Optimum Nutrition
Micronized Creatine Powder
8.8Excellent
One of America's best-selling creatine tubs: 5 g of micronized monohydrate per scoop, Informed Choice certified, about $0.20–$0.30 a serving.
Informed Choice
4 videos ShopCreatine
Brand profile
Optimum Nutrition
Optimum Nutrition is a sports nutrition brand founded in 1986 by brothers Tony and Mike Costello and acquired by Glanbia PLC in 2008. It is best known for Gold Standard 100% Whey, one of the most widely sold protein powders in the world, and its range also covers casein, plant protein, creatine, amino acids and mass gainers. The company says its products are sold in more than 100 countries, including through Amazon, TikTok Shop and specialty retailers in the US.
- Downers Grove, Illinois, USA
- Founded 1986
- optimumnutrition.com
8.2
Average score
Across 4 products
Testing & quality
Gold Standard 100% Whey, Gold Standard 100% Isolate, Essential AMIN.O. Energy, Creatine and Glutamine are Informed Choice certified (per the brand); other products are not all certified, so check each label.
Optimum Nutrition products we’ve reviewed
Optimum Nutrition
Gold Standard 100% Whey
8.7Excellent
The benchmark whey blend: 24 g of protein per 120-calorie scoop, Informed Choice certified, and a flavor lineup few rivals can match.
Informed Choice
5 videos ShopProtein Powder
Best Value
Optimum Nutrition
Gold Standard 100% Casein
8.1Good
A slow-digesting micellar casein with 24 g of protein per scoop for bedtime or long gaps between meals; thick, filling and fairly priced.
3 videos ShopProtein Powder
Best Value
Optimum Nutrition
Essential AMIN.O. Energy
7.0Mixed
A hugely popular caffeinated amino drink: 100 mg natural caffeine plus a 5 g proprietary amino blend led by taurine, glutamine and arginine, so EAA doses are unknown.
Informed Choice
3 videos ShopAmino Acids (BCAA & EAA)
Video reviews