There is a sentence I have been practicing for two years. I believe peptide therapy works. It sounds simple. It is not simple. In the culture of evidence-based medicine, a culture I was trained in, believe in, and have practiced inside for over two decades, saying you believe something that the evidence has not yet fully validated carries consequences. Raised eyebrows at conferences. The careful distance of colleagues. The quiet professional risk of being categorized alongside practitioners who sell supplements from their websites and promise reversal of disease through proprietary protocols.
I am not that physician. But I offer peptide therapy in my practice. And the results are making it increasingly difficult to stay silent in the way that professional caution has long required.
The state of the evidence for peptide therapy
Let me be precise about what I mean, because precision matters here. Peptides, short chains of amino acids that signal specific biological processes, are not a monolithic category. Some have robust clinical evidence. Body protection compound-157 (BPC-157), studied extensively in animal models for tissue repair and gut healing, has limited but accumulating human data. Thymosin alpha-1 has established immunomodulatory evidence from oncology and infectious disease research. CJC-1295 and ipamorelin, growth hormone secretagogues, have solid mechanistic data and a growing clinical literature in the context of age-related growth hormone decline. Epithalon has intriguing telomere data.
A 2025 review in PMC identified 36 preclinical studies and just one human trial on BPC-157, which is precisely the problem. The mechanism is real. The human evidence is thin. And yet the clinical results I am observing are consistent enough that silence no longer feels like scientific caution. It feels like avoidance. None of these compounds has been through the full Phase III randomized controlled trial process required for Food and Drug Administration (FDA) approval in the indications for which I use them. Some have been through Phase II trials. Some have extensive use histories in international medical systems, Russia, Eastern Europe, parts of Asia, that have not translated into American regulatory processes.
This is the honest state of the evidence. It is incomplete. It is not absent.
When traditional protocols plateau
I started incorporating peptides into my practice after observing something that I could not explain with my existing toolkit. Patients who had reached a plateau in their functional medicine protocols, optimal nutrition, sleep, exercise, hormonal balance, stress management, were still experiencing deficits. Tissue repair that was slower than expected. Immune dysregulation that persisted. Gut permeability that improved but never fully resolved. Growth hormone axes that were clinically suboptimal despite everything else being optimized. These are patients who had done the work. Who were adherent, motivated, educated. And they were stuck.
The first time I used BPC-157 in a patient with longstanding gut permeability and joint pain, I did it with the careful hedging of someone who was not yet sure they believed in the tool. I explained the evidence landscape honestly, the animal data, the theoretical mechanism, the absence of large human trials. I offered it as an experimental adjunct to a protocol that was already evidence-based in every other way. She came back six weeks later. The joint pain had diminished significantly. The gut symptoms, bloating, irregularity, the post-meal discomfort she had managed for years, were, she said, the best they had been in a decade. I am a physician. I do not extrapolate from single cases. But I have now used peptide protocols in enough patients, with enough consistency of response, that I can no longer explain it away as placebo or coincidence. Something is working. I do not fully know why. And I am afraid to say that publicly because medicine has not yet given me permission to.
The fear of speaking up
This fear, and I want to name it as fear, not professional discretion, is worth examining. It is the same fear that delayed the mainstream acceptance of low-carbohydrate diets for decades after the metabolic evidence was already compelling. The same fear that kept time-restricted eating on the fringe of clinical practice long after the circadian biology was well understood. The same fear that surrounds any intervention that works in the clinic before it is validated in the controlled trial. The problem with this fear is not that it protects patients. Genuine scientific rigor protects patients, and I support it unconditionally. The problem is when the fear of professional judgment causes physicians who are seeing consistent clinical results to stay silent, allowing a vacuum in which the only voices speaking about these therapies are the ones with the least clinical accountability.
If those of us who are using peptides carefully, selectively, and within a comprehensive integrative framework do not speak honestly about what we are observing, we cede the public conversation to those who are not being careful at all. So here is what I want to say, as clearly as I can. I do not claim that peptide therapy is proven in the way that metformin is proven, or that statins are proven. I do not use it as a first-line intervention or as a substitute for the lifestyle, nutritional, and hormonal foundations that remain the core of good functional medicine practice. I use it in specific patients, for specific purposes, after exhausting the evidence-based options, with full informed consent about the state of the evidence. And in those patients, I am seeing things that my training did not prepare me for. I do not know how to say this without the professional fear rising alongside it. I do not know how to reconcile the evidence I was taught to require with the clinical results I am witnessing. I am not sure I need to reconcile them yet. Maybe what I need to do first is simply say what is true.
Something is working. The evidence will catch up to the clinic. It usually does. I am just no longer willing to wait for permission to notice.
Shiv K. Goel is a board-certified internal medicine and functional medicine physician based in San Antonio, Texas, focused on integrative and root-cause approaches to health and longevity. He is the founder of Prime Vitality, a holistic wellness clinic, and TimeVitality.ai, an AI-driven platform for advanced health analysis. His clinical and educational work is also shared at drshivgoel.com.
Dr. Goel completed his internal medicine residency at Mount Sinai School of Medicine in New York and previously served as an assistant professor at Texas Tech University Health Science Center and as medical director at Methodist Specialty and Transplant Hospital and Metropolitan Methodist Hospital in San Antonio. He has served as a principal investigator at Mount Sinai Queens Hospital Medical Center and at V.M.M.C. and Safdarjung Hospital in New Delhi, with publications in the Canadian Journal of Cardiology and presentations at the American Thoracic Society International Conference.
He regularly publishes thought leadership on LinkedIn, Medium, and Substack, and hosts the Vitality Matrix with Dr. Goel channel on YouTube. He is currently writing Healing the Split Reconnecting Body Mind and Spirit in Modern Medicine.
