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Best Protein Powder

Optimum Nutrition protein powders

7 powders checked · 2 third-party tested · owned by Glanbia · USA

Optimum Nutrition

Gold Standard 100% Whey

Whey Blend · 31 g scoop
Informed Choice
Protein
24g
Sugar
1g
Our score
78/100
$0.36 / servingChecked 2026-10-13
Optimum Nutrition

Gold Standard 100% Plant

Plant Blend · 40 g scoop
Informed Choice
Protein
24g
Sugar
0g
Our score
74/100
$1.42 / servingChecked 2026-10-13
Optimum Nutrition

Gold Standard 100% Isolate

Whey Isolate · 31 g scoop
No third-party testing found
Protein
25g
Sugar
0g
Our score
71/100
$2.35 / servingChecked 2026-10-13
Optimum Nutrition

Gold Standard 100% Casein

Casein · 34 g scoop
No third-party testing found
Protein
24g
Sugar
1g
Our score
63/100
$1.08 / servingChecked 2026-10-13
Optimum Nutrition

Platinum Hydrowhey

Hydrolyzed Whey · 41 g scoop
No third-party testing foundAdded amino acids
Protein
30g
Sugar
1g
Our score
53/100
$3.72 / servingChecked 2026-10-13
Optimum Nutrition

Gold Standard Pro Gainer

Mass Gainer · 165 g scoop
No third-party testing found7 g sugar
Protein
60g
Sugar
7g
Our score
39/100
$7.86 / servingChecked 2026-10-13
Optimum Nutrition

Serious Mass

Mass Gainer · 340 g scoop
No third-party testing found29 g sugar
Protein
50g
Sugar
29g
Our score
39/100
$9.31 / servingChecked 2026-10-13