No guts, no glory.

No guts, no glory.

No guts, no glory.

Each of us has an internal community of bacteria located within us that we call the microbiome.

If the bacteria were simply swimming around digesting lettuce, this would be small beans.  But they’re doing much more than that.

Our gut instincts.

Bacteria are found nearly everywhere, both inside and outside our bodies.  The vast majority that make up our microbiome live in our gut (i.e., the small and large intestines), where most absorption of nutrients happens.  Comprised of upwards of 100 trillion organisms—about three pounds worth—our bacteria outnumber our human cells by a ratio of 10 to 1, scientists say.  We depend on them to help digest food, regulate our immune system, and protect us from disease-causing bacteria.

Here today, gone to Maui.

The human microbiome begins at birth and is ever-changing—as a result, there is no “normal” mix of bacteria.  Many strains are beneficial, while others can be quite harmful.  Diet and nutrition prominently affect the composition of “good vs. bad” bacteria, along with other factors:

  • The amount of bacteria we’re exposed to on a daily basis.
  • Dramatic changes in diet, such as going on a crash diet, can induce dramatic shifts in the microbiome within 24 hours.
  • Infections and use of antibiotics can cause significant and sometimes irreversible effects.
  • Age, level of stress, and the amount of regular exercise and sleep.

Meh—why should we care?

The function of our intestinal microbiome goes far beyond digestion.  Researchers at the NIH Human Microbiome Project are working to better understand the role of the microbiome in reducing the risk of disease, increasing resistance to infections, and bolstering the immune system.  According to Rasnik Singh, et al. (2017), proper diet and a healthy gut have been linked to mitigating many chronic conditions, such as:

  • Autoimmune diseases, arthritis, and inflammatory bowel disease
  • Poor brain health and cognitive decline
  • Heart disease and cancer
  • Obesity, diabetes, or metabolic induced hepatitis
  • Joint pain and swelling
  • Learning disabilities, such as ADHD and autism
  • Allergies, asthma, and psoriasis.

Additionally, changes in the gut microbiome are also believed to influence chemistry to the brain.  Attention stressed out students:  the “gut-brain connection” has been found to affect your ability to handle stress, anxiety, and depression.  It has also been linked to eating behaviors, energy levels, and sleep.  Now you know.

So, have we found the silver bullet?  Maybe, not yet.  Writing in Nature (2017), Medical Doctor Eamonn Quigley, former president of the American College of Gastroenterology, states that “with rare exceptions, identifying altered microbiota as causing disease seems premature at this time.”  Stay tuned, though—new DNA sequencing tools are being used to uncover how bacterial strains hinder or help our immune system fight disease.

You are what you eat.

Round tuitThe close relationship between what we eat and our microbiome suggests we can improve our overall health by modulating our diet and lifestyle (see:  Round tuit).  The problem is we plan to eat healthy but we fail to follow through (self-control trap*).  Here is what biologist Gina Rodriguez et al. (2017) and other experts (like your mom) recommend:

  • Ban the burger.  The Western Diet, characterized by high animal protein, saturated/trans fats, refined sugars, and low fiber foods has been found to lead to a marked decrease in numbers of total bacteria, predisposing consumers to many health problems.
  • Embrace the olive.  By contrast, the Mediterranean Diet, characterized by high fiber foods, red wine, moderate amounts of fish/poultry, and reduced dairy products, red meat, processed meat, and sweets, is highly regarded as a healthy balanced diet.
  • Shop smart.  Dietary professionals say these foods can help increase the level of good bacteria in your gut:
    • Fresh vegetables of all kinds, cereal, nuts, and whole pieces of fruit
    • Herbs, spices, and teas in moderation
    • Wild-caught fish, cage-free eggs, pasture-raised meat
    • Healthy fats (e.g., coconut and extra virgin olive oil, nuts/seeds)
    • Ancient grains and legumes/beans—more fiber is good!
    • Red wine and dark chocolate/cocoa in moderation.
  • The case for probiotics.  It is likely that probiotics help promote a healthy balance of bacteria and the gigantic probiotics and dieting-book industries certainly want you to think that.  Yet, critics point out that research is still in its infancy and human studies are extremely limited.  So, don’t go overboard.
  • Other stuff.  Avoid antibiotics if possible, reduce stress, and exercise more.  Also, consider adding supplements, such as omega fish oil.

Researchers are examining how tweaking our diets, lifestyles, and environments can shape the bacterial ecosystems in our bodies.  Clearly, evidence is mounting that promoting a healthy gut microbiome is critical to overall human health and longevity.  The bottom line:  pay more attention to what you eat (and always listen to your mom).


Life expectancy would grow by leaps and bounds if green
vegetables smelled as good as bacon.
~ Doug Larson, American journalist


* Questionable beliefs can “trap” our better judgment, leading to poor decisions and unintended consequences.  In the self-control trap, we fail to follow through on our intentions, often sacrificing that which is in our long-term self-interest.  Learn more about this, and other traps, in the Young Person’s Guide to Wisdom, Power, and Life Success.


I love taking my message directly to students and groups of young persons!  If you would like me to speak at your school, not-for-profit, or corporate event, please use the Contact Form and enter “Speaker” in the subject line.  We’ll work out the details.  ~ Brian


Image credit: “Happy couple in love with cereals fruit and coffee” by Federico Marsicano, licensed from 123rf.com (2017).