By Kirsten West ND, LAc

A fascinating article was printed in the New York Times only a few days ago[i]. The article dives into looking at our health from inside out, which is what we always do at Optimal Terrain.

Many of you have listened to me speak about the importance of gastrointestinal health and, with this, ask about your stools, their consistency, and related GI symptoms. (Yes, flatulence included.) There is a good reason I do this. By asking these questions I get a peek into your microbiome and ultimately, a peek into your health.

Believe it or not, if the cells in the human body were to be analyzed and counted, we are made up of more bacteria than human body cells. (It makes me wonder: who’s really running the show here?) Everyone’s skin swarms with an invisible smorgasbord of bacteria, and the mouth is a microbial wonderland. Various viruses, bacteria, fungi and protozoa in our bodies — called the microbiome — supply us with critical vitamins, help fight dangerous pathogens, keep the immune system in balance, and modulate weight and metabolism by extracting energy and calories from the food we eat.

The identity and abundance of species that compose the human microbiome — which is found throughout the body, including on the skin and in the nose, mouth, tonsils, lungs, guts and genital tracts — vary from person to person, depending on factors like whether we were breast fed or formula fed, the nature of our births- i.e., vaginal birth vs. c-section, by our diets, geographic location, environmental exposures and medical history (previous infections, medication use, etc.).

Notably, it’s the 500 or so species of bacteria residing in our gastrointestinal (GI) tracts that really make us tick.

Our microbiome helps to inform and structure our immune function, mood, hormonal balance and metabolism (among others.) New studies are coming out daily and so far, it has been discovered that obese individuals tend to have similar gut bacteria. A 2006 study at Washington University in St. Louis’s School of Medicine found big differences between the collections of gut bacteria in heavy people and their slender peers.[ii] The roles of heredity, diet and exercise notwithstanding, researchers suspect some people’s bacteria are simply better at helping them stash away calories.[iii]

In addition, a greater level of happiness and less anxiety have been related to specific microbiome compositions[iv], those with a microbiome of greater diversity tend to be healthier[v], with less risk for cancer[vi], and caloric restriction, with a greater intake of vegetables, equals greater immune resilience[vii]. We also share our microbiome, as married couples tend to have a similar GI bacterial make-up[viii]. The old adage, “you are the company you keep”- may have more meaning then we thought.

It has also been found, that our microbiomes helps to produce and balance our neurotransmitters[ix]. In fact, we have more serotonin in our guts than our brains. That “gut feeling” is real.

So the biggest question we must ask ourselves is this: How do we create and keep a healthy microbiome? Just as the New Year prompts lifestyle make-overs, can we do this with our gut as well?

The answer is yes. However, it is not as easy as a probiotic or buying stock in yogurt companies.

A new study published in Cell Host and Microbe[x] outlines a research which helps us to understand how we may be able to influence and change our own population of gut bacteria. This study was performed by transplanting varied human gut microbiomes into mice. Two primary microbiota were used: (1) microbiomes from people eating the SAD (Standard American Diet); a dietary intake of upwards of 3,000cal/day, and largely made up of animal proteins and very low in fruits and vegetables, and (2) the microbiomes from people who ate less than 1800 calories a day, consumed far less animal protein, less carbohydrates, and with high vegetable and some fruit intake.

It was found that those who ate a calorie restricted, high fiber/high plant based diet had far greater diversity in their GI bacterial populations, greater genetic diversity, less pathogenic bacteria and were overall, healthier. The reverse was true for the “SAD” microbiome. Bacterial species tended to be similar with a greater tendency for one bacterial strain to overrun others (aka: dybiosis).

Of importance, the microbiota samples used in this study were taken from those who had followed these dietary habits for more than 2 years. In other words, those bacterial populations were not created overnight.

Researchers then studied those mice, tracking those animals that were given select microbiomes. They then fed those mice given the “SAD” microbiome a dietary intake very similar to a calorie restricted, high vegetable intake diet. Overall, these mice had a weaker response to the dietary changes. There were some changes, but these were minimal- their microbiota did not diversify as much.

Interestingly enough, when the mice were allowed to cohabitate, mice with the healthier microbiomes seemed to share their bacteria with those mice with the less diversified microbiome. Researchers did note that mice, when living together, will eat each other’s feces which may have accounted for this bacterial pilgrimage however, we cannot forget (as noted earlier) that humans also share similar microbiomes when living together[xi].

There are some major take homes from this study. Although the microbiomes from those mice given the SAD microbiome did not change, as robustly, when fed an alternate diet, they did shift. It is absolutely possible to make-over one’s gut bacterial populations (and therefore significantly influence health). However, as with most things creating lasting health, it does not happen overnight. As noted above, it took more than 2 years, to create those microbiomes. This is similar to the premise that going to the gym and eating healthier for the month of January will not equal yearlong weight loss (which so many resolve to achieve on New Year’s).

This study also offers another explanation into why the SAD way of eating may impact so many Americans. This time, we see it reflected in the microbiome, which we now know has far reaching implications outside of the GI tract itself. Hypotheses into increasing mental illness, increasing cancer rates, autoimmune disorders, stress intolerance, etc. could all be made and theoretically related to the health of our bacterial make-up.

The more informed we become about our bacterial populations and how to manipulate them, the healthier we will be.

Some important tips:

• Get on a high quality probiotic as this is an important piece that will speed the process of microbiome diversity. Rotate these as to avoid GI habituation.
• Keep your dog or consider getting one (or pets in general) as it has been found that people living with animals have a more diversified microbiome. We share.
• Let your kids play in the dirt and if you garden, get your hands dirty. Get rid of the gloves. Soil is a beautiful earthly microbiome which has been gifted to us.
• Ditch the anti-bacterial soaps and hand sanitizers. These kill our good bacteria (remember, the microbiome is all over, not only in our GI tract).
• Wash your dishes by hand. Families without dishwashers have less allergies and immune sensitivities. This too, has been tracked to microbiome health and diversity.
• Make sure you are having at least 1 bowel movement daily. (And pay attention to your stools- I may be asking about them ;))
• If prescribed an antibiotic, make sure you actually have a bacterial infection and that that antibiotic is truly needed. Studies are confirming that after antibiotic treatment the bacterial composition in the gut never returns to its initial composition.
• And finally, work on food intake. Be highly mindful of food sources. As we have seen in the study at hand, this makes a difference. Rule of thumb- at least 5 cups of veggies a day (organic and avoid the “Dirty Dozen”), all animal protein/meat should be grass-fed/finished, avoid processed carbohydrates, and consume GI nourishing fats such as medium chain triglycerides (those found in coconut oil, high fat coconut milk, avocadoes, etc.)

The microbiome is simply another aspect of the terrain. A very important and in fact, foundational one. It’s make-over is the closest thing to a New Year, New You…

[i] Rabin, R. (2017) A Gut Makeover for the New Year. The New York Times Retrieved from: http://www.nytimes.com/2016/12/29/well/eat/a-gut-makeover-for-the-new-year.html?_r=1

[ii] Peter J. Turnbaugh¹, Ruth E. Ley¹, Michael A. Mahowald¹, Vincent Magrini², Elaine R. Mardis^1,2 & Jeffrey I. Gordon¹ An obesity-associated gut microbiome with increased capacity for energy harvest Nature 444, 1027-1031 (21 December 2006)

[iii]  Burcelin R. Regulation of Metabolism: A Cross Talk Between Gut Microbiota and Its Human Host. Physiology. 2012;27(5):300–307.

Musso G, Gambino R, Cassader M. Obesity, Diabetes, and Gut Microbiota The hygiene hypothesis expanded? Dia Care. 2010;33(10):2277–2284.

Turnbaugh PJ, Ley RE, Mahowald MA, Magrini V, Mardis ER, Gordon JI. An obesity-associated gut microbiome with increased capacity for energy harvest. Nature. 2006;444(7122):1027–131.

[iv] G Clarke, S Grenham, P Scully, P Fitzgerald, R D Moloney, F Shanahan, T G Dinan and J F Cryan. The microbiome-gut-brain axis during early life regulates the hippocampal serotonergic system in a sex-dependent manner. Mol Psychiatry, June 12, 2012 DOI: 10.1038/mp.2012.77

Linghong Zhou¹ and Jane A Foster Psychobiotics and the gut–brain axis: in the pursuit of happiness Neuropsychiatr Dis Treat. 2015; 11: 715–723.

[v] June L. Round & Sarkis K. Mazmanian The gut microbiota shapes intestinal immune responses during health and disease Nature Reviews Immunology 9, 313-323 (May 2009)

[vi] Scott J. Bultman^* Emerging roles of the microbiome in cancer Carcinogenesis. 2014 Feb; 35(2): 249–255.

[vii] Griffin, N. et al. (2017) Prior Dietary Practices and Connections to a Human Gut Microbial Metacommunity Alter Responses to Diet Interventions. Retrieved from: http://www.cell.com/cell-host-microbe/fulltext/S1931-3128(16)30517-0

[viii] Se Jin Song,¹ Christian Lauber,² Elizabeth K Costello,³ Catherine A Lozupone,^4,†b Gregory Humphrey,² Donna Berg-Lyons,² J Gregory Caporaso,^5,6 Dan Knights,^7,8 Jose C Clemente,^4†a Sara Nakielny,⁹ Jeffrey I Gordon,¹⁰ Noah Fierer,^1,2 and Rob Knight¹¹ Cohabiting family members share microbiota with one another and with their dogs. eLife. 2013; 2: e00458.

[ix] G Clarke, S Grenham, P Scully, P Fitzgerald, R D Moloney, F Shanahan, T G Dinan and J F Cryan. The microbiome-gut-brain axis during early life regulates the hippocampal serotonergic system in a sex-dependent manner. Mol Psychiatry, June 12, 2012 DOI: 10.1038/mp.2012.77

Linghong Zhou¹ and Jane A Foster Psychobiotics and the gut–brain axis: in the pursuit of happiness Neuropsychiatr Dis Treat. 2015; 11: 715–723.

[x] Griffin, N. et al. (2017) Prior Dietary Practices and Connections to a Human Gut Microbial Metacommunity Alter Responses to Diet Interventions. Retrieved from: http://www.cell.com/cell-host-microbe/fulltext/S1931-3128(16)30517-0

[xi] Se Jin Song,¹ Christian Lauber,² Elizabeth K Costello,³ Catherine A Lozupone,^4,†b Gregory Humphrey,² Donna Berg-Lyons,² J Gregory Caporaso,^5,6 Dan Knights,^7,8 Jose C Clemente,^4†a Sara Nakielny,⁹ Jeffrey I Gordon,¹⁰ Noah Fierer,^1,2 and Rob Knight¹¹ Cohabiting family members share microbiota with one another and with their dogs. eLife. 2013; 2: e00458.