Head-to-head comparison

Soy Protein Isolate vs Whey Protein Concentrate (WPC): Which Has More Protein?

Soy Protein Isolate and Whey Protein Concentrate (WPC) 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

Whey Protein Concentrate (WPC)

78.0gprotein / 100g

390 cal · 6.0g fat · $ · Quality 1.0

This isn't close. Soy Protein Isolate packs 90.0g of protein per 100g against Whey Protein Concentrate (WPC)'s 78.0g — a 12.0g gap driven mostly by how concentrated or diluted each food naturally is.

Whey Protein Concentrate (WPC) pulls ahead on protein quality specifically (highest DIAAS of any common protein source), even in categories where Soy Protein Isolate wins on raw grams.

Whey Protein Concentrate (WPC) is the more budget-friendly pick ($ vs $$ for Soy Protein Isolate), worth weighing if cost matters more than the other differences here.

If you're eating plant-based, this comparison is moot — Soy Protein Isolate fits, Whey Protein Concentrate (WPC) doesn't.

Verdict

The real deciding factor is dietary fit, not macros: choose Soy Protein Isolate if you need it to be plant-based, choose Whey Protein Concentrate (WPC) otherwise — the protein numbers are close enough that diet compatibility should lead.

Full nutrition comparison

Per 100gSoy Protein IsolateWhey Protein Concentrate (WPC)
Protein90.0g78.0g
Calories375390
Fat1.0g6.0g
Carbs2.0g8.0g
Fiber1.5g0.0g
Quality score0.91.0
Relative cost$$$
Prep time1 min1 min

Frequently asked

Which has more protein, soy protein isolate or whey protein concentrate (wpc)?

Soy Protein Isolate has 90.0g of protein per 100g compared to Whey Protein Concentrate (WPC)'s 78.0g.

Which is lower in calories?

Soy Protein Isolate is lower in calories per 100g, at 375 vs the other's 390.