Isopure Zero Carb 100% Whey Isolate Unflavored vs Levels Grass Fed Whey Unflavored
Isopure Zero Carb 100% Whey Isolate Unflavored (#4) vs Levels Grass Fed Whey Unflavored (#5): in our Whey Protein Powders scoring the Isopure Zero Carb 100% Whey Isolate Unflavored totals 7.2/10 and the Levels Grass Fed Whey Unflavored 6.9/10.
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TopsFive comparison scores
Side by side
| Isopure Zero Carb 100% Whey Isolate Unflavored | Levels Grass Fed Whey Unflavored | |
|---|---|---|
| Price | — | — |
| Protein | 25g per scoop | 25g per scoop |
| Type | Ion exchange + microfiltered whey isolate | Grass-fed whey (unflavored) |
| Servings | 47 | 71 |
| Carbs | 0g | — |
| Additives | Minimal | — |
| Testing | — | Rigorous testing (unspecified) |
| Mixability | — | Sunflower lecithin blend |
How they differ in real use
Built from our whey protein scoring, each product's published specifications, and verified owner feedback — not hands-on testing.
Both the Isopure Zero Carb 100% Whey Isolate Unflavored and the Levels Grass Fed Whey Unflavored made our Top 5 Whey Protein Powders, at #4 and #5. Ultra-clean ion exchange + microfiltered whey isolate with essentially just whey as the ingredient. 4.4 stars from 36,500+ ratings and good value (~23.04 g/$), but no third-party certification on Amazon. Simple grass-fed whey with only whey protein + non-GMO sunflower lecithin. Respectable ~21.92 g/$ value but no named certification—only mentions 'rigorous testing' without specifics.
We score whey protein powders on Protein Quality (35%), Third-Party Testing (25%), Taste & Mixability (20%), Ingredient Quality (10%) and Value (10%). On that basis the Isopure Zero Carb 100% Whey Isolate Unflavored totals 7.2 out of 10 and the Levels Grass Fed Whey Unflavored 6.9. The widest gap is Protein Quality, where the Isopure Zero Carb 100% Whey Isolate Unflavored scores 9 against 8 for the Levels Grass Fed Whey Unflavored — amino profile and purity. Third-Party Testing also separates them: 3 for the Levels Grass Fed Whey Unflavored versus 2 for the Isopure Zero Carb 100% Whey Isolate Unflavored.
On paper, the specifications that actually differ: Type — Ion exchange + microfiltered whey isolate on the Isopure Zero Carb 100% Whey Isolate Unflavored versus Grass-fed whey (unflavored) on the Levels Grass Fed Whey Unflavored; Servings — 47 on the Isopure Zero Carb 100% Whey Isolate Unflavored versus 71 on the Levels Grass Fed Whey Unflavored. They match on Protein.
Check current pricing at the merchant links below. Owners praise the Isopure Zero Carb 100% Whey Isolate Unflavored for ultra-clean ingredient list (just whey isolate) and ion exchange + microfiltered; the most common complaint is no third-party certification on Amazon page. Owners praise the Levels Grass Fed Whey Unflavored for simple & clean label and 100% whey protein only; the most common complaint is no named third-party certification (mentions 'rigorous testing').
Isopure Zero Carb 100% Whey Isolate Unflavored
- Ultra-clean ingredient list (just whey isolate)
- Ion exchange + microfiltered
- 25g protein per serving
- 4.4 stars (36,500+ ratings)
- No third-party certification on Amazon page
- Unflavored only in this SKU
- 47 servings per container
Levels Grass Fed Whey Unflavored
- Simple & clean label
- 100% whey protein only
- Non-GMO sunflower lecithin for mixing
- 25g protein per serving
- No named third-party certification (mentions 'rigorous testing')
- Unflavored only
- Less documented mixing claims
Which should you buy?
The Isopure Zero Carb 100% Whey Isolate Unflavored is the better fit for clean-label isolate seekers and zero-carb diet — it is the higher-scoring pick here, chiefly for Protein Quality and Ingredient Quality. The Levels Grass Fed Whey Unflavored is the better fit for clean-label grass-fed seekers and those wanting simple ingredients, and the stronger choice if Third-Party Testing matters more to you than the overall score. The Isopure Zero Carb 100% Whey Isolate Unflavored is a poor fit for those requiring NSF certification; the Levels Grass Fed Whey Unflavored is a poor fit for those requiring NSF certification.
Choose the Isopure Zero Carb 100% Whey Isolate Unflavored if
- Clean-label isolate seekers
- Zero-carb diet
- Those wanting unflavored versatility
Skip it if
- Those requiring NSF certification
- Flavor preference
Choose the Levels Grass Fed Whey Unflavored if
- Clean-label grass-fed seekers
- Those wanting simple ingredients
- Good value priority
Skip it if
- Those requiring NSF certification
- Flavor seekers
Common questions
Is the Isopure Zero Carb 100% Whey Isolate Unflavored better than the Levels Grass Fed Whey Unflavored?
In our Whey Protein Powders ranking the Isopure Zero Carb 100% Whey Isolate Unflavored scores higher overall, 7.2 to 6.9, with the biggest advantage in Protein Quality. The Levels Grass Fed Whey Unflavored is stronger on Third-Party Testing, so it is the better pick if that matters most to you.
What is the main difference between the Isopure Zero Carb 100% Whey Isolate Unflavored and the Levels Grass Fed Whey Unflavored?
The headline spec difference is Type: Ion exchange + microfiltered whey isolate on the Isopure Zero Carb 100% Whey Isolate Unflavored versus Grass-fed whey (unflavored) on the Levels Grass Fed Whey Unflavored. In use, the gap that matters most is Protein Quality (9 vs 8 in our scoring): amino profile and purity.