When we think about food and microbes, we tend to think in terms of an outbreak causing illness and maybe even death. Frequently, such nefarious pathogenic microbes are confused with others that produce objectionable odors, flavors or textures. Less well known, but gaining respect are the probiotics. Inspired by Molecules, Microbes and Meals I have chosen three probiotics as Microbes of the Week, which may bring back memories from my students of Food Issues and Choices (FDST2010).

This week’s post found its inspiration from my recent gastric problems. The three microbes of the week just happen to be components of Phillip’s colon health tablets, which I take twice a day to help populate my microbiome. Unfortunately, my gastroenterologist will not provide any useful guidelines as to whether I should decrease the dose down to once a day or even abandon them altogether. My dog was experiencing gastric difficulties a few months back, and she went on a regimen of probiotics sprinkled on her food once daily. Then I was told to stop dosing her as once the microbes establish themselves. Who is right, my gastroenterologist or my veterinarian? Or am I missing something?  Yoni Freedhoff states that we should be very careful messing around with our gut microflora, suggesting that we might be doing more harm than good.

Probiotics are microbes that we can ingest and are considered beneficial to gut health. Microbial cells are more plentiful in and on our bodies than human cells. The microbiome, those microbes that inhabit our gut, has been a frequent topic on this blog. We are encouraged to expose ourselves and our children to a wide range of microbial species in our food, from our pets, during birth, and even by eating dirt. Prebiotics are food substances that help feed the probiotics we add to colonize the gut. It is easy to track down information on gut health on the internet, but much of that information is contradictory and can be contaminated by advice from commercial interests.

Gut health is associated with ameliorating or preventing such conditions as autoimmune disorders, diabetes, neuronal disfunction, and obesity due to diet-driven inflammation. A diet book has been published to meet our gut-health needs, but most of what we know about the human microbiome is based on research done with animal models.  The research to date is interesting, but the science does not appear to be mature enough to provide clear, actionable guidelines. Such uncertainty does not appear to be preventing opportunists from filling the void.

My daily probiotic supplement

The microbes of the week are commonly found in probiotic supplements. In searching for credible sources on the internet I learned that Lactobacillus gasseri is anti-inflammatory, helps control Irritable Bowel Syndrome (IBS), and is effective in controlling weight. This probiotic has few side effects except for people with autoimmune conditions. Bifidobacterium bifidium is also recommended for controlling IBS, constipation, and diarrhea (both of which are symptoms of IBS), but suggests that “Older adults should avoid taking probiotics.” What? This microbe is also present in many fermented foods.

Then there is Bifidobacterium longum which appears to have similar properties to the previous organism with the same precaution for the elderly. Gaining honorable mention for the microbe-of-the-week honor is Enterococcus faecium the organism I sprinkled on my dog’s food when she had the runs after eating something she shouldn’t have on a morning walk. I have to watch her so carefully! It turns out that E. faecium is recommended to treat diarrhea, and it worked.

Conflicted is what I feel. My digestive issues were somewhat under control until about two weeks ago. I do not know whether my diet or these probiotics are letting me down. In a conversation last week, someone pointed out that I may not be feeding my probiotics with enough prebiotics. Prebiotics are food substances that allow the probiotics to prosper and colonize my gut. That may be part of the problem, but the prebiotics that I like are also high in FODMAPs, so what am I supposed to do?

My gastroenterologist is apparently only interested in treating symptoms and not at dealing with my underlying condition. My internist is good at what he does, but he is out of his area of expertise when it comes to gut health. There is no dietitian in my Health System, let alone one who specializes in digestive issues. Then again, should I even be taking probiotics at the age of 70? Where can I turn for help with my issues? If I am having this much difficulty with my understanding of microbiology, I can’t imagine what someone with less background in such matters is up against. My reason for this discussion is not to elicit sympathy, although I won’t turn any down. I am more concerned about how normal people deal with such issues. I suspect that there are many more people with such concerns than we hear or read about.

Hunting for a healthy microbiome is the topic of a recent article in Nature Outlook. The search goes way beyond digestive issues to understanding the role of the gut in the development of chronic diseases as suggested earlier in this post. Some evidence suggests that the ecosystem of the human gut is basically established by age 3, and there is very little we can do beyond that age to make major modifications. Other studies contradict that notion by indicating that guts of immigrants to the United States become “westernized” on the American diet. The price of civilization may be a trade-off of protection from infectious diseases provided by antibiotics and sanitation for a less diverse and thus less healthy microbiome. Despite my current difficulties, I will still take that trade.

The bottom line is that the more we learn about the microbiome, the more we will be able to adjust diets and treatments to improve gut health. We must proceed cautiously, however, as gut science is in its infancy, and there are many hucksters out there willing to take advantage of other people’s money, misery or unrealistic dreams. There are many more promises out there than there are concrete solutions. Let the buyer beware.

Next week: Meals—Cooking at home with industrial ingredients