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Protein Intake Calculator (ISSN & ESPEN)

Determines individualized daily protein targets based on fitness goals, dietary pattern, and muscle protein synthesis (MPS) thresholds.

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Calculation

Sex
Primary Goal or Clinical Condition
Vegetarian or vegan diet (+10%)

Result

Target Daily Protein Intake
148 g/day

Recommended amount of pure protein per day

Acceptable Target Range
125 – 172 g/day

Lower and upper thresholds of effective intake

Specific Protein Ratio
1.90 g/kg

Grams of pure protein per 1 kg of body weight

Optimal Target Per Meal (4 meals)
37 g

20–40 g of protein provides an adequate leucine dose (~2.7–3 g) to stimulate muscle protein synthesis (leucine trigger)

Protein Caloric Contribution
592 kcal

Protein yields 4 kcal per 1 gram

Distribute protein evenly across 3–4 meals throughout the day, combining complete sources of essential amino acids.

The result updates as you change the fields. Your data never leaves the browser.

Only upon clicking, current data is sent to generate the PDF and is not stored.

How it is calculated

Grounded in clinical consensus statements from the International Society of Sports Nutrition (ISSN, 2017) and ESPEN. In patients with overweight (BMI > 28), Adjusted Body Weight (AdjBW) is applied to protect renal hemodynamics.

Formula

Maintenance: 1.0–1.4 g/kg; Muscle Gain: 1.6–2.2 g/kg; Fat Loss / Deficit: 2.0–2.4 g/kg; Endurance: 1.2–1.6 g/kg; Age 65+: 1.2–1.5 g/kg; CKD: 0.6–0.8 g/kg. Vegetarian: +10%.

Limits of the method

In chronic kidney disease (eGFR < 60 mL/min), protein prescriptions must be medically supervised by a nephrologist.

Sources of the method

  • Jäger R. et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr, 2017;14:20
  • Deutz N.E. et al. Protein intake and exercise for optimal muscle function with aging: recommendations from the ESPEN Expert Group. Clin Nutr, 2014;33(6):929–936
  • Morton R.W. et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on gains in muscle mass and strength in healthy adults. Br J Sports Med, 2018;52(6):376–384

This calculation is for reference only and is not medical advice, a diagnosis or a prescription. If you have a medical condition, are pregnant, take medication or have any doubts, discuss the result with a physician or a qualified nutrition professional.

How to Meet Your Daily Protein Target

1

Identify your target number

Enter your weight and goal. The calculator establishes your daily gram target and optimal per-meal serving size.

2

Aim for 25–40 g per meal

A single serving of 30 g protein (cottage cheese, 150 g chicken breast or fish) activates the leucine trigger for myofibrillar anabolism.

3

Diversify your protein sources

Combine animal proteins (eggs, poultry, fish, dairy) with wholesome plant-based sources (tofu, lentils, chickpeas, tempeh).

Sample Protein Targets for Different Objectives

Fat LossWeight 70 kg, cutting goal

Muscle preservation on a deficit

Target 2.2 g/kg = 154 g protein per day (616 kcal). Divided across 4 meals of 38–40 g each.

The high thermic effect of food (TEF 20–30%) boosts metabolic rate and curbs appetite.
Sarcopenia 65+Female 68 kg, age 68

Protecting muscle and bone in older adults

Target 1.3 g/kg = 88 g protein per day (replacing outdated 54 g based on 0.8 g/kg).

Maintains mobility, prevents hip fractures, and mitigates frailty.
HypertrophyMale 80 kg, resistance training

Muscle hypertrophy

Target 1.9 g/kg = 152 g protein (4 servings of 38 g).

Intakes exceeding 2.2 g/kg provide no additional muscle gains in drug-free athletes.

The myth of 'only 30 grams of protein absorbed per meal'

The body absorbs virtually all ingested protein; what differs is the rate of digestion. Larger meals (50–60 g) digest slower, sustaining amino acid release into the bloodstream over 5–7 hours. However, to maximize muscle protein synthesis (MPS) spikes, dividing daily intake into 3–5 servings remains optimal.

Why protein needs increase during a caloric deficit

In energy deficit, the body oxidizes muscle amino acids for hepatic gluconeogenesis. Elevating protein to 2.0–2.4 g/kg spares skeletal muscle tissue, ensuring weight loss is derived almost exclusively from adipose depots.

Clinical Protein Intake Guidelines (ISSN, ESPEN, KDIGO)

Category / ConditionRecommended Target (g/kg)Clinical Rationale
Sedentary adults (RDA)0.8 – 1.0 g/kgMinimum threshold to prevent deficiency
Optimal health & longevity1.2 – 1.4 g/kgSupports immune function, bone mineral density, and hormone balance
Resistance training & muscle gain1.6 – 2.2 g/kgMaximizes myofibrillar hypertrophy rate (Morton et al. 2018 meta-analysis)
Fat loss with caloric deficit2.0 – 2.4 g/kgPrevents muscle catabolism and controls hunger
Endurance athletes1.2 – 1.6 g/kgRepairs damaged fibers and drives mitochondrial biogenesis
Older adults (65+ years)1.2 – 1.5 g/kgOvercomes age-related anabolic resistance (ESPEN PROT-AGE)
Pregnancy (2nd–3rd trimester)1.2 – 1.5 g/kgFetal growth, placental expansion, and increased blood volume
CKD stages 3–4 (non-dialysis)0.6 – 0.8 g/kgReduces intraglomerular hypertension and uremic toxin accumulation

In obesity (BMI > 28), protein is calculated based on ideal or adjusted body weight (AdjBW), not total body weight.

Frequently asked questions

Does high protein intake harm kidneys in healthy individuals?

Extensive randomized controlled trials (including studies by Antonio et al. up to 3.3 g/kg/day) demonstrated that high-protein diets do not impair renal filtration in healthy individuals.

Should plant protein from grains and bread be counted?

Yes, all dietary protein contributes to total intake. However, vegetarians are advised to aim ~10% higher due to the lower bioavailability of certain plant sources.

What is the 'leucine threshold'?

Leucine is an essential branched-chain amino acid (BCAA) acting as the biochemical trigger for mTORC1 complex. Initiating muscle protein synthesis requires ~2.5–3 g of leucine in a single meal.

Is whey protein powder necessary?

No. Protein powders are simply convenient filtered dairy proteins. If you hit your target with whole foods (meat, fish, eggs, cottage cheese), supplements are unnecessary.

Does cooking alter the protein content of foods?

Boiling or baking denatures the quaternary protein structure, which actually aids digestive enzymatic breakdown. Total amino acid content remains unchanged.

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What next

Formula breakdowns, biomarker reference ranges and nutrition articles with cited sources are in the NutriFit knowledge base.

Go to the knowledge base