# Pea vs rice vs soy protein: which is best in South Africa?

Source: https://www.healthnews24.co.za/answers/pea-vs-rice-vs-soy-protein-south-africa/
Publisher: Healthnews24 (South Africa's supplement answer desk)
Updated: 2026-10-27

> Soy is the most complete single plant protein and has the best muscle evidence; pea is rich in lysine but low in methionine; rice is the reverse, low in lysine. A pea-and-rice blend covers both gaps, and at 30–40 g per serving any of them can support muscle. In South Africa pea isolate is cheapest: Faithful to Nature R148–R185 for 650 g (October 2026).

Key facts:
- Pea is low in methionine and rice is low in lysine, so a pea-and-rice blend balances both.
- Reid-McCann et al. (2025, 43 trials): soy showed no difference from animal protein for muscle mass; non-soy plant proteins gave smaller gains.
- Joy et al. (2013): 48 g of rice isolate matched 48 g of whey isolate over 8 weeks of training.
- FtN Pea Protein Isolate 650 g costs R148–R185 in South Africa (October 2026).

## Pea vs rice vs soy protein: which is best in South Africa?

For muscle, soy or a pea-and-rice blend. For price, pea isolate. No single plant protein matches whey on leucine or digestibility, but dose and blending close most of the gap.

| | Soy | Pea | Rice |
|---|---|---|---|
| Amino-acid limit | closest to complete | low in methionine | low in lysine |
| Protein quality (DIAAS, approximate ranking) | highest of the three (isolate) | lower; PDCAAS overstated it | lowest of the three |
| Muscle evidence | best: no pooled difference from animal protein for muscle mass (17 trials) | limited; trials small | one trial: 48 g matched whey over 8 weeks |
| Allergen | soy | none of the major allergens | none of the major allergens |
| South African supply in our data | not found as the main protein in any powder we priced | FtN, Raw Origins, USN, NPL, Biogen, 32Gi | Youthful Living (65% rice concentrate), 32Gi, NPL |

## What does the research say?

Whey and milk protein score highest on DIAAS, above soy isolate, which scores above pea protein concentrate (Mathai et al., 2017). A 2025 meta-analysis (Reid-McCann et al., 43 trials) found animal protein gave a small edge for muscle mass in adults under 60 (SMD 0.20) but no difference in strength, and the soy comparison alone showed no difference; non-soy plant proteins such as rice fared worse. Joy and colleagues (2013) gave 48 g of rice or whey isolate after training for 8 weeks and found similar body composition and performance, though the study had no non-supplemented control and was short.

Soy does not lower testosterone or "feminise" men at normal intakes; clinical evidence does not support that. See [is soy protein safe](/answers/is-soy-protein-safe-hormones-south-africa/).

## Why do blends make sense?

Pea supplies lysine and rice supplies methionine, so a blend balances them. South African blends include 32Gi (pea and rice isolates), Youthful Living (rice concentrate 65%, pea concentrate 17%, added L-lysine), NPL (pea isolate, rice concentrate, hemp, chickpea, pumpkin seed) and USN BlueLab (pea isolate with pumpkin and watermelon seed protein).

## What should you do in practice?

- Take 30–40 g of protein per serving, not 20–25 g, aiming for 2–3 g of leucine.
- Prefer a soy or blend product for building muscle; a single pea isolate such as FtN (R148–R185 for 650 g, 15 g protein per 20 g, unsweetened) is the budget choice.
- Watch heavy metals: Consumer Reports' 2025 US testing found plant powders averaged about nine times the lead of dairy-based ones. Rotate sources.
- Check allergens and shared-facility statements.

## Where can you compare products?

Use the [best vegan protein in South Africa](/answers/best-vegan-protein-powder-in-south-africa/) answer, [plant protein vs whey for muscle](/answers/plant-protein-vs-whey-for-muscle-south-africa/), [hemp vs pea protein](/answers/hemp-protein-vs-pea-protein/) and the [best plant protein](/best/best-plant-protein-south-africa/) ranking. Seek advice from a dietitian if you are pregnant, under 18 or have a soy or kidney concern.

## 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 |
| Raw Origins Yellow Pea Protein 80% (400 g) | 400 g | R169 (Faithful to Nature, 2026-10) | — | — | R42.25 | 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 |
| 32Gi Plant Based Protein Shake (720 g) | 720 g | R530 (Dis-Chem Living Fit, 2026-10) | — | R33.12 | R73.61 | erythritol and steviol glycosides |
| NPL Plant Protein (710 g) | 710 g | R440 (NPL shop (npl.za.com), 2026-10) | — | R36.34 | R61.97 | stevia and sucralose |
| Youthful Living Plant Based Protein (1 kg) | 1 kg | R519.99-R529.99 (Dis-Chem Living Fit, 2026-10) | — | — | R52.50 | stevia |

## Sources

- [Mathai, Liu & Stein 2017, DIAAS values for dairy and plant proteins vs PDCAAS (Br J Nutr) — AGRIS record](https://agris.fao.org/search/en/records/65de3cca0f3e94b9e5cc4b98)
- [Reid-McCann et al. 2025, Effect of plant versus animal protein on muscle mass, strength, physical performance and sarcopenia: systematic review and meta-analysis of RCTs (Nutrition Reviews 83(7))](https://pmc.ncbi.nlm.nih.gov/articles/PMC12166177/)
- [Joy et al. 2013, The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance (Nutrition Journal 12:86)](https://doi.org/10.1186/1475-2891-12-86)
- [OPB/NPR (Oct 2025): Consumer Reports finds lead in popular protein powders](https://www.opb.org/article/2025/10/16/consumer-reports-finds-lead-in-popular-protein-powders/)
- [Faithful to Nature: FtN Pea Protein Isolate Powder 650 g](https://www.faithful-to-nature.co.za/ftn-pea-protein-isolate-powder?smplid=116712)