Jan 28th, 2026

The Science Behind Your Gut - Why 38 Trillion Bacteria Control More Than You Think

During Maria's cancer treatment, nobody talked about her gut. Your body hosts roughly 38 trillion microorganisms that make compounds your body can't produce on its own, train your immune system, and talk directly to your brain. Here's what the science says — and what actually works.

By Fabio Lanzeri, CEO & Founder, LanFam Health

40+ years in pharmaceutical formulation and development. Fabio built ProleevaMax at his kitchen table after watching his wife Maria struggle with gut inflammation during cancer treatment.

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement regimen or making changes to your health routine.


During Maria's cancer treatment, nobody talked about her gut. Her doctors focused on where it had spread — including the lymph nodes, which metastasized — understandably. But some mornings, even lifting her arms to get dressed felt impossible. And it wasn't just the cancer doing that.

You Are an Ecosystem

Your body hosts roughly 38 trillion microorganisms — about as many as your own human cells 1. The microbial genes in your body outnumber your human genes 150 to 1.

Most of these microbes — about 95% — live in your large intestine. But they're not just sitting there. They make compounds your body can't produce on its own. They train your immune system. They talk directly to your brain.

Different microbial communities live across your body — mouth, skin, lungs, gut — each shaped by local conditions. Think of it like ecosystems on a planet. The rainforest works differently from the ocean floor, but both keep the whole thing running.

Your Gut Talks to Your Brain

About 95% of your body's serotonin — the chemical tied to mood, sleep, and focus — is made in your gut 3. Not your brain. Your gut.

Your gut and brain are connected through nerves, hormones, immune signals, and bacterial compounds. Probiotics can change how your brain processes emotions — visible on a brain scan 2.

During Maria's treatment, her mood crashed. Her sleep fell apart. Her concentration disappeared. At the time, nobody connected it to her gut. But when her gut bacteria were wiped out by treatment, it wasn't just digestion that suffered. It was everything.

What Throws It Off

Three things consistently disrupt gut bacteria in the research:

Antibiotics. A single course can cut gut bacterial diversity by 30% or more, and some species don't come back for months 4. Maria was on multiple courses during treatment. Each one was necessary. But nobody explained what those drugs were doing to the other 38 trillion organisms in her body.

Diet. Fiber is the primary fuel for beneficial gut bacteria. Diets low in fiber are linked to lower diversity. Ultra-processed foods have been associated with weakened gut barriers and increased swelling.

Chronic stress. Stress hormones change how your gut moves, reduce blood flow to the intestinal lining, and shift bacterial populations. The relationship runs both directions — gut swelling can itself promote anxiety 5. Maria lived that loop. The cancer caused stress. The stress worsened her gut. The worsening gut deepened the stress.

Signs Your Gut May Need Attention

Your body communicates constantly. Here's what to watch for:

  • Digestive: Bloating, irregular bowel movements, discomfort after meals
  • Whole-body: Persistent fatigue, brain fog (especially after eating), recurring infections, skin issues like acne or eczema
  • Metabolic: Unexplained weight changes, intense sugar cravings, blood sugar swings

No single symptom proves anything. But if you're seeing clusters of these after antibiotics, a major illness, or prolonged stress — pay attention.

What Actually Works

Here's what the research consistently supports:

Eat a wide variety of plants. People who ate 30+ different plants per week had significantly more diverse gut bacteria than those eating fewer than 10 6. Diversity builds resilience — a well-populated gut handles disruption better and recovers faster.

Add fermented foods. Ten weeks of eating more fermented foods — kimchi, yogurt, kefir, kombucha — increased gut diversity and reduced markers of body-wide swelling 7. Maria added these early in her recovery. It was the change she noticed first.

Manage stress. Movement, sleep, time outside, and basic stress practices all create conditions where beneficial bacteria do better. This gets overlooked in gut health conversations, but for Maria, it mattered as much as anything she took.

Consider targeted supplementation. Not all supplements are the same — results depend on specific ingredients, doses, and how they're delivered.* After decades of seeing products that threw ingredients together without understanding how they interact, I got focused on getting the combinations and dosages right.

What We're Still Learning

Researchers are exploring how specific bacteria influence everything from athletic performance to skin aging to cancer treatment response. The idea that you can intentionally shape your gut to support your health is a real shift in how medicine thinks about chronic conditions.

What's becoming clear: gut health and overall health are one system. No single diet, supplement, or habit is the whole answer. The evidence points to supporting the entire system — diverse food, fermented foods, stress management, and when appropriate, targeted supplementation.

The Gap

Modern medicine saved Maria's life. But the day-to-day rebuild — the gut recovery, the swelling management, the getting-back-to-feeling-like-herself part — that was where the system left us on our own.

That gap is what drove me back to the lab.

Why We Built ProleevaMax

I built ProleevaMax at our kitchen table because Maria was suffering and what was available wasn't enough.

The formula combines 13 natural ingredients selected for how they work together, not just individually:

  • L-Glutamine to help support the lining of your gut 8, paired with L-Serine to help support glutamine synthesis and glutathione production 910
  • Curcumin + Boswellia to help support a healthy inflammatory response
  • Piperine to help support absorption of key nutrients such as curcumin (turmeric) and resveratrol — so more of what you take can be put to work*

Each ingredient was chosen based on peer-reviewed evidence from our library of countless scientific citations, as well as consultation with a board of physicians and other molecular biologists in the pharmaceutical industry. The patent-pending formula is designed so the ingredients complement each other across multiple pathways.

Full disclosure: we sell this product. Our goal here is to explain the science honestly — including what the evidence supports and where more research is needed. Individual results vary, and supplementation is not a substitute for medical treatment.

If we wouldn't give it to our own, we won't make it. That's been our family's standard from the beginning.*


* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

References

  1. Sender R, Fuchs S, Milo R. "Revised Estimates for the Number of Human and Bacteria Cells in the Body." Cell. 2016;164(3):337-340. DOI: 10.1016/j.cell.2016.01.013
  2. Tillisch K, Labus J, Kilpatrick L, et al. "Consumption of Fermented Milk Product with Probiotic Modulates Brain Activity." Gastroenterology. 2013;144(7):1394-1401. DOI: 10.1053/j.gastro.2013.02.043
  3. Yano JM, Yu K, Donaldson GP, et al. "Indigenous Bacteria from the Gut Microbiota Regulate Host Serotonin Biosynthesis." Cell. 2015;161(2):264-276. DOI: 10.1016/j.cell.2015.02.047
  4. Dethlefsen L, Relman DA. "Incomplete Recovery and Individualized Responses of the Human Distal Gut Microbiota to Repeated Antibiotic Perturbation." PNAS. 2011;108(Suppl 1):4554-4561. DOI: 10.1073/pnas.1000087107
  5. Cryan JF, Dinan TG. "Mind-Altering Microorganisms: The Impact of the Gut Microbiota on Brain and Behaviour." Nature Reviews Neuroscience. 2012;13(10):701-712. DOI: 10.1038/nrn3346
  6. McDonald D, Hyde E, Debelius JW, et al. "American Gut: an Open Platform for Citizen Science Microbiome Research." mSystems. 2018;3(3):e00031-18. DOI: 10.1128/mSystems.00031-18
  7. Wastyk HC, Fragiadakis GK, Perelman D, et al. "Gut-Microbiota-Targeted Diets Modulate Human Immune Status." Cell. 2021;184(16):4137-4153. DOI: 10.1016/j.cell.2021.06.019
  8. Kim MH, Kim H. "The Roles of Glutamine in the Intestine and Its Implication in Intestinal Diseases." International Journal of Molecular Sciences. 2017;18(5):1051. DOI: 10.3390/ijms18051051
  9. Cruzat V, Macedo Rogero M, Noel Keane K, Curi R, Newsholme P. "Glutamine: Metabolism and Immune Function, Supplementation and Clinical Translation." Nutrients. 2018;10(11):1564. DOI: 10.3390/nu10111564
  10. de Koning TJ, Snell K, Duran M, Berger R, Poll-The BT, Surtees R. "L-Serine in Disease and Development." Biochemical Journal. 2003;371(Pt 3):653-661. DOI: 10.1042/BJ20021785
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