How much protein do you need to build muscle?
To build muscle, aim for about 1.6 g of protein per kg of body weight a day: meta-analysis of 49 trials found gains plateau around 1.62 g/kg (confidence range 1.03 to 2.20). For an 80 kg person that is about 128 g a day, with about 176 g (2.2 g/kg) a sensible ceiling. Two scoops of whey a day cost roughly R44 to R51 in South Africa (October 2026).
- Morton 2018 meta-analysis (49 RCTs, 1 863 people): muscle gains plateau around 1.62 g/kg/day (95% interval 1.03 to 2.20).
- Schoenfeld and Aragon 2018: about 0.4 g/kg per meal across at least four meals to reach 1.6 g/kg/day.
- Trommelen 2023: 100 g of milk protein gave a longer anabolic response than 25 g, so there is no hard per-meal cap.
- Two servings of USN BlueLab cost about R44 (R689 per kg, October 2026), delivering roughly 47 g protein.
How much protein do you need to build muscle?
Total daily protein plus resistance training is what builds muscle. The evidence level is strong.
What does the research say?
- Daily target. Morton and colleagues (BJSM, 2018) pooled 49 trials with 1 863 participants. Protein supplementation added about 0.30 kg of fat-free mass and 2.49 kg of one-rep-max strength on average, and benefits plateaued around 1.62 g/kg/day (95% interval 1.03 to 2.20).
- ISSN range. The ISSN position stand recommends 1.4 to 2.0 g/kg/day for most exercising people.
- Per meal. Schoenfeld and Aragon (2018) suggest about 0.4 g/kg per meal across at least four meals to reach 1.6 g/kg a day, and up to 0.55 g/kg per meal at 2.2 g/kg a day.
- No hard per-meal cap. A 2023 study (Trommelen) found 100 g of milk protein produced a longer anabolic response over 12 hours than 25 g, so a large meal is not wasted.
What does it look like in numbers?
| Body weight | 1.6 g/kg | 2.2 g/kg | Four meals at 0.4 g/kg |
|---|---|---|---|
| 60 kg | 96 g | 132 g | 24 g each |
| 75 kg | 120 g | 165 g | 30 g each |
| 90 kg | 144 g | 198 g | 36 g each |
Leucine matters too: aim for roughly 2 to 3 g per meal. About 25 g of whey provides around 2.5 to 3 g leucine, since whey is typically 10% to 11% leucine.
What does it cost in rand per day?
Using October 2026 prices and published servings:
| Powder | Per serving | Two servings |
|---|---|---|
| USN BlueLab 100% Whey (23.6 g protein per 32 g scoop) | about R22 | about R44 for roughly 47 g protein |
| USN Isozero (20 g protein per 23 g scoop) | about R25.70 | about R51 for 40 g protein |
Two scoops of BlueLab covers just over a third of an 80 kg lifter's 128 g target; the rest comes from food such as eggs, chicken, maas, biltong, fish and legumes.
Do you need isolate?
Not for muscle. Per gram, isolate and concentrate perform equally (isolate vs concentrate). ATP Fitness's Unflavoured Concentrate (R800 per kg) is a sweetener-free choice but publishes no protein per serving or third-party certification, so USN BlueLab is the better-documented value option.
What if you eat more than 2.2 g/kg?
Evidence shows little extra muscle benefit and extra cost. During a calorie deficit, higher intakes (2.3 to 3.1 g/kg) may help preserve lean mass in trained people, per the ISSN.
When should you see a professional?
If you have kidney or liver disease, are pregnant, are on medication or are under 18, speak to a doctor or dietitian before raising protein intake.
Where next?
See how much protein per day, when to take whey and creatine dosing. Training programme and sleep matter as much as the powder.
Products mentioned, with dated prices
| Product | Size | Price | R per 30 g protein | R per 100 g powder | Sweeteners |
|---|---|---|---|---|---|
| USN BlueLab 100% Whey Protein (1 kg) | 1 kg | R689USN shop (za.usn.global), Oct 2026 | R28.03 | R68.90 | not stated |
| USN Isozero Whey Protein Isolate (805 g) | 805 g | R899-R909.99USN shop (za.usn.global), Oct 2026 | R38.53 | R111.68 | not stated |
| ATP Fitness Unflavoured Whey Protein Concentrate | 1 kg | R800ATP Fitness shop, Oct 2026 | — | R80.00 | None |
ATP Fitness is a commercial partner of Healthnews24 and its products are featured on this site. Rankings follow our published method, and every pick, including ATP Fitness, shows its price maths and trade-offs. Read our disclosure.
Compare the options
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- Best Whey Isolate in South Africa 2026: 8 Tubs Compared
- Best Clean-Label Protein Powder in South Africa 2026: 7 Unsweetened Picks
- Best Mass Gainer in South Africa 2026: 8 Tubs Compared
Related questions
- How much protein do I need per day in South Africa?
- When is the best time to take whey protein?
- Whey isolate vs concentrate: which is better in South Africa?
- Do you really need protein powder in South Africa?
- How much creatine should you take per day?
Sources
- Morton et al. 2018, Protein supplementation and resistance-training-induced gains: systematic review, meta-analysis and meta-regression (BJSM)
- ISSN Position Stand: Protein and Exercise (Jäger et al., JISSN 2017)
- Schoenfeld & Aragon 2018, How much protein can the body use in a single meal for muscle-building? (JISSN)
- Trommelen et al. 2023, The anabolic response to protein ingestion during recovery from exercise has no upper limit (Cell Reports Medicine)
Educational information only, not medical advice. Speak to a doctor, pharmacist or registered dietitian before using supplements if you are pregnant or breastfeeding, under 18, taking medication, or living with kidney, liver or heart disease.
Cite this page: Healthnews24, “How much protein do you need to build muscle?”, updated 27 October 2026, https://www.healthnews24.co.za/answers/how-much-protein-to-build-muscle/. Plain-text version: /answers/how-much-protein-to-build-muscle.md