⏱ 6-minute read

Do you ever lie awake at night with your mind racing even though your body is exhausted?

Do you feel easily overwhelmed by things that you know, rationally, should not be overwhelming? Irritable in ways that surprise even you? Wound up at the end of the day when everything in you wants to wind down?

If any of that resonates, I want to introduce you to a neurotransmitter that does not get nearly the attention it deserves. A molecule that is quietly central to everything I have just described. And a gut connection that, once you understand it, will change the way you think about the racing thoughts, the overwhelm, and the nervous system's ability to find its way back to calm.

That neurotransmitter is GABA. Like serotonin and dopamine before it, its story begins not in your brain — but in your gut.

If you missed the previous newsletter on dopamine, you can find it here:

GABA — gamma-aminobutyric acid — is your brain and nervous system's primary inhibitory neurotransmitter. Where serotonin regulates mood and dopamine drives motivation, GABA's job is to slow things down. To put the brakes on. To signal to your neurons — you can stop firing now. It is safe to rest.

Think of your nervous system as an orchestra. Excitatory neurotransmitters like glutamate are the instruments playing — generating activity, alertness, response, and reaction. GABA is the conductor raising a hand to bring the volume down. Without adequate GABA the orchestra does not stop playing — it just gets louder, faster, and more chaotic.

When GABA is functioning well and present in adequate amounts, you can transition from activity to rest. You can let a stressful thought pass without it spiraling. You can fall asleep when your body is tired. You can handle the demands of your day without your nervous system treating each one as a five-alarm emergency.

When GABA is deficient or its receptors are not functioning properly, the nervous system loses its ability to inhibit itself. The result is the cluster of experiences that has become epidemic in modern life — chronic anxiety, racing thoughts, difficulty sleeping, emotional reactivity, muscle tension that never fully releases, and a nervous system that simply cannot find its way back to baseline.

Over the past several issues we have been building a framework together — the enteric nervous system as the second brain, enterochromaffin cells as the primary producers of gut serotonin, enteroendocrine cells as producers of gut dopamine. Today we add another layer to that framework.

GABA is produced in the gut — by both the cells lining the intestinal wall and directly by certain gut bacteria themselves. The gut contains GABA receptors throughout the enteric nervous system, and GABA signaling in the gut directly influences the signals sent upward through the vagus nerve to the brain.

This gut-GABA connection operates in both directions. A healthy gut with adequate GABA production and signaling supports parasympathetic nervous system function — the rest and digest state — and sends calming signals to the brain through the vagus nerve. A dysbiotic gut with impaired GABA production sends the opposite — distress signals that contribute to the anxious, hyperactivated nervous system state that so many people are living in chronically.

The landmark research by Bravo et al. (2011) that we referenced in the serotonin issue — showing that Lactobacillus rhamnosus administration produced measurable changes in GABA receptor expression in the brain — was specifically a GABA study. The bacteria were not influencing serotonin in that research. They were directly changing how the brain expressed GABA receptors — through the vagus nerve. When the vagus nerve was cut in the experimental animals, the effect disappeared entirely. The gut-to-brain GABA pathway is not theoretical. It has been experimentally confirmed at the mechanistic level.

GABA deficiency does not always announce itself as clinical anxiety. Often it shows up as a collection of experiences that feel like personality traits or lifestyle problems rather than a neurochemical one.

Signs that GABA may need support include difficulty falling or staying asleep despite feeling tired, a racing or busy mind that is hard to quiet, feeling easily overwhelmed by sensory input — noise, crowds, demands, and transitions, chronic muscle tension particularly in the jaw, neck, and shoulders, emotional reactivity that feels disproportionate to the trigger, difficulty relaxing even during downtime, craving alcohol or carbohydrates in the evening (both temporarily increase GABA activity — the body's attempt to self-medicate a deficiency), feeling anxious without a clear external cause, and a nervous system that feels perpetually stuck in high gear.

If several of these feel familiar — there are ways to support your GABA system.

1. Feed the bacteria that produce GABA directly. Certain Lactobacillus species — particularly Lactobacillus rhamnosus and Lactobacillus brevis — produce GABA directly through their own metabolic processes. Daily fermented foods — plain yogurt, kefir, and traditionally fermented kimchi and sauerkraut — deliver these strains to the gut consistently. A gut-brain axis targeted probiotic like Zenith, which includes evidence-based strains selected for their neurological and gut-brain signaling benefits, provides targeted support for the GABA-producing bacterial populations your nervous system most depends on.

2. Support GABA production with the right nutrients. GABA synthesis requires glutamate as its precursor — converted by an enzyme called glutamate decarboxylase (GAD) that requires vitamin B6 as a cofactor. Without adequate B6 this conversion is impaired and GABA production falls regardless of other factors. Food sources of B6 include grass-fed beef, pasture-raised poultry, wild-caught fish, potatoes, and bananas. Magnesium is equally critical — it directly activates GABA receptors and supports their sensitivity. The magnesium deficiency that is endemic in the modern population is one of the most direct and most prevalent drivers of GABA receptor dysfunction. Organixx Magnesium 7 — taken in the evening — supports GABA receptor function, nervous system wind-down, and the transition into deep restorative sleep in a way that no single-form magnesium supplement can match.

3. Activate the vagus nerve as a daily GABA practice. The vagus nerve is the primary transmission highway for gut-derived GABA signals reaching the brain. Every vagal activation practice we have discussed across previous issues — extended exhale breathing, humming and singing, cold water on the face, prayer and stillness — directly supports the gut-brain GABA communication pathway. Extended exhale breathing in particular has specific GABA-activating properties — the slow, deep exhale directly stimulates parasympathetic neurons that increase GABA activity in the brain. When the nervous system feels wound up and unable to quiet down, extended exhale breathing is your fastest accessible GABA intervention.

4. Remove the inputs that deplete GABA. Chronic stress, excess caffeine, chronic alcohol use (which temporarily increases GABA but dramatically depletes it over time through receptor downregulation), chronic sleep deprivation, and ultra-processed food diets all significantly impair GABA production and receptor function. Each of these removes either the bacterial populations that produce GABA, the nutritional cofactors that enable its synthesis, or the receptor sensitivity that determines how effective whatever GABA is produced actually is.

Because the need to be still — to release the tension and let the nervous system finally exhale — is not just a physiological need. It is a spiritual one.

We were not designed for the relentless pace of modern life. We were not designed to carry everything and never fully put any of it down. The nervous system that cannot find calm without help is not weak. It is depleted — by a world that has removed many of the natural inputs that keep GABA functioning and replaced them with inputs that systematically work against it.

Rest is available. The ability to quiet the noise is available.

"Come to me, all you who are weary and burdened, and I will give you rest. Take my yoke upon you and learn from me, for I am gentle and humble in heart, and you will find rest for your souls." — Matthew 11:28-29

That rest Jesus describes is not merely the absence of activity. It is the presence of peace. A nervous system at peace. A soul that has learned to release what it was never meant to carry alone.

That is what we are working toward. One step at a time. One meal, one breath, one moment of stillness at a time.

The path back to calm runs through your gut. Feed the bacteria. Activate the vagus nerve. Remove the depletors. Give your nervous system the consistent, repeated experience of safety and stillness that allows it to remember — this is what rest feels like.

Your body was designed for rest. It just needs the right building blocks to remember how.

With faith, science, and wellness,
Liz, The Wellness Nurse

Registered Nurse | Certified Mental Wellness Coach

P.S. Did any of this resonate with you? Do you recognize the can’t quiet down feeling? Hit reply and share- I read every response and want to hear from you.

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