How much protein per day when you're cutting?

The consensus range from meta-analyses of resistance-trained people is 1.6 to 2.2 grams of protein per kilogram of bodyweight per day — roughly 0.7 to 1 gram per pound. In a calorie deficit, the top of that range earns its keep, because protein’s job during a cut is not just building muscle. It’s stopping you from losing the muscle you have.

That’s the answer. The rest of this post is why the answer fails in practice, which has nothing to do with the number.

Why the top of the range during a cut

In a deficit, three things change at once: muscle protein synthesis gets harder to stimulate, appetite gets louder, and training quality wants to slide. Higher protein pushes back on all three. It spares lean mass while the scale drops, it’s the most satiating macronutrient per calorie, and it keeps the raw material available on the days training does go well.

There’s also a bookkeeping benefit nobody mentions: protein is the hardest macro to overeat by accident. A cut that anchors on a firm protein target and lets carbs and fat float inside the remaining calories is much harder to quietly ruin than one tracking calories alone.

Do the arithmetic once, in real food

At 82 kg (180 lb), the range is roughly 130 to 180 g per day. Write that down next to what 40 g actually looks like: a chicken breast, a tub of Greek yogurt with a scoop of whey, a can and a half of tuna. Now the day has shape — 170 g is four solid protein feedings, not an abstraction.

Distribution matters less than the internet says, but “less” isn’t “zero”: something in the region of 0.4 g/kg per meal, three to five times a day, is a sensible way to hit the total. If your total is right, though, you’ve captured most of what matters. Don’t let meal-timing perfectionism become the reason the total slips.

The exceptions worth knowing

• Very lean people cutting hard benefit from the top end, even slightly above it. The leaner you are, the more of any deficit wants to come from muscle.
• Heavier people can compute from goal weight rather than current weight — 2 g/kg of a 140 kg bodyweight prescribes a fairly silly amount of chicken.
• More than ~2.2 g/kg isn’t harmful for healthy people, it’s just spending calories that a cut could use elsewhere. In a deficit, those calories have opportunity cost.

Where protein targets actually die

Not at the planning stage — at the logging stage, three weeks in. Nobody fails at “eat 170 g of protein” on day two. They fail in week three when logging gets tedious, portions drift, and “about 40 g” quietly becomes 25. The gap between a written target and a logged reality is the entire game — the same gap we described for calories in why your TDEE calculator is wrong, and it compounds the same way: small logging errors add up.

This is where the tooling stops being a convenience and starts being the mechanism. Momentum makes the protein line a first-class target, not a footnote under calories: the barcode scanner and AI photo logging keep entry cheap enough to survive week three, the daily ring shows grams remaining rather than a percentage, and logging the meal earns the XP that keeps the streak alive — so the habit that hits the target is the same habit the game rewards.

The whole protocol, in four lines

1. Bodyweight in kg × 1.8 (or × 2 if you’re lean and cutting). That’s the daily target in grams.
2. Split it across three to five feedings that you actually like eating — sustainable beats optimal.
3. Log it every day, even the bad days. Especially the bad days.
4. Re-check the target only when your bodyweight changes meaningfully — it scales with you, not with the calendar.

The number takes thirty seconds to compute. The habit is the product.