appetite: what the trials say vs what this community says
Posting this as a discussion rather than a claim: appetite: what the trials say vs what this community says.
Tolerance to the gastric effect develops with continued exposure while the appetite effect largely persists. That single fact explains most of the "it settles but it still works" pattern the side-effect board reports.
Glucose-dependent insulin secretion is why hypoglycaemia risk is low as monotherapy: the effect scales with glycaemia rather than acting unconditionally.
Long half-life in this class comes from structural modification that promotes albumin binding and resists enzymatic degradation. Weekly dosing is a consequence of the molecule, not a convenience decision.
Not medical advice, obviously, and nothing here is approved for human use. One person with a spreadsheet.
best — the order this archive was captured in
The incretin effect is the observation that oral glucose provokes a larger insulin response than intravenous glucose at matched glycaemia, and the difference is mediated by gut hormones. That is the foundation the whole class sits on.
Left up and flaired Explainer. This is the standard of post the board was created for.
tolerance to the gastric effect develops, appetite effect largely persists
GLP-1 receptor agonism acts both peripherally — insulin secretion in a glucose-dependent way, slowed gastric emptying — and centrally, on appetite regulation. The central component is the better explanation for sustained intake reduction.
GIP is the arm people argue about because the biology is genuinely unsettled
Tried to build a mental model from mechanism alone and produced a confident prediction that the trial data flatly contradicted.
Yes. The discussion section is where the authors say what they actually think, and almost nobody here reads it.
What does the discussion section say about the limitation you are glossing?
Agreed that receptor distribution is the key to the side-effect map. It is not a mystery, it is anatomy.
receptor agonism is not the same as receptor activation in every tissue
Disagree. That is a preclinical finding in a rodent model and you are stating it as human pharmacology.
Not convinced by the linearity assumption. Dose-response in this class is not linear and the trials show it.
Read the primary paper after arguing about the summary for a fortnight. The discussion section said almost the opposite of what the thread had concluded.
Was completely wrong about the gastric emptying story in a thread here two years ago. Someone corrected me with a citation and I have not made that mistake since.
Was completely wrong about the gastric emptying story in a thread here two years ago.
Disagreeing with this specific inference — that is a preclinical result being read as human pharmacology.
Agreed that receptor distribution is the key to the side-effect map.
This is the concept everything else on this board is downstream of.
Citations welcome and expected here — this is the one board where "source?" is a compliment.
Spent an evening on the receptor distribution literature and the side-effect map suddenly stopped looking random.
Receptor expression in a tissue is necessary but not sufficient for an effect. You also need the agonist to reach it at relevant exposure, and that is where a lot of confident mechanism talk falls down.
dose response is not linear and nobody should assume it is
GIP receptor biology is genuinely unsettled — there is a live argument about agonism versus antagonism at the receptor — and the clinical results are robust regardless, which is an uncomfortable and interesting position.
albumin binding is most of the half-life story
GIP receptor biology is genuinely unsettled — there is a live argument about agonism versus antagonism at the receptor — and the clinical results are
Agreed — and it is why the central and peripheral stories are complementary rather than rival.
Small fix — it slows gastric emptying, it does not halt it, and the distinction matters for the mechanism you are proposing.
read the discussion section, that is where the honesty lives
the central appetite effect is doing more work than the gut effect
the peripheral and central stories are not in competition
The half-life explanation was the thing that made weekly dosing intuitive for me rather than arbitrary.
half-life is why these are weekly and not daily
- 1Agreed that receptor distribution is the key to the side-effect map. It is…9 comments in this branch · started by u/viktor_girard
- 2GIP receptor biology is genuinely unsettled — there is a live argument about…9 comments in this branch · started by u/asks_dumb_questions