Protein per kilo: where the number comes from

Every protein recommendation is expressed per kilogram of bodyweight, which is convenient and slightly wrong for some people. Here is where the numbers come from and how to adjust them for your situation.

Why per kilogram at all

Protein requirement scales with the amount of tissue that needs maintaining, and bodyweight is a cheap proxy for that. A 90 kg person has more muscle to feed than a 55 kg person, roughly in proportion.

It is a proxy rather than the thing itself, which is where the adjustments below come from.

The number and its shape

The useful finding from the meta-analytic work is not a single value but a curve. Benefit from additional protein rises steeply up to about 1.6 g per kilogram and then flattens.

Beyond that the confidence intervals widen and the average effect approaches zero. Which is why the common recommendation is a range rather than a point: 1.6 g per kilogram is where the benefit essentially plateaus, and 2.2 g is a comfortable upper bound that covers individual variation without being arbitrary.

Below 1.2 g per kilogram, people in a deficit start losing meaningfully more lean tissue, which is the practical floor for anyone training.

Adjusting for body fat

Here is the case where bodyweight misleads.

A 120 kg person with 40 per cent body fat has about 72 kg of lean mass. Setting a target of 2.0 g per kilogram of bodyweight gives 240 g of protein a day, which is unnecessary, expensive and hard to eat.

Two better approaches:

Use lean body mass. 2.2 to 2.5 g per kilogram of lean mass. For the example above, 158 to 180 g.

Use a realistic goal weight. If the goal is 85 kg, use 1.8 g per kilogram of that: 153 g.

Both land in a similar place and both are more sensible than the bodyweight figure. For people at a normal body composition the adjustment barely matters, which is why the simple version is usually fine.

Adjusting for the phase

Calorie deficit. Use the upper end, 1.8 to 2.2 g per kilogram. Energy is scarce, and the body is more inclined to use protein as fuel or break down muscle, which is the mechanism described in losing fat while keeping the muscle you built.

Maintenance. 1.6 g per kilogram is plenty.

Surplus, building muscle. 1.6 to 1.8 g per kilogram. Extra energy is available, so protein is less likely to be diverted, and there is no evidence that very high intakes accelerate gain.

Very lean and dieting hard. Towards 2.2 or a little above. The leaner you are, the more your body defends remaining tissue by drawing on muscle.

Age

Requirements rise with age rather than falling. Older adults show a weaker muscle-building response to a given dose of protein, so both the daily total and the per-meal amount need to be larger.

A reasonable target for adults over sixty who train is 1.6 to 2.0 g per kilogram, with at least 30 to 40 g per meal rather than 25. This is covered alongside the other changes in what changes about fat loss after 40.

Per meal, not just per day

The daily number is the headline; the per-meal number is how you actually hit it.

Roughly 0.3 to 0.4 g per kilogram per meal, three to five times a day, produces a better summed response than the same total in two large servings. For a 70 kg person that is 21 to 28 g per meal across five, or 26 to 35 across four.

The mechanism, and how much it actually matters, is in protein timing: what matters and what doesn't.

Rounding, and when to stop refining

The difference between 140 g and 150 g a day is not detectable by any measurement you have access to. The difference between 70 g and 140 g is enormous.

Pick a round number, aim at it, and spend your remaining attention on whether you actually hit it rather than on whether it should have been 3 g higher. Most people fail on execution, not on target selection.

Reaching it is the hard part

For someone eating a mixed Indian diet, 130 g of protein requires deliberate structure. The default day lands around 50 to 60 g.

Closing that gap is the real work, and it is covered in vegetarian protein worth the calories it costs and hitting your protein without a single scoop. The target itself takes thirty seconds to set.