Is plant protein as good as whey for building muscle in South Africa?

Q: Is plant protein as good as whey for building muscle in South Africa?

Plant protein can build muscle nearly as well as whey when you take enough: 30–40 g per serving, ideally a soy or pea-and-rice blend, and 1.6 g/kg a day in total. Pooled data show a small edge for animal protein on muscle mass in adults under 60 (SMD 0.20) and no difference in strength. In South Africa plant protein costs R8–R30 per 25 g of protein.

Close, if you manage dose and quality. Whey is rich in leucine, the amino acid that most strongly triggers muscle protein synthesis, and highly digestible. Most plant proteins have less leucine and one or more limiting amino acids, so you need a bit more of them.

What do meta-analyses find?

A 2025 meta-analysis (Reid-McCann et al., 43 randomised trials) found plant protein gave slightly less muscle mass than animal protein (SMD -0.20), mostly in adults under 60 and in non-soy sources, with no significant difference in strength or physical performance. Soy versus milk protein showed no difference for muscle mass across 17 trials.
Lim and colleagues (2021, Nutrients) found animal protein favoured lean mass mainly in adults under 50, with no overall difference in absolute lean mass or strength.
Morton et al. (2018) found protein supplements add muscle during resistance training, with benefits plateauing near 1.6 g/kg a day, regardless of source.
Joy et al. (2013) found 48 g of rice isolate matched 48 g of whey isolate over eight weeks.

Evidence level: moderate. Most trials are short, and training status, total protein and diet matter more than powder type.

How do you close the gap?

Lever	What to do
Dose	take about 30–40 g of protein per serving, not 20–25 g
Quality	choose soy or a pea-and-rice or multi-seed blend
Leucine	aim for 2–3 g per serving; ISSN gives 700–3 000 mg
Total	reach 1.6 g/kg a day from all sources
Contaminants	rotate sources; Consumer Reports found plant powders averaged about nine times the lead of dairy

What does it cost in South Africa?

Per 25 g of protein (October 2026): FtN Pea Protein Isolate R7.59–R9.49; USN BlueLab Plant R17–R20; 32Gi, Biogen and NPL plant blends R28–R30. Whey sits between about R15 (USN Hydrotech) and R42 (Myprotein Impact), with USN BlueLab Whey at about R23 and Isozero isolate near R32. Plant protein is not dearer: because you need a larger serving, check the cost of the serving you will actually use (vegan protein cost).

Who should choose which?

Vegan, dairy-allergic or lactose-sensitive: plant, with a blend and a bigger scoop (best vegan protein).
Flexible eater maximising muscle at the least effort: whey isolate or blend (best whey protein).
Vegan athletes should also review creatine, B12 and other supplements.

Healthnews24's best plant protein ranking applies the same method. Check with a dietitian if you are pregnant, under 18 or have kidney disease.

Products mentioned

Product	Size	Price (source, date)	Servings	R per 30 g protein	R per 100 g powder	Sweeteners
Faithful to Nature (FtN) Pea Protein Isolate Powder (650 g)	650 g	R148-R185 (Faithful to Nature, 2026-10)	—	R11.38	R28.46	none
USN BlueLab 100% Plant Based Protein (900 g)	900 g	R399-R474.99 (Dis-Chem Living Fit, 2026-10)	—	R24.54	R52.78	sucralose, acesulfame-K, steviol glycosides
NPL Plant Protein (710 g)	710 g	R440 (NPL shop (npl.za.com), 2026-10)	—	R36.34	R61.97	stevia and sucralose
USN BlueLab 100% Whey Protein (1 kg)	1 kg	R689 (USN shop (za.usn.global), 2026-10)	—	R28.03	R68.90	not stated
USN Isozero Whey Protein Isolate (805 g)	805 g	R899-R909.99 (USN shop (za.usn.global), 2026-10)	—	R38.53	R111.68	not stated

Educational information, 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. Prices were observed in October 2026 and are not offers.