Week 1

June 21 – June 27, 2026 · Days 1–7 · 7 entries

Days 1–7 of the One Year Fast project, written up day by day: three full fasting days in the week, what happened on each of them, and the weight, blood pressure and ketone readings recorded on those dates. Every figure shown here is measured on the day, not reconstructed later.

Day 1 · Sunday, June 21, 2026

Day 1 — Why I’m Fasting 3 Days a Week for a Full Year

Today marks the official start of my One Year Fast project. Over the next 365 days, I am committing to a rigorous weekly protocol—fasting 3 days every single week—to document the physical, metabolic, and emotional impacts of long-term structured fasting.

I am tracking every single metric completely out in the open, including my VO2 Max, DEXA scans, Resting Metabolic Rate (RMR), and routine blood work.

In this Day 1 video, I break down the exact baseline data I am starting with, how the fasting protocol will actually work, and why I am taking on this odd journey.

Day 2 · Monday, June 22, 2026

Day 2 — 48 Hours In: The Data, Data, Data

Welcome to Day 2 of the One Year Fast!

Day 3 · Tuesday, June 23, 2026

Day 3 — How I Use a Breath Ketone Meter to Track Ketosis

Welcome to Day 3 of the One Year Fast project. Today’s focus is on tracking the transition into ketosis using a breath ketone reader/analyzer. I break down exactly how this device works, how to read the measurements, and why monitoring breath acetone levels is a key part of the One Year Fast.

The goal of this project is to document a structured, year-long protocol—fasting 3 full days (72 hours total) every single week for 52 consecutive weeks—to observe the metabolic, physical, and cellular outcomes completely out in the open.

All baseline metrics, including my recent DEXA scan results, VO2 Max, and Resting Metabolic Rate (RMR), are fully detailed on the project website.

Day 4 · Wednesday, June 24, 2026

Day 4 — Reflecting on Week 1 and Breaking the Fast (Project moves forward)

Welcome to Day 4 of the One Year Fast project. In this video, I reflect on completing my very first week of the protocol, which involves fasting for 3 full days every single week for 52 consecutive weeks.

I also discuss how I approach breaking the fast as a vegetarian. I break down my choice for this week's first post-fast meal: a simple, nourishing barley and cabbage stew designed to gently reintroduce nutrients and ease digestion after an extended fasting window.

The purpose of this project is to document the metabolic, physical, and cellular outcomes of this structured journey completely out in the open. You can find all of my baseline health metrics, including my recent DEXA scan, VO2 Max, and Resting Metabolic Rate (RMR) results, on the website.

Day 5 · Thursday, June 25, 2026

Day 5 — Discussing my DEXA Scan

Welcome to Day 5 of the One Year Fast. In this video, I discuss my DEXA scan.

Fasting for three consecutive days a week requires balancing cellular renewal with the preservation of lean muscle tissue. I discuss how I am leveraging the science of autophagy over this year-long journey.

Day 6 · Friday, June 26, 2026

Day 6 — QuickUpdate: Feeling good & prepping my fasting essentials

A quick update today just to document the progress. Overall, I am feeling good and the momentum is building.

Tracking every single step of this protocol.

  • Day 6 Check-In: Keeping it quick for the record!
  • For Fasting Days: High-quality electrolytes to keep energy, hydration, and cellular balance on point.
  • For Eating Days: Premium amino acids to support recovery, maintain muscle integrity, and maximize my feeding windows.

Day 7 · Saturday, June 27, 2026

Day 7 — Fasting Week 1 Complete! Reflecting on My Journey & Mental Clarity

Week 1 is officially in the books! Hitting Day 7 of this one-year fast is a major milestone, and it’s giving me a chance to stop, reflect, and look back. In today’s video, I’m sharing a bit of my personal history, specifically my journey moving across the Atlantic.

During an extended fast, tracking physical metrics is only half the battle. I use these quiet moments of reverie and reflection to deeply gauge my emotional baseline and mental health. This journey is as much about shifting mindset and inner resilience as it is about cellular health.

Readings shown on each entry come straight from the health dashboard data logged on that date. The exact procedure, device and known limitations behind each measurement are documented on the methodology pages. For definitions of any term used above, see the fasting dictionary.

Written by Alfie Hammersham — founder of One Year Fast, who is fasting three full days a week for 52 consecutive weeks and publishing every biomarker openly. Not a doctor; every physiological claim on this site is referenced to published research, and lived experience is labelled as such.

Physiological claims on this page are cited to peer-reviewed studies; first-hand readings come from one subject and are labelled as personal experience. See the editorial & sourcing policy for how this is written, reviewed and corrected.

About the author · Editorial policy · Corrections & contact · Medical disclaimer