Overview
Cost-per-gram of verified protein is the number that actually matters, and Impact Whey Isolate wins it by a wide margin. MyProtein's manufacturing scale lets them run a 90%+ protein-by-weight isolate at a price point that undercuts nearly everything else on this list — without cutting the corner that usually comes with 'cheap': third-party verification. Informed Sport certification means every batch is independently checked for banned substance contamination, which is not something you typically find at this price tier.
The best cost-per-gram isolate on the market and it's not particularly close. Our lab confirmed what MyProtein claims: 90%+ protein by dry weight with fat and lactose content that rivals products priced twice as high. Informed Sport certification means every production batch is independently verified for WADA-banned substance contamination — essential for competitive athletes who need more than a brand's word. Cold-water mixability and flavour breadth are both industry-leading.
Buy It If
You're optimizing a monthly supplement budget without wanting to gamble on an unverified budget brand. This is the rare case where the cheapest option in a category is also one of the most rigorously checked.
Skip It If
You need the absolute fastest absorption for a tight pre-competition window — R1's hydrolysate fraction edges this out on raw speed, though the difference is marginal for anyone outside competitive timelines.
Pros & Cons
Pros
- Best cost-per-gram of any isolate tested
- Informed Sport batch certified
- 100+ flavour options
- Exceptional cold-water mixability
Cons
- Leucine marginally below 2.5g threshold
- UK-based — longer shipping for US buyers
- Quality variance between flavour SKUs
Nutrition Facts
Per single scoop (28g serving):
Nutrition Facts
Protein Quality
Impact Whey Isolate is MyProtein's flagship isolate line, produced at the company's own manufacturing facility in Wales — a vertically integrated setup that removes several margin layers most competitors pay for (co-packing fees, third-party manufacturing markups) and passes that savings directly into shelf price. MyProtein is one of the largest sports nutrition manufacturers in Europe, and Impact Whey Isolate is the product line that built that scale.
Bioavailability
PDCAAS 1.0, DIAAS ~1.06. High plasma leucine spike confirmed within 60 minutes. Rapid gastric emptying profile typical of high-purity isolates.
Filtration Process
Cold-process cross-flow ultrafiltration. Minimises denaturation and partially retains immunoglobulin and lactoferrin bioactive fractions.
Leucine Yield
~2.45g — marginally below the 2.5g mTORC1 threshold. Easily bridged by pairing with leucine-rich whole foods at the same meal.
Amino Spiking
Clean across all batches. Informed Sport independently corroborates absence of non-protein nitrogen boosters on every production run.
Ingredient Breakdown
The formulation is a straightforward whey protein isolate base with flavoring, sweetener (sucralose or stevia depending on flavor), and a small amount of soy lecithin for mixability. There's no concentrate blended in to cut cost — a common practice among budget brands that isn't happening here despite the aggressive pricing.
Whey Protein (Isolate/Concentrate/Hydrolysate)
Lecithin (Soy or Sunflower)
Artificial & Natural Flavors
Taste & Mixability
Chocolate Smooth mixes well in a standard shaker bottle, with a texture that's slightly thinner than concentrate-based competitors due to the higher isolate percentage removing more fat. Flavor intensity varies noticeably by SKU — the fruit flavors (like Strawberry Cream) test sweeter and more artificial than the chocolate and vanilla lines in our panel testing.
Digestion
Impact Whey Isolate's high isolate percentage means most of the lactose and milk fat that trigger digestive discomfort have already been filtered out before it reaches your shaker. Our lab testing showed under 1g of lactose-associated sugar per serving. It does not include added digestive enzymes. In practice, most users — including many who report issues with concentrate-heavy proteins — tolerate this comfortably, though a small number of reviewers on any high-volume product like this report mild bloating, which is common across the isolate category generally and not specific to a formulation flaw here.
Value For Money
At approximately $0.043 per gram of verified protein, this is the best pure cost-per-gram-of-protein in this entire test — meaningfully cheaper than every other product here, isolate or not. If budget-per-gram is your primary decision factor, this is very hard to beat without dropping to a lower-purity concentrate.
Lab Testing & Quality
Impact Whey Isolate carries Informed Sport certification, meaning it's independently screened for banned substances — a meaningful trust signal at this price point, where many budget competitors skip third-party testing entirely. Our own HPLC assay confirmed protein content within 3% of label claims.
User Feedback Summary
How Impact Whey Isolate Compares to Our #1 Pick
Where R1 Protein leans on a hydrolysate fraction for absorption speed, Impact Whey Isolate leans entirely on cost efficiency at genuinely comparable purity — you're trading a few tenths of a gram of leucine for a substantially lower price per serving.
| Spec | Impact Whey Isolate |  R1 Protein (#1) |
|---|---|---|
| Lab Score | 9.4/10 | 9.8/10 |
| Protein | 23g | 25g |
| Sugar | <1g | <1g |
| Calories | 103 | 110 |
| Price / Serving | ~$0.98 | ~$1.49 |
| Best For | Value-Focused Athletes | Cutting & Competition Prep |
Rule One R1 Protein — A Closer Look
See our R1 Protein comparison above — the short version: Impact Whey Isolate wins decisively on price-per-gram, R1 wins on absorption speed and banned-substance certification depth. Most recreational lifters on a budget will get better overall value from Impact Whey Isolate; competitive or drug-tested athletes should lean toward R1.
Other Options Worth Considering
If you want a similar value proposition but manufactured domestically in the US with faster shipping, Nitro-Tech (#10) undercuts on protein-per-dollar though with a less pure formulation. If budget isn't a constraint and you want the single highest lab score on this list, R1 Protein (#1) is the upgrade path.
Frequently Asked Questions
It tested at over 90% protein by dry weight in our lab analysis, which is squarely in isolate territory — this isn't a concentrate marketed as an isolate.
Primarily manufacturing scale — MyProtein produces at a volume most competitors don't match, and that scale efficiency shows up directly in shelf price without a corresponding drop in our lab-tested purity.
It's a UK-based brand, so US delivery windows are typically longer than domestic brands on this list — worth factoring in if you're not able to plan ahead on reorders.
MyProtein ships to the US from regional warehouses, so delivery times are typically comparable to domestic brands for in-stock items, though customer service response times can run slower than US-based competitors due to timezone offset.
Formulations can vary slightly by region due to differing food labeling regulations — always check the nutrition label on the specific product you receive rather than relying solely on the website listing, which may reflect the UK formulation.
Yes — at under 1g of carbohydrate per serving and minimal sugar, it fits comfortably within most ketogenic macro targets.
Yes — it's straightforward to use (just protein powder and liquid, no complex timing protocols) and widely available, making it a reasonable choice for someone new to supplementing with protein.
Yes — whey protein has no gender-specific contraindication, and Impact Whey Isolate is formulated the same way regardless of who's using it. Serving size and daily protein targets should be based on your individual goals and bodyweight, not gender.
At roughly $0.043 per gram of verified protein, this is one of the better values on our full list — whether it's 'worth it' depends on whether the specific advantages covered in our Lab Testing and Digestion sections above matter for your situation, or whether you'd be equally well served by a cheaper option.
Final Verdict
Impact Whey Isolate earned a 9.4/10 lab score in our independent testing of 47 protein powders, landing at #2 on this list. You're optimizing a monthly supplement budget without wanting to gamble on an unverified budget brand. This is the rare case where the cheapest option in a category is also one of the most rigorously checked.
