The 72-Hour Fast

The Definitive Guide to Fasting — beginner to professional.

This is the book I wish someone had handed me when I started. Not a man in a lab coat lecturing you — a bloke who’s done it, got it wrong, got it right, and written down everything that actually held up.

It starts at the gentle on-ramp of 12:12 and climbs, rung by rung, to the gold standard of 72 hours. Stop at whichever rung suits your life. If 16:8 is your summit, brilliant — that’s a complete answer.

Kindle, paperback and hardcover. Bought it already? Claim your free PDF journal.

What’s inside

Thirty chapters in six parts, written so you can read it cover to cover or jump straight to the bit you need.

• Why any of this works — insulin, autophagy and ketones, in plain English. (Meet the bouncer on the door of a club called Your Cells.)
• The Ladder — seven rungs, from the overnight twelve to the 72, each with who it suits, how to do it, what you’ll feel and the common mistakes.
• Fast like you — fasting for women, for performance, for a metabolic reset, after the weight-loss jabs, and for the long game.
• The toolkit — what to drink, electrolytes done properly, breaking the fast, your first 72 hour by hour, and when not to fast at all.
• Troubleshooting — hunger waves, 3am wake-ups, training, plateaus, and the mother-in-law with the casserole dish.
• The reference shelf — the books worth reading next, a glossary in human English, a cheat card to screenshot and a week of log pages.

Hunger is a wave, not a gauge. It comes, it peaks, it passes.

From Chapter 22

Coming off the jabs?

Chapter 15 is for anyone stopping Ozempic, Wegovy or Mounjaro, or thinking about it. It covers what the drugs do, what the evidence says about stopping, and a four-phase plan for the months after. No sneering, no miracle claims. And nothing in it is a reason to come off a medicine: that’s a conversation for you and your doctor.

The free PDF journal

Buy the book in any format and My Fasting Journal is yours as a free PDF to print at home: twelve weeks of daily pages, weekly check-ins, and milestone pages for your First 24, 36, 48 and 72. Claim it here. I’m not in this to gouge you.

The book is for information, not medical advice. If you’re pregnant, breastfeeding, under 18, underweight, diabetic, on any prescription medication, or have a history of disordered eating, please read the Sensible Bit and talk to your doctor before you fast.

Greg x