Moral reflections on peptide world

“I need to lose 80 pounds. I’ve gained and lost the same ten pounds for the last five years. I cut out all alcohol two years ago. I’m still prediabetic. My blood pressure is bad. I’m having performance issues in the bedroom. I’m thinking about going on one of those new peptides, maybe even TRT (testosterone replacement therapy) but it feels like cheating. I’d be lying if I said I wasn’t at least a little motivated by vanity—I do want to look better; I also just want to be healthy. What do you think?”

A man in his fifties asked me this question. I appreciate and respect the fact that he feels tension here. I had a friend describe our Instagram-and-health-obsessed culture as “Peptide World.” We live in an increasingly image-oriented moment where the opportunities to compare your body to other bodies, worship youthfulness, and engage in medically risky behavior in the name of altering your appearance abound.

On the secular side, plausibility structures surrounding bodily modification are simple: The human body is merely an iteration on the eternal chain of evolutionary development. It is a machine, a technology, and engaging in experimental R&D will only serve the greater good. There is no oughtness to the human body; there is just what is and what could be. Resisting the limits of bodily life is a moral good; supraphysiologic levels of testosterone or reparative catalysts allow us to transcend previously conceived limits. Transhumanism or posthumanism, the wedding of technology and the human body, is the normatively assumed end for those who don’t understand our bodies, both individually and collectively, as designed or begotten.

Our hypersexualized and hyper-visual age is downstream from the rejection of worship of the one true God. When The Holy One isn’t revered, inevitably, the next-most-glorious being will be—the image of God, human bodies. When the thrust of the spirit of the age is to sexualize, optimize, compare, and transcend bodily limits, the church will inevitably be tempted to follow suit.

At the same time, pursuit of presentability, beauty, and aesthetic is not inherently vain. Vainglory, as the ancients called it, “is the excessive and disordered desire for recognition and approval from others,” writes Rebecca DeYoung in Glittering Vices. Stewardship of the body through discipline and responsibility is good; needing your physique to be noticed by others reveals a desire to be worshipped. Wanting to look nice as a side effect of health and bending the knee to vainglory are not the same thing.

If getting braces, haircuts, and wearing clothes that fit isn’t inherently vain (and I don’t believe they are), then neither is the desire to have a healthy body fat percentage. Similarly, if playing basketball instead of running 5Ks makes “getting in your cardio” easier, I’m not convinced that, in our world filled with poisons and addictive foods, that tirzepatide, retatrutide, and BPC 157 making it easier to function in health is necessarily a problem. Or, at least it’s not an isolated problem. Our modern world is a poisonous environment (think of microplastics, sedentary-based vocations, and air quality as examples) that may require extra-bodily support. People who live in Phoenix need sunscreen in a way that people who live in Seattle don’t; people who are pursuing health in 2026 may benefit from supplementary peptides in a way that people who were doing likewise in 1826 didn’t.

The effects of the curse of sin abound; sunburns, tweaked knees, and gut inflammation are stains on God’s good design of the body. The body has natural mechanisms to repair and resist decay; those, too, are marred by the ontological effects of sin. Peptides are short-chain amino acids; insulin, oxytocin, and endorphins are examples of ones that naturally occur in the body. The pains of aging are inevitable and time is undefeated, but we ought not refuse to make use of quality medical supports. Don’t let popular level misuse lead to a reactionary non-use of common grace blessings.

Like pain medications, there ought to be an appropriate distinction between medicinal and recreational use. Christians are rightly in favor of pain management and rightly against the dangerous escapism offered by non-clinical use of drugs.

I’m moved by the poem Dylan Thomas wrote to his aging father:

Do not go gentle into that good night / Old age should burn and rave at close of day / Rage, rage against the dying of the light.

I plan to live with energetic resistance to the decay of my body and hope other Christians do the same. Be sober about the temptations of transhumanism and vanity, but at the same time, rage against the dying of the light, and leverage the tools available as you seek to glorify God in your bodies.