The Aging Gut: A Lifelong Profile of Your Microbiome

The Urban Monk

As Robert Frost so eloquently put it many years ago, “nothing gold can stay.”

True as it was in Frost’s poem — “So Eden sank to grief, so dawn goes down to day” — the sentiment holds up against our experiences within the natural world all around us, as well as the natural world inside of us.

During the height of the pandemic, we were advised that our most vulnerable citizens would be the elderly and those with pre-existing conditions.

That’s because as you age, the systems in your body naturally wear down, and the accumulation of years of toxins and damage makes your immune system less viable and more vulnerable.

Knowing what we know about the immune system’s relationship with the gut, we could theorize that the gut’s microbial composition evolves in such a way that its immense power is diluted and not helpful for maintaining immune system efficacy.

Fortunately, we don’t have to theorize.

Through diligent and focused research, scientists have learned that typically, the microbiome goes through several cycles during the lifespan of a human being.

Although there are plenty of things we can do to alter and repair damaged intestinal joints, increase stomach acid production, and rebalance dysbiosis in the bacterial composition of our guts…

That work requires consistency, determination, testing, and cooperation with a specialist.

For the most part, if you’re not doing the work, the gut goes through several solid stages of development.

Let’s take a look…

Life in the Womb

This is the time when your body begins forming your gut’s microbiome, based on the behavior of your mother.

There is still a hardy debate about just how much the gut flora is affected by individual health decisions made by your mother, but we do know that they all have some effect.

For example, antibiotic use, a processed diet rather than a whole foods diet, and lifestyle choices of the mother all feed her (and baby’s) internal systems and create bacterial colonies.

For a long time, it was decided in popular science that the womb was a sterile environment.

However, recently there have been studies identifying bacterial communities in the placenta, amniotic fluid, and meconium.

Although more research is certainly required, it would appear that decisions made during pregnancy do affect the future composition of an infant’s microbiome.

Post Birth

It’s fairly well known among functional medical practitioners that a baby’s first few years of life can have a critical effect on the gut’s microbiome.

From the method of birth — vaginal or c-section — to the choice to breastfeed or use formula, and even whether or not the baby was born full-term or preterm, all play into the microbial make-up of their little, tiny guts.

When babies are born vaginally, they’re swabbed by the bacterial colonies in the vaginal canal and are thus exposed to the bacteria they need to form healthy and diverse gut flora.

(Even born via c-section, some doctors are beginning to swab the baby’s face with vaginal canal bacteria to keep them exposed.)

Breastfeeding has a similar effect on formulating the composition of the microbiome.

And being born full-term obviously gives a baby the full benefit of the longest exposure to the mother’s bacterial colonies as possible.

During the first two to three years of life, babies’ gut microbiomes are high in Firmicutes and Bacteroidetes. These bacterial families are ideal for helping the baby build strong defenses and gain weight.

Adult Life

After the incredibly formative first three years of life, fluctuations in the microbiome generally stabilize.

Your medication use, intake of processed foods, level of physical activity, quality and variety of whole foods eaten, and lifestyle all contribute to your baseline microbial composition.

That baseline is pretty tough to change — that’s why when we talk about healing the gut, we talk about doing work and making serious (if incremental) changes.

Building strong habits, keeping them for a long time, and getting rid of unhelpful ones as fast as possible is crucial to maintaining the “default setting” of your gut microbiome.

Old Age

As you advance in years, the microbial integrity of your digestive tract weakens.

The microbial population becomes less diverse, and resultant issues become likelier — like leaky gut syndrome, for example, or the overpopulation of harmful bacteria at the expense of beneficial bacteria.

Older people also tend to take more medication than younger, which indiscriminately kill bacteria in the gut, whether good or bad.

Lifestyle, exercise, and diet considerations should carry extra weight as we advance in years.

Since a lot of the research regarding the microbiome is fairly new, or rather, only made its way into popular discourse in the last few decades, there’s not too much we can do about the way we were raised or what affected our biome growth.

But as always, today is a new day, and a new chance to feed our gut what it really wants!

If you enjoyed these thoughts and think we’ve got something in common, I have a feeling you’re going to love the Urban Monk Academy. It’s the home of every class I teach — from Qi Gong to Life Gardening to Dream Yoga to Gut Health and even Tantra (I teach that live!) — and for two weeks, you can try it for free.