At a Glance
| Metric | ON Gold Standard Whey | Garden of Life Sport Plant Protein |
|---|---|---|
| Protein per scoop | 24g | 30g |
| Leucine per scoop | 2.7g | 2.9g ✅ |
| Calories | 120 cal | 170 cal |
| Fat | 1.5g | 4.5g |
| Carbohydrates | 3g | 7g |
| Protein type | WPI + WPC | Pea + Rice + Chia + Lentil |
| PDCAAS Score | ~1.0 (complete) | ~0.92 (engineered blend) |
| Digestive enzymes | Aminogen® added | 2 Billion CFU probiotic |
| Third-party cert | Informed Sport | NSF Certified for Sport |
| USDA Organic | No | Yes ✅ |
| Price per serving | $0.88 | $1.97 |
| Suitable for vegans | No | Yes ✅ |
What the Research Actually Shows
The long-standing assumption that whey protein is categorically superior to plant protein for muscle building has been challenged by more recent research. The early studies comparing plant and whey proteins used soy or single-source pea protein at doses with lower leucine content — and found whey superior. When leucine is equated, the gap largely disappears.
A 2015 RCT comparing whey vs rice protein supplementation in trained males at matched leucine doses found no significant difference in lean mass gains over 8 weeks. A 2021 meta-analysis of 18 RCTs found plant-based protein supplementation produced similar muscle hypertrophy to animal-based protein when protein doses were equalised.
The Leucine Engineering in Modern Plant Proteins
The best plant proteins in 2026 are engineered with leucine in mind. Garden of Life Sport combines pea (high leucine base), brown rice (methionine/cysteine), chia (complete EAA + omega-3), and lentil (lysine boost) — each source filling amino acid gaps in the others. The result is 2.9g leucine and a complete EAA profile comparable to whey.
Single-source plant proteins (plain pea protein, plain rice protein) remain leucine-limited. If you choose plant protein, choose a multi-source blend that explicitly discloses leucine content above 2.5g per scoop. Avoid products that don't disclose leucine.
When Plant Protein Wins
For vegans and plant-based athletes, there is no debate — well-engineered plant protein is the only appropriate choice. The debate is for omnivores.
For omnivores, plant protein is worth considering for dietary diversity (getting protein from different sources provides a broader range of phytonutrients), environmental footprint considerations, or if you experience GI discomfort from whey. The cost disadvantage ($1.97 vs $0.88/serving for our top picks) is the most significant barrier.
ON Gold Standard Whey wins — but Garden of Life Sport Plant Protein is better for some buyers
For muscle building in lactose-tolerant omnivores: whey protein wins on cost efficiency, leucine density, and absorption speed. For vegans, lactose-intolerant, or those prioritising food diversity: a well-engineered plant protein (Garden of Life Sport, Vega Sport) using a multi-source blend with 2.5g+ leucine per scoop is a legitimate alternative with comparable muscle outcomes at matched leucine doses.
Frequently Asked Questions
Yes — when total protein intake is adequate (1.6–2.2g/kg) and the plant protein delivers sufficient leucine (2.5g+ per serving). The research is clear: protein source matters less than total leucine and total daily protein. Use a high-quality multi-source plant protein like Garden of Life Sport or Vega Sport Premium.
Single-source pea protein has slightly lower leucine than whey per gram of protein (~7.8% vs ~10–11% leucine by amino acid weight). At matched leucine doses in RCTs, muscle gains are similar. In practice, you need slightly more pea protein per serving than whey to hit the leucine threshold — most quality products account for this by using 28–30g servings.
Soy is the most complete plant protein from an amino acid standpoint (PDCAAS of 1.0, equivalent to whey). The concern about phytoestrogens at typical supplement doses (25–30g/day) is not supported by clinical evidence — multiple meta-analyses find no hormonal effect in men at standard intakes. Soy is a legitimate protein source, though less popular than pea-based blends currently.
Garden of Life Sport Plant Protein (2.9g/scoop) and Vega Sport Premium (2.6g/scoop) are the leaders among commercial products. Look for products that explicitly disclose leucine content — brands hiding this number are usually hiding a low value.
Yes — plant-based protein production requires significantly less land, water, and generates lower greenhouse gas emissions than dairy-based whey. Pea protein in particular has one of the lowest environmental footprints of any protein supplement. For buyers where environmental impact matters, this is a genuine point in favour of plant protein.
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