Skip to content

Glossary

Jargon, translated

Complicated language is how bad claims hide. Here is the vocabulary you need, written the way you'd explain it to a friend.

20 terms

Agonist
A molecule that switches a receptor on, mimicking the body's own signal.
Most GLP-1 medicines are agonists — they imitate a natural hormone rather than block it.
AMPK
A cellular energy sensor that switches on when fuel runs low.
Central to exercise and fasting biology, and to claims made for mitochondrial peptides.
Angiogenesis
Growing new blood vessels.
Essential for healing, and also exploited by tumours — which is why it appears in both benefit and risk arguments.
Antagonist
A molecule that blocks a receptor so the natural signal can't get through.
Blocking and activating the same receptor can both be therapeutic, depending on the disease.
Bioavailability
How much of a dose actually reaches your bloodstream in an active form.
Most peptides are destroyed by digestion, which is why so many are injected.
Confidence interval
The range of values the true effect plausibly sits within.
A wide interval crossing zero means the headline number could be nothing at all.
Conflict of interest
A financial or professional stake in the result of a study.
It doesn't automatically invalidate findings, but it changes how much benefit of the doubt is fair.
Half-life
How long it takes for half of a drug to clear from your system.
It drives dosing frequency. A days-long half-life means mistakes stay with you for days.
IGF-1
Insulin-like growth factor 1, the main downstream messenger of growth hormone.
It drives tissue growth, and higher levels are linked in epidemiology to some cancer risks — the core concern with GH-axis peptides.
Incretin
A gut hormone released after eating that helps manage blood sugar and appetite.
GLP-1 and GIP are incretins; the whole modern metabolic drug class is built on them.
Mechanistic evidence
Evidence about how something could work, from cells, receptors or models.
Necessary for developing drugs, insufficient for recommending them. Level 1, not Level 5.
mTOR
A cellular growth switch that turns on when nutrients are plentiful.
Growth and longevity often pull in opposite directions here. More growth is not always better.
Pharmacokinetics
What your body does to a drug: absorption, distribution, metabolism, excretion.
Without human pharmacokinetic data, nobody honestly knows what a dose is doing.
Phase 1 / 2 / 3
Phase 1 checks safety in small groups, Phase 2 looks for signals of effect, Phase 3 tests it properly at scale.
Most compounds sold online never completed Phase 1. That is not a technicality.
Placebo
An inactive treatment used for comparison.
Pain and recovery respond strongly to expectation, which is why uncontrolled injury reports mislead.
RCT
Randomised controlled trial — participants are assigned by chance to treatment or control.
Randomisation is what separates 'this works' from 'these people got better'.
Receptor
A protein lock on or in a cell that a specific molecular key fits.
Which receptors a peptide hits largely determines what it does — and what it does by accident.
Replication
Independent researchers repeating a study and getting the same answer.
One dramatic result is a hypothesis. A replicated result is knowledge.
Surrogate endpoint
A measurable stand-in for the outcome you actually care about.
Raising IGF-1 or shrinking a scan is not the same as living better or longer. Surrogates sometimes mislead.
Telomerase
An enzyme that rebuilds the protective caps on the ends of chromosomes.
A longevity target, but also reactivated in most cancers. Enthusiasm needs a caveat.