fuel. — the input
The inverted nutrition tracker, built for the UK: hit a protein floor with a suppressed appetite — not count yourself smaller. UK brands, barcode scan, saved meals and snap-a-meal AI.
What it does
Grams-to-go leads the day, with calories and a carbs/fat breakdown alongside. A target that sets itself from your body weight (1.6–2.2 g/kg), or set a fixed number.
Search is UK-first: British supermarkets and brands surface first, backed by a built-in UK food library and a million-plus packaged foods. Switch to a US region any time.
Search, scan a barcode, tap a recent or frequent food, or quick-add when you just know the protein. Save meals you eat often and log the whole thing in one tap.
Take a photo of your plate and an AI estimate returns the foods and macros for you to check and log.
A water tracker and one-tap favourites keep the basics quick. On semaglutide or tirzepatide in Optimise? Fuel switches to muscle-retention monitoring automatically.
On a GLP-1, Fuel tracks side effects — nausea, fatigue, appetite and the ones diet apps skip — with severity and a two-week pattern, right beside your food and weight. A personal log, not medical advice.
Days-on-target at a glance and a daily protein chart, with your protocol start dates overlaid.
Protein to go on your wrist, with the whole family at a glance. Part of the app from day one.
Family intelligence
Fuel × Optimise × Move
“Weight −6kg. Strength held. Protein averaged 142g/day.”
The sentence your clinician actually wants — and no standalone nutrition app can write it, because it takes all three datasets. That is the point of the family. Your grams-to-go also live on the combined "My Body — Today" home-screen widget — doses, workouts and protein on one glance, each row opening its own app.
A day with fuel.
152g today — computed from your current body weight at 1.8 g/kg. Step on any smart scale (Withings, Renpho, Garmin…) and it syncs through Apple Health — you never re-enter your weight; the family account already knows.
Greek yogurt + granola from the library: one tap, 18g banked. The ring moves.
On semaglutide, appetite quiet, lunch small. The banner doesn't nag about calories — it tells you a shake covers 25g of what's left.
Packaged food? Type three letters and the live database fills in the macros. Or quick-add “protein 30g” and move on.
Protein target hit ✓. Calories were visible if you wanted them; they were never the headline.
Days-on-target in the diary, the daily bars against your target line — and the dashed marker where the protocol began, explaining the whole shape.
Free vs Pro
Fuel Pro £3.99/mo or £29.99/yr — or everything in every app with My Body Pro, £49.99/yr, first week free.