Gut Health and SPD: What You Need to Know

Hippocrates (aka- The Father of Medicine) famously said,

“All disease begins in the gut.”

Well, it’s taken modern medicine quite awhile to get on board, but research over the past two decades is finally catching up to what Hippocrates knew over 2000 years ago.

His assertion regarding the power of gut health has important implications for what’s going on with our kiddos who have neurological challenges like sensory processing disorder, autism, and ADHD, as well as other health conditions like allergies, asthma, and eczema.

Let’s break it down...

Stanford researchers Erica and Justin Sonnenburg are among the pioneers of what is now referred to as “one of the hottest areas of medical science:”
The human microbiome.

They’ve discovered that our bacterial inhabitants, or our microbiome, “touch all aspects of our biology (health), directly or indirectly.”

So, what exactly is the human microbiome?

Our bodies are made up of trillions of microbes- bacteria, viruses, and fungi. The human microbiome is the full collection of cells and genetic material of the different microbes that inhabit our bodies.

Now considered our second genome, there is growing evidence that it (the genes of our microbial inhabitants) has more of an influence on our overall health than our own genes. Given the fact that our microbiome’s genes outnumber the genes in our own genome by 100 to 1, this isn’t hard to believe.

What does the microbiome have to do with our guts and how exactly does it influence our physical and mental health?

The largest population of our microbes reside in our large intestine, or gut. These gut microbiota have many important jobs:

  • Assisting in digesting and absorbing foods
  • Producing vitamins and short-chain fatty acids
  • Killing potential pathogens
  • Maintaining a healthy weight
  • Regulating our immune system
  • Producing neurotransmitters such as serotonin and dopamine
  • Supporting detoxification
  • Regulating our hormones

These microbes are busy little guys!

You may have heard of the “gut-brain axis” or of the gut being called our “second brain.” These terms refer to a system of neurons called the enteric nervous system (ENS) that regulates the gastrointestinal tract.

The ENS is the only system in our bodies that can operate independently, without input from our central nervous system- hence the reason our gut is called our “second brain.”

Our “two brains” are constantly in communication, providing feedback to one another about things like how hungry we are, whether we’re feeling stressed, or if we’ve ingested a disease-causing microbe.

You can think of the “gut-brain axis” as an information superhighway. When you have a “gut feeling” or your “stomach drops” after hearing bad news, or you’re told to “check in with your gut”, it’s for good reason:

Your “second brain” processes sensory input first, then sends a message to your “first” brain.

The microbes in our gut directly influence the communication between our two brains.

When we have a balanced microbiome - when the good bacteria outnumber the bad - communication is clear and efficient. Our immune systems are robust, our neurotransmitters are plentiful, we absorb nutrients and digest food properly, our hormones are balanced, we have low inflammation, and both brains are happy.

Happy gut = happy brain = happy gut

When we have an imbalanced microbiome, a condition called “gut dysbiosis” (more bad bacteria than good), the superhighway of communication between our “two brains” goes haywire and all sorts of hell can break loose.

Think about the negative ramifications of communication breakdown in a marriage: poor communication is often the root cause of marital dysfunction. It’s the same with our two brains. When they can’t communicate effectively, it leads to physical, mental, and emotional dysfunction.

Possible Effects of Gut Dysbiosis (imbalanced microbiome):

  • Digestive issues (gas, bloating, stomach pain, constipation, diarrhea, reflux)
  • Allergies
  • Food sensitivities
  • Irritable Bowel Syndrome
  • Asthma
  • Autoimmune conditions
  • Chronic infections
  • Eczema
  • Acne
  • Joint and muscle pain
  • Headaches
  • Fatigue
  • Brain fog
  • ADHD
  • Hormone imbalance (weight gain, weight loss, poor sleep, food cravings, poor blood sugar regulation)
  • Autism
  • Depression
  • Sensory Processing Disorder

Who (besides Hippocrates) knew that these little microbes had such a profound influence on our overall health and well-being?!

So, what exactly is the link between gut health and SPD?

It’s well established that SPD and anxiety are buddies. Anxiety is correlated with the production of the neurotransmitter GABA, which has a calming, relaxing effect on our nervous system. It’s likely that kiddos who experience high anxiety are deficient in GABA.

What’s responsible for GABA production? You guessed it, your gut!

Healthy gut = sufficient GABA = low anxiety

Unhealthy gut (gut dysbiosis) = less GABA = high anxiety

Glutamate is another important neurotransmitter that’s produced by gut bacteria and is dependent on a healthy gut. It regulates over 50 percent of our nervous system, including our sensory systems, and is considered the most important neurotransmitter for normal brain function. It’s also the precursor to GABA production.

Glutamate is not messing around. It influences our cognition, learning, memory and our brain’s ability to effectively interpret sensory input.

Unhealthy gut = too much or too little glutamate = impaired sensory processing

The bottom line? A healthy gut is imperative for a healthy brain. If you have a child with sensory processing disorder, it’s likely that his gut is playing a role.

Next week, we’ll take a closer look at the signs and causes of gut dysbiosis in children and learn about the steps you can take to ensure your child has a healthy gut.

If you have any questions or comments, leave them below. The Sensory Mom readers and I would love to hear from you.


Who has the time to read dozens of books on SPD?

Download my FREE 25 page PDF guide to Understanding Sensory Processing Disorder.

Hi! I'm Cameron, mom of two incredible, "differently-wired" boys who have sensory processing challenges, wife of a nerdy surfer, mindfulness practitioner and Parenting Coach with master's degrees in education and psychology.