The Only 2 Peptides You Actually Need (Save Thousands Per Month)
Josh Holyfield has spent years deep in the world of peptides, and his core message cuts against the grain of what most people in that space are selling. He says you only need two peptides to get serious results, and those two are retatrutide and growth hormone.
Retatrutide, sometimes called "Reta" for short, is one of the newer compounds drawing attention in both medical research and performance circles. It works by targeting three hormone receptors at once, specifically GLP-1, GIP, and glucagon receptors, and that triple-action mechanism is what makes it different from older weight loss drugs like semaglutide. A phase two clinical trial published in the New England Journal of Medicine in 2023 found that retatrutide produced significant weight loss in participants over a 24-week period, with some people losing close to a quarter of their body weight, so the research backing it is not just anecdotal.
A 2025 review published in Biomolecules described retatrutide as a potential game changer in obesity pharmacotherapy because of how it combines appetite suppression with metabolic effects that older single-receptor drugs simply cannot match. The glucagon receptor piece of the puzzle is especially important because glucagon plays a role in how the body uses stored energy, and activating it alongside the other two receptors may accelerate fat loss beyond what appetite suppression alone can do. Holyfield is using it at what he calls a low dose, which suggests he is not chasing the maximum clinical weight loss numbers but rather using it as a tool to stay lean while supporting other goals.
The second compound he mentions is growth hormone, and he says he takes it at 4 to 6 international units per day, which is a dose that falls into a range many in the performance space consider moderate to moderately high. Growth hormone affects body composition in several ways, including promoting fat breakdown, supporting muscle tissue, and influencing how the body handles proteins and carbohydrates. Research published in a Polish medical journal as far back as 1999 found beneficial effects of growth hormone replacement therapy in elderly men, including improvements in body composition and physical capacity, so the science connecting growth hormone to physique changes has been around for decades.
The combination of a GLP-1 based drug and growth hormone is not random. GLP-1 receptor agonists tend to reduce appetite and slow how quickly food leaves the stomach, which makes it easier to stay in a calorie deficit, and growth hormone supports the preservation of lean tissue during that deficit so the weight being lost skews toward fat rather than muscle. These two compounds work on different pathways and essentially complement each other's weaknesses, because calorie restriction without growth hormone support can lead to muscle loss, and growth hormone alone without dietary control may not produce the dramatic fat loss results people are looking for.
Holyfield also emphasizes that testosterone optimization is a third piece of his protocol, though he does not classify it as a peptide. Research has consistently linked testosterone levels to muscle retention, recovery, energy, and mood, and a paper published in Expert Opinion on Pharmacotherapy noted that growth hormone and testosterone together affect body composition and cardiac function in ways that neither does alone. So his stack, while he calls it "just two peptides," is really a three-component system with retatrutide and growth hormone as the peptide-based elements and optimized testosterone as the hormonal foundation underneath both.
What makes his argument interesting from a practical standpoint is that he is actively telling people to spend less money in an industry where he has a financial stake. He names specific categories of compounds he is not using, including NAD, MOTS-c, and SS-31, which are mitochondrial peptides that have attracted a lot of excitement in longevity and biohacking communities. These compounds are being studied for their potential roles in cellular energy production, aging, and stress response, but Holyfield's point is that they are expensive and that their real-world effects may not be worth the cost compared to the foundational tools he is already using.
A systematic review published in Annals of Internal Medicine in 2025 looked at GLP-1 receptor agonists for weight loss in adults without diabetes and found that across multiple randomized controlled trials, these drugs produced meaningful and consistent weight loss, so the foundational evidence for the type of compound Holyfield is using as his base is solid. The evidence base for some of the more exotic mitochondrial peptides is considerably thinner, with much of the research still in early animal or in vitro stages, and that gap in evidence quality is part of what Holyfield is pointing to when he tells people to simplify.
The KISS principle he references from his military background is fundamentally about reliability and efficiency, and he is applying it to a world that tends toward complexity. People in the peptide and biohacking space often add more compounds hoping to layer more benefits, but each addition comes with cost, logistical complexity, and the potential for interactions that are harder to track. When you strip the protocol down to two well-researched compounds that address the two biggest levers in body composition, which are fat loss and muscle preservation, and pair them with optimized hormones and enough dietary protein, the approach becomes both simpler and easier to evaluate because there are fewer variables to manage.
Protein intake is another thing he mentions almost in passing but it carries real weight. Growth hormone's anabolic effects depend on having sufficient amino acid availability, and retatrutide's appetite suppression can make it harder for people to eat enough protein if they are not deliberate about it. So the practical challenge of his simple protocol is not complicated chemistry, it is making sure the basic nutritional inputs are in place to let the compounds do what they are designed to do.
His broader message is that the peptide industry profits from complexity and from people believing they need the next novel compound to get the results they want. And because he is someone who sells products in that space and is still telling people to simplify, the argument carries a different kind of weight than it would coming from someone outside the industry entirely.
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- Moiz A, Filion KB, Toutounchi H et al.. Efficacy and Safety of Glucagon-Like Peptide-1 Receptor Agonists for Weight Loss Among Adults Without Diabetes : A Systematic Review of Randomized Controlled Trials. Ann Intern Med. 2025. Source
- Katsi V, Koutsopoulos G, Fragoulis C et al.. Retatrutide-A Game Changer in Obesity Pharmacotherapy. Biomolecules. 2025. Source
- Jastreboff AM, Kaplan LM, Frías JP et al.. Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial. N Engl J Med. 2023. Source
- Kozakowski J, Adamkiewicz M, Krassowski J et al.. The beneficial effects of growth hormone replacement therapy on elderly men. Pol Merkur Lekarski. 1999. Source
- Agarwal M, Naghi J, Philip K et al.. Growth hormone and testosterone in heart failure therapy. Expert Opin Pharmacother. 2010. Source
- Dekker TJ. Editorial Commentary: Testosterone, Growth Hormone, and Vitamin D Supplementation Is Not Routinely Indicated for Orthopaedic Surgery Patients. Arthroscopy. 2025. Source
- Nguyen CT, Aaronson A, Morrissey RP et al.. Myths and truths of growth hormone and testosterone therapy in heart failure. Expert Rev Cardiovasc Ther. 2011. Source
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