Body Composition
Protein Intake Calculator
A sound daily protein target is 1.2 to 1.6 g per kg of body weight as a floor, rising to 1.6 to 2.2 g/kg if you train hard to build or keep muscle (higher when in a calorie deficit). For a 70 kg person that is roughly 84 to 154 g a day, split across three or four meals.
Your daily protein target in grams, from your body weight. Two numbers, and they are not a contradiction: a floor you should hit every day, and a higher target if you are training hard to build or keep muscle.
Protein is the lever most people under-use
After 40, muscle is the tissue that protects your healthspan, and protein is half of how you keep it, the other half being resistance training. Most people eat far less than they think, and the shortfall shows up as muscle quietly lost over years. Hitting a protein floor is one of the highest-return, lowest-cost changes you can make. It matters most in two situations: in a fat-loss deficit, where protein defends the muscle you have, and on a GLP-1 medication, where appetite is suppressed and hitting the target becomes deliberate rather than automatic. If that is you, our GLP-1 muscle-loss calculator shows how much of your weight loss is likely muscle, and the GLP-1 Muscle Protocol turns the protein target into meals.
The floor and the target
Sources: Morton RW et al. 2018, Br J Sports Med (meta-analysis, gains maximise ~1.6 g/kg/day) and the ISSN Position Stand 2017 (build-and-maintain range 1.4 to 2.0 g/kg).
| Band | g per kg per day | Who it is for |
|---|---|---|
| Floor | 1.2–1.6 | Everyone, the daily baseline to hit consistently |
| Target | 1.6–2.2 | Training hard to build or keep muscle; the higher end in a deficit |
Want the full system, meals and all? The Muscle + Fat Loss Protocol turns these numbers into a Protein Playbook and a cookbook, structured across 12 weeks.
Protein intake, common questions
- How much protein do I need per day?
- Start with a floor of 1.2 to 1.6 grams per kilogram of body weight a day. That is the reachable baseline most people should hit, and it is far better ground than the intake most people drift to when protein is an afterthought. If you train hard to build or keep muscle, aim higher, at 1.6 to 2.2 g per kg, which is where the evidence clusters.
- Why is the target a range and not one number?
- Because the evidence supports a band, not a single figure. Morton and colleagues' 2018 meta-analysis found protein intakes around 1.6 g per kg per day maximised the muscle gained from resistance training, with little added benefit past about 2.2 g per kg. The International Society of Sports Nutrition places the build-and-maintain range at 1.4 to 2.0 g per kg. A floor you hit every day beats a ceiling you miss three days a week.
- Do I need more protein in a fat-loss deficit?
- The target sits at the higher end of the band. In a calorie deficit protein is doing double duty, defending the muscle you have while you lose fat, so more of it protects lean mass. This matters most after 40 and on appetite-suppressing medication like a GLP-1, where hitting the number becomes deliberate rather than automatic.
- Should I use my current weight or goal weight?
- For most people, current body weight is fine. But if you are carrying a lot of excess weight, basing the figure on current weight can overstate the target, so anchoring it to a goal weight is more reasonable. A dietitian can set this precisely. This is nutrition guidance, not medical advice; if you have a kidney concern, confirm your target with your doctor first.
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