Choose XWERKS Grow if New Zealand grass-fed sourcing and a stevia-sweetened chocolate formula are your priorities. Choose Myprotein Impact Whey Isolate if the lower current cost per serving matters more. The chocolate versions compared here both provide 25g of protein; the useful differences are ingredients, sourcing, testing, and price.
By XWERKS. This is a brand-authored comparison using U.S. product information checked November 4, 2026. It is a label-and-price review, not a hands-on taste test or a clinical comparison.
Jump to nutrition, ingredients and sourcing, cost per 25g of protein, or which one to choose.
How does the nutrition compare?
Grow Chocolate and Impact Whey Isolate Chocolate Milkshake have the same labeled protein per serving. Grow's current product-page panel lists 10 fewer calories, 2g less carbohydrate, and 0.5g less fat. Those are small macro differences; they do not establish a difference in training results.
| Label detail | XWERKS Grow Chocolate |
Myprotein Chocolate Milkshake |
|---|---|---|
| Serving size | 1 scoop, about 32g | 1 scoop, 32g |
| Protein | 25g | 25g |
| Calories | 110 | 120 |
| Carbs | 1g | 3g |
| Total fat | 0.5g | 1g |
| Added sugars | 0g | 0g |
| Sweetener | Stevia | Sucralose and acesulfame potassium |
| Milk allergen | Contains milk | Contains milk |
Sources: Grow's chocolate nutrition panel and Myprotein's U.S. Chocolate Milkshake back label. Values describe the powder, before adding milk or other ingredients. Always follow the label on your purchased pack.
Flavor matching matters here. Myprotein's general product-page nutrition table is explicitly based on its unflavored version. We used the chocolate pack's own label for the comparison above. Grow's Peanut Butter flavor also differs from Chocolate, so neither column should be treated as a promise for every flavor.
Both selected products use whey protein isolate. If you are deciding whether isolate is the right category in the first place, start with our whey isolate vs. concentrate comparison. Buying a more expensive powder does not, by itself, demonstrate better results.
Ingredients: the clearest difference is the sweetener
Grow Chocolate is the more direct fit if you want a flavored whey isolate without sucralose or acesulfame potassium. Its current ingredient panel lists whey protein isolate, cocoa powder, natural flavors, xanthan gum, and stevia.
Myprotein's Chocolate Milkshake formula uses a different flavor and texture system. Alongside whey isolate and cocoa, its pack label identifies natural and artificial flavoring, sunflower lecithin, cellulose gum, the two sweeteners listed above, and hydrogenated coconut oil.
The practical question is which formula matches your preferences. A longer ingredient list is not, on its own, proof of inferior protein or an unsafe product. Likewise, a stevia-sweetened formula does not guarantee that everyone will prefer its taste or tolerate it better.
If you want no added sweetener at all, Myprotein also lists an unflavored option. That is a separate formula to evaluate, rather than a reason to assume every Myprotein flavor has the chocolate version's ingredients. Check the exact flavor before ordering.
What does New Zealand grass-fed sourcing add?
Grow makes a specific sourcing commitment: whey isolate from grass-fed cows in New Zealand. That gives shoppers who care about dairy origin a clear reason to consider it.
The standard Impact Whey Isolate listing reviewed here does not make the same New Zealand grass-fed claim. Myprotein separately sells a product called Grass-Fed Impact Whey Isolate; that is outside this comparison. Do not transfer claims between those two products.
Choose Grow for that stated sourcing and your preferred formulation. This comparison does not establish that grass-fed Grow produces more muscle growth than an equal serving of the competing isolate. Our guide to whether grass-fed whey is worth the extra cost explores that buying decision further.
Which costs less per 25g of protein?
At the prices checked, Myprotein's 25-serving Chocolate Milkshake pack costs about $0.35 less per 25g of protein. That is a promotional-price comparison, not a permanent price ranking.
| Price measure | Grow Chocolate |
Myprotein Chocolate Milkshake |
|---|---|---|
| Selected pack | 30 servings | 800g; about 25 servings |
| Displayed purchase price | $69.00 | $48.74 promotional price |
| Total labeled protein | 750g | 625g |
| Cost per serving | $2.30 | $1.95 |
| Cost per 25g protein | $2.30 | $1.95 |
Price sources: Grow Chocolate, one-time purchase and Impact Whey Isolate, 800g Chocolate Milkshake. No subscription, extra coupon, delivery charge, or tax is included. Prices and availability can change.
Use this calculation whenever the pack sizes or offers change:
Cost per 25g of protein = pack price ÷ (servings per pack × protein grams per serving) × 25.
- Grow: $69 ÷ (30 × 25g) × 25 = $2.30.
- Myprotein: $48.74 ÷ (25 × 25g) × 25 = $1.95, rounded.
This is more useful than comparing bag prices alone. The selected Grow bag contains five more labeled servings, and a scoop of powder is not the same thing as a gram of protein.
For a 30-serving equivalent, the checked Myprotein price works out to $58.49, versus $69 for Grow: a difference of about $10.51. That is a proportional calculation for comparing value, not a 30-serving Myprotein pack you can buy at that price.
The offer can change the decision. Myprotein also displayed a crossed-out price of $74.99 for the selected 25-serving pack. At that price, its cost would be about $3.00 per 25g of protein. Recalculate using the actual price available to you, including shipping when comparing final order costs. Do the same if you choose a subscription or a different pack size.
Testing: compare what the evidence actually covers
Independent testing can answer different questions. A contaminant screen, a protein-content verification program, and a banned-substance testing program are not interchangeable.
Myprotein Impact Whey Isolate (USA) appears in the Informed Choice product directory, which provides batch-test records, and the Informed Protein certified-products list. Informed Protein describes its program as independent verification of protein label claims. Those are useful credentials to inspect by exact product and region.
Grow's product page links to an Ellipse Analytics pesticide-screen report. The linked report page is dated November 2023 and reports results for that screen. It should not be presented as equivalent to a current sport-certification listing or as proof that every possible contaminant was tested.
If a competition or team requires a particular certification, make that requirement part of your purchase decision. Check the certifier's current product and batch records; a general testing statement alone does not tell you whether a product meets that requirement.
Which whey isolate should you choose?
Choose Grow Chocolate when the sourcing and formulation are worth the price difference to you. You get a stated New Zealand grass-fed source, a stevia-sweetened chocolate formula, and 25g of labeled protein per serving. That is the concrete case for paying for Grow.
Choose Impact Whey Isolate when the checked offer delivers better value for your priorities. It is a reasonable option for shoppers comfortable with the selected formula who want a lower current cost, or who want to investigate its named certification programs. Compare the exact regional product and flavor rather than a headline starting price.
For either brand, choose a flavor you expect to use consistently. We have not scored taste, mixability, or digestive comfort here because those would require a different kind of comparison. The ingredient and price checks can narrow your choice without pretending to answer those questions for you.
Questions to check before ordering
Is Impact Whey Protein the same as Impact Whey Isolate?
No. They are separate Myprotein products. This article compares Impact Whey Isolate; a price or label for Impact Whey Protein should not be substituted into the table. Confirm the complete product name in your cart.
Are either of these chocolate powders dairy-free?
No. Both labels declare milk. Isolate is still a milk-derived protein, and the label's carbohydrate or sugar total is not a measurement of its exact lactose content. Neither option fits a dairy-free requirement.
Can I use either powder in food instead of a shake?
You can use whey isolate in foods such as yogurt bowls and overnight oats. Weigh the powder according to the recipe and your product label; do not assume different brands' scoops hold the same amount. Our six whey protein recipes offer breakfast, snack, and dessert ideas.
Choose your Grow flavor
If New Zealand grass-fed sourcing and stevia-sweetened chocolate are what you want in your daily protein, review Grow's current label and purchase options.
Sources and comparison method
We reviewed the manufacturers' U.S. product pages, Myprotein's flavor-specific package image, XWERKS' linked report, and the certifiers' directories on November 4, 2026. Nutrition comes from the selected chocolate versions; prices are the displayed one-time purchase offers for the stated packs. Calculations use labeled servings and protein, with final dollar amounts rounded to the nearest cent. We did not independently assay either powder or conduct a taste trial.
- XWERKS Grow: chocolate nutrition, ingredients, sourcing, and purchase options
- Myprotein Impact Whey Isolate: selected U.S. Chocolate Milkshake pack and its back label
- Informed Choice: Impact Whey Isolate (USA)
- Informed Protein: certified-products list and testing scope
- Ellipse Analytics report linked from Grow's product page
