Head-to-head comparison

Soy Protein Isolate vs Pea Protein Isolate: Which Has More Protein?

Soy Protein Isolate and Pea Protein Isolate show up in a lot of the same meal-planning conversations, and the honest comparison depends on which specific number you're optimizing for.

Soy Protein Isolate

90.0gprotein / 100g

375 cal · 1.0g fat · $$ · Quality 0.9

Pea Protein Isolate

80.0gprotein / 100g

375 cal · 6.0g fat · $$ · Quality 0.82

This isn't close. Soy Protein Isolate packs 90.0g of protein per 100g against Pea Protein Isolate's 80.0g — a 10.0g gap driven mostly by how concentrated or diluted each food naturally is.

On protein quality specifically, Soy Protein Isolate scores higher — one of the highest-quality plant proteins, near-complete on its own — compared to Pea Protein Isolate, which is DIAAS-adjusted, low in methionine, high in leucine for a plant source.

Cost is roughly comparable between the two ($$), so budget isn't the deciding factor here.

Soy Protein Isolate's typical serving also delivers more leucine (2450mg vs Pea Protein Isolate's 2100mg) — relevant if the goal is maximizing the muscle-protein-synthesis trigger per meal, not just total grams.

Verdict

If raw protein density is what you're optimizing for, Soy Protein Isolate wins clearly. Choose Pea Protein Isolate instead if its lower fat, cost, or prep time matters more to you than the extra grams.

Full nutrition comparison

Per 100gSoy Protein IsolatePea Protein Isolate
Protein90.0g80.0g
Calories375375
Fat1.0g6.0g
Carbs2.0g5.0g
Fiber1.5g4.0g
Quality score0.90.82
Relative cost$$$$
Prep time1 min1 min

Frequently asked

Which has more protein, soy protein isolate or pea protein isolate?

Soy Protein Isolate has 90.0g of protein per 100g compared to Pea Protein Isolate's 80.0g.

Which is lower in calories?

Pea Protein Isolate is lower in calories per 100g, at 375 vs the other's 375.