At a Glance
| Metric | ISO100 Hydrolyzed Whey | Impact Whey Protein |
|---|---|---|
| FitLab Score | 9.0/10 | 8.5/10 |
| Protein per scoop | 25g | 21g |
| Calories | 110 cal | 103 cal |
| Fat | 0.5g | 1.9g |
| Carbohydrates | 2g | 2g |
| Lactose | Zero (ultrafiltered) | Moderate (WPC-80) |
| Protein type | 100% Hydrolysed WPI | WPC-80 |
| Absorption speed | Fastest (~30 min) | Fast (~55 min) |
| Price per serving | $1.18 | $0.78 (sale) |
| Third-party cert | Informed Choice ✅ | None ✗ |
| Flavours | 12+ | 80+ |
Protein Type — Isolate vs Concentrate
The core difference is processing. MyProtein Impact Whey uses WPC-80 — whey protein concentrate at 80% protein purity. ISO100 uses 100% hydrolysed whey protein isolate — further filtered to 90%+ purity, then enzymatically hydrolysed into peptides.
In practical terms: ISO100 has significantly less fat (0.5g vs 1.9g per scoop), zero lactose vs moderate, and faster absorption. For someone tracking macros tightly or cutting for a competition, the cleaner macro profile matters. For someone in a bulk or casual training phase, the WPC macros are negligible.
Lactose — The Most Important Difference
If you have clinically confirmed lactose intolerance (or even just regular GI sensitivity to dairy), this comparison ends here: ISO100. The ultrafiltration process used in WPI production removes lactose completely. WPC-80 retains meaningful amounts.
The scale of global lactose intolerance makes this more important than most gym-goers realise. Estimates suggest 65% of the world population has reduced lactase activity. Most people compensate subconsciously — attributing GI discomfort to 'bad stomach days' rather than their WPC protein shake.
ISO100 Hydrolyzed Whey wins — but Impact Whey Protein is better for some buyers
ISO100 wins on protein quality, lactose content, absorption speed, and macro purity. Impact Whey wins on cost and flavour variety. The right choice depends entirely on your needs: lactose intolerant → ISO100 always. Budget-conscious, lactose tolerant → Impact Whey on sale.
Frequently Asked Questions
At matched protein doses, no — there is no significant difference in 12-week muscle mass gains between hydrolysed and standard WPI. The hydrolysis advantage is absorption speed, not total muscle built. The faster absorption (30 min vs 55 min peak) matters for twice-daily training athletes, not for those training once daily.
Generally no — Impact Whey is WPC-80 which retains significant lactose. Switch to ISO100, Isopure Zero Carb, or a plant protein like Garden of Life Sport which is completely dairy-free.
Fudge Brownie is widely considered the best chocolate protein flavour on the market at any price point. Gourmet Vanilla is the best all-rounder for mixing into coffee, oats, or baking. Birthday Cake is accurate but polarising.
MyProtein wins by a significant margin — 80+ vs 12+ flavours for ISO100. If flavour variety is important to you, Impact Whey has a clear advantage.
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