PeptideStack
5.2kquestions
20kanswers
220users

How much protein in grams do I need at 68 kg on 1,100 kcal a day?

Asked 11 Apr 2026Modified 3 months agoViewed 2.6k times
5

What I am working with: 68 kg · 1,100 kcal.

I have worked this out and I would like someone to find the error, because I suspect there is one.

My working so far, for the record, is below, and I am fairly sure the error is in the unit conversion rather than the algebra.

How many significant figures are actually justified here?

protein-intake
protein-intake

Protein targets in grams per kilogram, per-meal distribution and the leucine threshold, and the evidence for a higher intake specifically during…

53 questions
nutrition
nutrition

Eating on a suppressed appetite: hitting nutritional targets inside a small energy budget, micronutrient risk, meal structure, and what the trial…

92 questions
lean-mass
lean-mass

Lean body mass as measured rather than assumed: what DEXA, BIA and air-displacement plethysmography each actually estimate, the body-composition…

164 questions
shareeditfollowflag
HP
askedh_pergande86k25811 Apr 2026

3 Answers

Accepted answer first, then by votes
26

Accepted answer

Start with the arithmetic, because the answer to the practical question is usually a number and the number is usually achievable.

Food noise returning is not obviously tolerance. Receptor desensitisation is one hypothesis; a second is that the initial effect was partly novelty and partly the steep early deficit, and a third is that intake has drifted upward and the signal is being outcompeted rather than weakened. The three make different predictions about what a dose increase would do.

Protein target arithmetic

Body mass1.2 g/kg1.6 g/kg2.0 g/kgPer meal at 1.6 (÷3)
62 kg74 g99 g124 g33 g
74 kg89 g118 g148 g39 g
88 kg106 g141 g176 g47 g
103 kg124 g165 g206 g55 g
124 kg149 g198 g248 g66 g

At roughly 4 kcal per gram, 141 g of protein is about 564 kcal — a substantial fraction of a 900 kcal budget, which is the real constraint.

Mechanically, protein target, worked: at 88 kg, a target of 1.6 g/kg is 88 × 1.6 = 141 g per day. Spread across three eating occasions that is roughly 47 g each, and the leucine threshold for a maximal muscle protein synthetic response is met at around 2.5 to 3 g of leucine, which corresponds to roughly 30 to 40 g of a high-quality protein. So three meals at 40 g plus one 25 g snack gets you to 145 g and clears the per-meal threshold each time. On 900 kcal that leaves about 340 kcal for everything else, which is the actual constraint.

The evidence for a higher protein intake preserving lean mass during an energy deficit is reasonably strong in resistance-trained populations and weaker in sedentary ones, with the meta-analytic estimates supporting intakes in the region of 1.6 g/kg over lower intakes when training is present[1].

The plateau is arithmetic. Treat it as arithmetic and the response follows.

shareimprove this answerflag
DF
answered · acceptedDr_Colm_Fitzhenry85k24824 Apr 2026
Sponsored

PeptideMeter - Independent Peptide Analytics

Aggregated, published test results and vendor ratings built from submitted batches. Methodology stated, dataset browsable, no listing fees.

Browse results
22

The distinction that resolves this is between proportional loss and functional loss. Losing lean mass in proportion to total mass is what happens in every weight loss intervention. Losing function is not, and function is measurable.

Fibre at very low total intake is a trap. Soluble fibre needs water and motility to work; insoluble fibre adds bulk to a slow transit. At 900 kcal a day with delayed gastric emptying, an osmotic agent is more predictable than a bulking one, and adequate fluid is doing more work than either.

Cardio does not interfere with lean-mass retention at the volumes anyone here is doing; the interference effect in the literature appears at high concurrent volumes in trained athletes. What cardio does at a large deficit is add to the deficit, which is either the point or a problem depending on the objective.

Two resistance sessions a week and a protein target you actually hit will do more than any refinement beyond them.

shareimprove this answerflag
TO
answeredt_oyelaran41k382 May 2026
12

What the data supports is narrower than what gets recommended, so it is worth separating the two.

The minimum effective resistance-training dose in a deficit is lower than most programmes assume. Two sessions a week covering the major movement patterns, with loads taken close to failure, is sufficient to retain most of what would otherwise be lost. Volume beyond that adds recovery cost that a large energy deficit is poorly placed to pay.

Mechanically, hydration state moves a DEXA lean-mass figure directly, because the algorithm assigns water to the lean compartment. Scanning fasted, at the same time of day, before training and without a recent high-carbohydrate day is the difference between a comparable sequence and a noisy one. Bioelectrical impedance is far more sensitive to hydration again, which is why its trend is unusable at this timescale.

SURMOUNT-4 provides the cleanest maintenance-versus-withdrawal contrast available in the class, and it is the reference for any claim about what happens after stopping[1].

Measure strength as well as mass. It is cheaper, it is less noisy, and it is closer to what you actually care about.

shareimprove this answerflag
OF
answeredorla_ferriter47k3815 Apr 2026

Your answer

Ask PeptideStack is a static archive. Posting is closed, but the norms are worth stating: answer the question that was asked, show your working, cite the trial or the certificate, and say plainly where the evidence runs out.

Not medical advice. Research-use-only compounds are not approved for human use.