Last updated: November 2026
Hold protein is a Calorie Planner setting that keeps your protein target steady when you change a day's calories, so the change comes out of carbs and fat instead. It's on by default because protein is what protects your muscle while you diet or build.
Most of the time you'll leave it on and never think about it. Here's what it does, and the few times it's worth turning off.
What happens when Hold protein is on
Lowering a day's calories takes them from carbs and fat. Raising them adds carbs and fat.
The Protein slider is greyed out.
A day can't go below the calories its protein needs. Each gram of protein is 4 calories, so a day holding 150 g of protein can't go under 600 calories without cutting protein. If you type a lower number, the Planner says Turn off Hold protein to go this low. If your other unlocked days can't lend enough to reach it, the line under the day reads Hold protein leaves no room.
What happens when Hold protein is off
You can edit Protein directly for that day.
Lowering calories can lower protein too. The line under the switch changes to Protein adjusts with calories.
Frequently asked questions about Hold protein
When should I turn Hold protein off? For a day you want much lower than usual, or when you want a different protein target for that day.
Do I have to turn it back on? No. It switches back on for every day each time you open the Planner.
Can the Planner raise my protein? Yes. After Match, Match all or a protein edit, the Planner checks your week. If your planned protein now averages under your target, it adds protein to your unlocked days from today on, up to your diet type's maximum. Calories don't move; the extra protein replaces carbs and fat.
How much protein does Carbon set? Carbon starts from your stats and goal and adjusts at each check-in. See What are macros? for how protein fits into your targets.
Move your calories however your week needs. Your protein stays put.