Discussion Guide — Chapter 15

Six prompts, with what to listen for. Each runs 10–20 minutes.

1. "These compounds do raise growth hormone. So what is everyone arguing about?"

Open with this. It invites the users in the room to participate without disclosing anything, and it puts the concession on the table before any criticism.

Listen for: students who reach for the surrogate/outcome distinction unprompted — that is the target behavior. Listen also for: the tell that a student is defending a position rather than analyzing one, which usually sounds like appeals to how the compound makes people feel, or to how many people use it. Do not correct that directly; ask what measurement would distinguish the two explanations. Common dead end: the discussion collapsing into whether the compounds are "legit," which is not a question the chapter's machinery can answer. Redirect to a specific claim with a population and an endpoint.

2. "Tesamorelin has an approval. Does that make the class proven or does it make the class's limits visible?"

Listen for: students holding both halves at once. The failure modes are symmetrical and equally common — one group takes the approval as validation of the class, the other dismisses it as irrelevant because the population is unusual. Push with: if the mechanism works, why did the sponsor not pursue general visceral fat reduction? Listen for: answers that engage with population-specific benefit-risk rather than assuming bad faith or regulatory obstruction. Case study 15.1 question 5 asks for the counter-argument to the chapter's inference, and a good discussion will surface it here first.

3. "Is 'it preserves your natural feedback loop' a safety feature?"

Listen for: the recognition that a negative feedback loop is an opponent. Students almost always arrive believing it is a guardrail, because that is how it is marketed and because "natural regulation" sounds protective. The move to reward is noticing that the same mechanism which limits the extreme is limiting the intended effect, so it cannot be claimed as a benefit selectively. Extension if the room is strong: ask what a compound would look like that genuinely did have a safety ceiling, and whether any exists in this class.

4. "An extended-duration analog: more natural, or less?"

The chapter's sharpest argument, and the one students find most satisfying once it lands. Listen for someone articulating the structural point unprompted — that the case for secretagogues rests on pulsatility and the most popular design abandons it. Then immediately test the other direction: ask whether the pituitary might impose burstiness on its own output regardless. A room that only produces the attack has not understood the section. Watch for: the GnRH over-extension appearing here; if it does, use it rather than shutting it down — ask the student what evidence would be needed to make their claim, and let them discover it is the same standard the book applies to the compound's advocates.

5. "Two years, randomized, IGF-1 restored to young-adult levels, no strength benefit. What do you do with that?"

The intellectual center of the chapter. Listen for students who treat this as a result about the inference rather than about MK-677 specifically. Listen for: the fluid-retention caveat on the fat-free mass finding — students who raise it unprompted have read carefully. Productive tension to introduce: was this trial a failure? It answered its question cleanly and reported an unwelcome result. Ask what it would have meant if the trial had never been run, and who would have benefited from that.

6. "Someone you care about is using one of these. What do you actually say?"

Close with this. It is exercise 15.33 in conversational form and it does something no analytical prompt can: it forces students to notice that being right is not the same as being useful.

Listen for: opening sentences. Most students draft something that leads with correction, and the teaching moment is asking them to predict how the other person would respond. Reward: answers that concede what is true first, that raise the glucose and insulin sensitivity question as a concrete and non-judgmental thing worth checking, that ask which molecule the person actually has, and that route to a clinician without making it sound like a rebuke. Name explicitly at the end: a chapter that only debunks loses the reader it most wants, and the same is true of a conversation.