// Guides & reference fasthq --docs · RSS
Precise, sourced notes on fasting phases, protocols, and the metabolic clock.
- Electrolytes and headaches while fastingWhy fasting headaches and fatigue happen, the role of sodium, potassium and magnesium, and what you can take without breaking your fast. Practical and sourced.
- How long until your body starts burning fat?You burn some fat within hours, but the real shift to fat as your main fuel comes as glycogen runs down. The fasted-state fat-burning timeline, with sources.
- How to start 16:8 fasting (your first week)A simple, no-drama way to begin 16:8 intermittent fasting: pick a window, push breakfast later, and what to expect day by day. Beginner-friendly and honest.
- What actually breaks a fast?Water, black coffee and plain tea are fine; calories and most sweeteners are not. What breaks a fast depends on your goal — a precise, sourced rundown.
- 16:8 vs 18:6 vs OMAD: which fasting protocol, and whenA clear comparison of 16:8, 18:6, and OMAD — the eating windows, the metabolic phases each reaches, who each suits, and how to step between them.
- Export your fasting data as CSV (because it's yours)Why data ownership matters for fasting logs, what FastHQ's CSV export contains, and how one-row-per-fast with ISO 8601 timestamps lets you analyze your own history.
- A fasting timer without gamification, streaks, or nag screensWhy streaks, badges, and notifications backfire for serious fasters — and what a fasting timer looks like when you strip all of it out. FastHQ's case for less.
- How many hours of fasting until ketosis?When ketosis typically begins during a fast, why the number ranges from roughly 12 to 18 hours, and what speeds it up or slows it down. A precise, sourced answer.
- How accurate are fasting-app phase trackers?Fasting phase trackers estimate your metabolic state from elapsed time alone. Here's what that can and can't tell you, where the numbers come from, and how to read them honestly.
- When does autophagy start during a fast?The honest answer to when autophagy begins when you fast: what the evidence actually shows, why the popular 16-hour figure is shakier than it looks, and how FastHQ models it.
- What metabolic phase am I in at 14 hours fasted?At 14 hours into a fast, most people are in late fasting / early gluconeogenesis: glycogen is running low and fat-burning is rising, but deep ketosis hasn't arrived. Here's the detail.