the bad ones in check, we have balance and a healthy gut. ­­­ However, when that delicate balance is disturbed (referred to as dysbiosis) as a result of taking oral antibiotics, from stress, consuming excess sugar, and eating processed or pesticide-laden food, our gut health, and therefore our overall health suffers.



What do probiotics do?

It is estimated that probiotics have over 30 positive actions in the body including: crowding out bad organisms such as yeast and bad bacteria, supporting immune function (since 80% of the immune system is headquartered in the gut), assisting in the absorption of nutrients and the elimination of toxins (including heavy metals), protecting against food poisoning, synthesizing B vitamins, regulating bowel movements and limiting bacteria that produce cancer-causing nitrates. Also, since 90% of the mood- stabilizing neurotransmitter Serotonin is manufactured in the gut, they are also involved in our mood and sleep patterns. You can find over 200 published studies highlighting the benefits of probiotics at



How do we initially get probiotics in our GI system?

When a baby passes through the birth canal, it is exposed to mom’s bacteria at which time it begins to lay down colonies of its own good bacteria in the intestinal tract. This in turn sets the stage for a healthy immune system. Recent studies (1) confirmed that babies born via C section (32% of all births) have higher incidences of allergies, eczema and asthma… all conditions of a dysregulated immune system. Regardless of the method of delivery, all children who consume breast milk will receive an inoculation of probiotics. It is estimated that colostrum has 40% probiotic content.



Sources of probiotics:

Although I still consider a high quality capsule of probiotics to be a wonderful option, it turns out there are many food sources that provide very high levels of these friendly organisms. Most people immediately think of yogurt as a source. However, when tested, commercially prepared yogurt and Kefir often contain very few living organisms. Luckily, Donna Gates, author of Body Ecology, and others have simple recipes for making homemade yogurt and cultured vegetables as well as other items that can help repopulate our gut with good flora. Recipes and videos for making some of these foods can be found at: Additionally, most local health food stores carry organic and often locally made yogurt, kefir, Miso, Kimchi, natto, Tempeh and Kombucha all of which are great sources of good friendly bacteria.


Here’s what to look for if purchasing probiotics in a capsule form. Make sure it is a high potency formula with at least 25 billion CFUs (colony forming units). A good brand usually contains multiple species (not just one, such as Acidophilus). A wonderful brand I recommend is by ProThera. You can find it at and it contains all of these and more: Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus saivarius, Lactobacillus casei, Planarum bifidobacterium, Bifidobacterium breve and much more.


Usually, the best formulas require refrigeration to keep the organisms alive.



When to take Probiotic Capsules?

During the 30 plus years I’ve been taking and recommending to my clients that they take probiotics (especially if they are on antibiotics), I’ve witnessed many “experts” debate about the best time of the day to ingest them. Should they be taken at the end of a meal since the PH of the stomach is somewhat lower and less likely to kill off the good bacteria? Another argument for this option is that most bacteria (good and bad) that normally enter our system do so with food. Or, should they be taken first thing in the morning on an empty stomach with a big glass of water as Dr. Mercola recommends? Currently, I am going with the empty stomach first thing in the morning option. I’m not sure I’m 100% correct or if anyone has solved this riddle with complete certainty, but what I do know beyond a shadow of a doubt is that it is not recommended to take probiotics at the same time as an antibiotic or the antibiotic will destroy all the good friendly organisms.


Prebiotics? Prebiotics mostly come from carbohydrate fibers called oligosacchariedes and they are non-digestible. Basically they serve as food for the friendly bacteria as they help them grow and flourish. Sources include root vegetables, such as chicory root and wild yams and garlic, plus kale and bananas. Fructooligosaccarides can also be taken as a supplement but you have to be careful… too much too quickly and you’ll develop gas. Studies in adults have shown prebiotics can help increase calcium and magnesium and in infants they’ve shown they can positively affect immune function. Due to this synergistic effect, some probiotic formulas now contain prebiotics.


Because of their wide range of positive effects on symptoms such as GI disturbances, depression and immune disorders (to name only a few), many experts in the bowel ecology field such as Dr. Valery and Dr. Smirnov feel probiotics should be considered a priority supplement for those seeking optimal health. The following prediction, found on seems noteworthy: “probiotics will be the antibiotics of the 21st century. This is because their effective medical implementation will revolutionize our perspectives on disease in the way antibiotics did before.”




Kalliomaki, M., & Isolauri, E. (2003). Role of intestinal flora in the development of allergy. Curr Opin Allergy Clin Immunol, 3(1), 15-20.


Bager, P., Wohlfahrt, J., & Westergaard, T. (2008). Caesarean delivery and risk of atopy and allergic disease: meta-analyses. Clin Exp Allergy, 38(4), 634-642


Grölund, M.-M. L., Olli-Pekka; Eerola, Erkki; Kero, Pentti. (1999). Fecal Microflora in Healthy Infants Born by Different Methods of Delivery: Permanent Changes in Intestinal Flora After Cesarean Delivery. Journal of Pediatric Gastroenterology & Nutrition, 28(1), 19-25.




Maureen McDonnell has been a registered nurse for 35 years (in the fields of childbirth education, labor and delivery, clinical nutrition, and pediatrics.) She is the former national coordinator of the Defeat Autism Now Conferences, and the co-founder of Saving Our Kids, Healing Our Planet. Maureen lectures widely on the role the environment and nutrition play in children’s health. She is the health editor of WNC Woman Magazine and owner of Nutritionist’s Choice Inc. Presently, Maureen serves as the Medical Coordinator for the Imus Ranch for Kids with Cancer. She and her husband have five grandkids and feel blessed to be living in the beautiful mountains of North Carolina.




Maureen McDonnell, RN
Written by Maureen McDonnell, RN