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The Human Microbiome and Probiotics

Our intestines contain over 2 pounds of beneficial bacteria, about 100 trillion of these little guys, equal to the weight of the brain! These amazing bacteria live in our body all of our lives in a symbiotic relationship, playing an important role in protecting our health. They are essential to our digestion. They stimulate our immune system and help build resistance to infection. They even have the power to change which genes are active in our gut! As our understanding of our gut’s role in our overall health grows, we can also say that even our moods, appetite, food cravings, and how many calories and nutrients we extract from food are dependent on these good bacteria.

We are born with these same bacteria, inherited from our mother. Each person's population of bacteria, also known as our "microbiome" changes through our lives, reflecting the foods we eat, the illnesses we have had, the medicines we have taken. Antibiotics, poor nutrition, inflammation, stress, and other factors can kill off these helpful bacteria, tipping the balance towards more harmful bacteria that can also live in the gut. Besides digestive trouble, this can lead to all manner of body-wide inflammatory and allergic conditions developing sooner or later, including allergies, food intolerances, eczema, asthma, and autoimmune diseases. We also know that overweight, obesity, diabetes, neuro-inflammatory disorders are linked to an imbalanced microbiome.

Clearly this is important stuff! Being born by vaginal birth, having been breastfed, minimal exposure to antibiotics before the age of two, and eating a healthy diet are all important preventive measures that can set us up with a healthy microbiome for life. But, other than our diet, much of this is beyond our own control and in the past. This is where probiotics come into play. Probiotics are products that contain live microorganisms. By taking them, you replace the healthy types of bacteria in your gut, returning to a more healthy balance. Prebiotics are also products you can find; they provide the food that our healthy bacteria eat and thus support their growth and activity. They are usually carbohydrates that are not digested by humans, and can be found naturally in these foods: honey, onions, whole grains, asparagus, rye, bananas, maple sugar, and oats. A diet rich in a variety of healthy fruits and vegetables reasonably would supply a good amount of these prebiotics. "Synbiotics" are products that mix probiotics and prebiotics.

Research has proven probiotics to be useful in many ways, not just protecting from antibiotics. They can decrease the length of symptoms in a diarrheal illness. They can diminish the development and severity of food allergies, eczema, and other allergy symptoms. There is also evidence that probiotics can benefit people with Irritable Bowel Syndrome (IBS), Crohn's Disease, Ulcerative Colitis, liver disease, infants with colic, and even the common cold!

There are many different probiotics on the market. In general, the product with the most variety of species listed will be the best. Bifidus-type may be the most useful with constipation and other gastrointestinal disorders. Saccharomyces has been studied most in relation to diarrheal illness. Avoid Enterococcus species, as this can cause infections. If possible, choose probiotics that are refrigerated, as this helps the bacteria survive longer. Probiotics come in doses of orders to the millions and billions (in CFU's, or colony forming units), usually dosed higher for more severe symptoms. Children are often given doses in the 1x10^8 range, and there are many products tailored to these pediatric doses. As probiotic capsules can be pricey, a thrifty alternative is to take ¼ teaspoon Red Star yeast, rich in Saccharomyces, twice a day in a glass of warm water or in food.

Various sources recommend taking probiotics daily anywhere from 2 weeks to 2 months to fully replace the bowel's healthy bacteria after a course of antibiotics. For other conditions, people often need daily doses for longer time periods. If taking antibiotics at the same time as probiotics, it is best to take them at least 2 hours apart from each other. Start the probiotic as soon as possible and continue it until at least a few days after the antibiotics are done.

For most people probiotics are extremely safe. There are few side effects, but occasionally people feel more gassy when first starting probiotics or prebiotics. If you have a weakened immune system, speak with your health care provider first, as there are a few reports of the bacteria entering the bloodstream.

You may be wondering about probiotics in foods. Humans have consumed fermented foods for as long as civilization, both as a way to preserve food and to improve health. Sauerkraut, yogurt, tempeh, miso, kefir, kimchi, and kombucha are all examples. Whatever the food, be sure it says "live cultures" on the packaging. Consuming these foods regularly is certainly a way to get probiotics in through your food and boost your digestive health, but it is difficult to gauge the dose you are getting each time. For the adventurous, and for those who perhaps recall their parents or grandparents doing this, you might even think about making your own sauerkraut-- it's incredibly easy! Canned sauerkraut has been processed at high heats and there are no live bacteria; a home batch, instead, provides a multitude of helpful bacteria. There is currently a nationwide “foodie” fermentation trend; no reason not to jump on the bandwagon and experiment, too!

If you have more questions, feel free to visit your provider at Tecumseh Family Health to discuss further.

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