How much protein when you are cutting
17 August 2026
Most macro arguments are not worth having. The split between carbs and fat matters far less than people think, and the best split is largely the one you can live with. Protein is the exception: it is the one macro worth being deliberate about while you are losing weight.
Why it matters more in a deficit
When you eat less than you burn, your body makes up the difference from stored energy. You would like that to be fat. Some of it can be lean tissue instead, and how much depends heavily on two things: whether you are giving your body a reason to keep muscle (resistance training), and whether you are giving it the raw material (protein).
This is not vanity. Muscle is metabolically active tissue — losing it lowers the burn rate you are trying to preserve, which makes every later stage of the cut harder. It also tends to make the outcome look worse: two people can lose the same 10 kg and end up looking completely different depending on what that 10 kg was.
There is a second, more immediate benefit. Protein is the most satiating macronutrient per calorie — it keeps you full longer than the equivalent calories of carbohydrate or fat. In a deficit, where hunger is the main reason plans fail, that is worth a great deal on its own.
Roughly how much
The commonly cited range for someone losing fat while training is around 1.6 to 2.2 grams per kilogram of bodyweight per day. For most people most of the time, landing anywhere in that band is fine, and the difference between 1.8 and 2.1 is not worth agonising over.
Two practical adjustments:
- If you carry a lot of fat, scaling to your total bodyweight overshoots. Using a target weight, or a lean-mass estimate, gives a more sensible figure.
- The steeper the deficit, and the leaner you already are, the more the higher end earns its place — that is when muscle is most at risk.
For a 90 kg person, that is broadly 145–200 g a day. It is more than most people eat without paying attention, and it is the single most useful thing to actually track.
Hitting it without it becoming a project
- Anchor each meal. Decide the protein first and build the rest of the plate around it. Three meals at 40 g each does most of the work.
- Breakfast is where it is usually lost. Cereal, toast and fruit is a near-zero-protein start, and it leaves an unrealistic amount to make up after lunch.
- Keep dense options to hand: Greek yoghurt, cottage cheese, eggs, tinned fish, chicken, tofu, milk, whey. Convenience is the deciding factor on a bad day.
- Do not fear the timing question. Total daily intake matters far more than distributing it perfectly, and “the anabolic window” has been considerably overstated.
What Cut does about it
Cut sets a protein target from your bodyweight alongside your calorie target, and shows both as you log. The macro breakdown flags when a day is protein-light while there is still time to do something about it, rather than reporting it as a failure at midnight.
It also keeps a fat floor rather than letting the maths drive fat to zero, and it does not moralise about carbohydrate. Protein is the deliberate one; the rest is preference.
None of this is medical advice, and individual needs vary — if you have kidney disease or another condition that affects protein intake, that is a conversation for your doctor rather than an app.