GLP-1 Knowledge Centre

Written and researched by Matt O’Brien, founder of Shift Some Timber.

This cornerstone guide explains the science behind GLP-1 medicines in plain English.

GLP-1, WITHOUT THE HYPE

Understand the medicine before the marketing.

What is approved, how it works, what differs and what the UK evidence actually says.

Compare medicinesPut established options side by side using the same questions.Explore What is emerging?Track oral medicines, new combinations and genuine regulatory progress.Explore Make a decisionClarify priorities, trade-offs and what to discuss with a professional.Explore

What is GLP-1?

GLP-1 is a natural gut hormone released after eating that helps regulate appetite, fullness and blood sugar.

What is GIP?

GIP is another incretin hormone. Tirzepatide acts on both GLP-1 and GIP receptors.

Hormones

Appetite is influenced by multiple hormones and brain pathways rather than willpower alone.

How they work

Modern medicines enhance incretin signalling to reduce hunger and improve satiety.

History

  • Orlistat
  • Saxenda
  • Wegovy
  • Mounjaro

The Future

Future therapies include triple agonists and newer oral medicines under development.

For one research example, read our retatrutide UK guide: trial results, safety and availability. It explains the evidence and uncertainty, not a purchase route.

Medication comparison overview

MedicineMechanism
MounjaroGIP + GLP-1
WegovyGLP-1
SaxendaGLP-1
OrlistatFat absorption inhibitor

This is the foundation page for future Decision Guides.

Looking at NHS access?

See which medicines sit in primary care, specialist services or phased commissioning.

NHS medication pathways →

Sources & evidence

Check the underlying guidance directly:

ALREADY USING TREATMENT?

Go to the thing you actually need.

Side effects, stopping, food and movement are already covered. My Timber keeps the useful bits together.

Side effects → Coming off → My Timber →