Losing weight and GLP-1

How much protein should I eat to lose weight?

By GyroscopeUpdated November 14, 20267 sources

Eat the typical 1.2 to 1.6 g of protein per kg a day, counted from today’s weight, or from nearer your goal if you have more than a fifth of your weight to lose. That’s 110 to 145 g at 200 lb, and 125 to 165 g at 250 lb aiming for 180. Lean people who lift hard on a tough diet need 2.3 to 3.1 g per kg of lean mass. The Gyroscope app personalizes yours.

Most diets are built around cutting something: carbs, fat, sugar, meals. Protein gets cut along with everything else, because eating less food means eating less of all of it. That’s the problem. When you eat less than you burn, the body makes up the gap from fat and from muscle, and protein is one of the two things that tilt it toward fat.

We’d do three things. Hit your range every day, counted from the right weight. Put protein first at each meal, so it’s the part that survives when portions shrink. And lift weights at least twice a week, because the protein needs a reason to stay as muscle.

Think of a diet as a sale where the body sells off a bit of everything. Protein and lifting put a “not for sale” sign on the muscle.

Your range while losing

The top two rows count from today’s weight because their loss is under a fifth. The bottom two count from the goal plus a fifth of today’s weight. Goal weight or current weight has the reasoning, and the daily range calculator does the math.

What protein does on a diet

The 2025 to 2030 US guidelines rest their range on a review of 30 trials, mostly in adults losing weight. People on 1.2 to 1.6 g per kg lost about 3 lb (1.3 kg) more fat and kept about 1.8 lb (0.8 kg) more lean mass than people on 0.8 to 1.0, and no trial found harm.

How much lean mass goes depends a lot on the diet. In the body-scan study inside the SURMOUNT-1 tirzepatide trial, about a quarter of the weight people lost was lean mass, and that was true in the placebo group too. Losing weight takes some lean mass with it, drug or no drug.

In a 2016 trial, 40 young men ate 40% fewer calories for four weeks and trained hard six days a week. On 2.4 g of protein per kg, they gained 2.6 lb (1.2 kg) of lean mass and lost 10.6 lb (4.8 kg) of fat. On 1.2 g they gained 0.2 lb (0.1 kg) of lean mass and lost 7.7 lb (3.5 kg) of fat. A 2014 review of six studies found the same thing for lean lifters on a diet, and put them at 2.3 to 3.1 g per kg of lean mass. For a 180 lb man at 15% bodyfat, that’s about 160 to 215 g.

Protein and hunger

Protein helps a little with the calories too. Digesting it uses 20 to 30% of its own calories, against 5 to 10% for carbs and 0 to 3% for fat. And in a 22-person trial, cutting protein from 15% to 10% of calories made people eat 12% more, mostly in snacks. Raising it to 25% didn’t make them eat less, though. Protein helps you avoid overeating when it’s low, and it isn’t an appetite switch. See the myth that more protein makes you eat less.

How to eat it on fewer calories

On a diet, protein takes up a bigger share of a smaller plate. 120 g of protein is 480 calories, about a third of a 1,500 calorie day. Foods with 15 g or more of protein per 100 calories make that fit, like chicken breast, canned tuna, shrimp, nonfat Greek yogurt and 1% cottage cheese. See why you can’t hit your protein on 1,200 calories and the ranked list in protein per calorie.

To check that what you’re losing is fat, use bodyfat.guide’s fat or muscle check and its answer on losing muscle in a calorie deficit. On a GLP-1, see protein on Ozempic or Mounjaro.