Protein Products

Naturally Flavored
100% Casein








Faster digesting protein is desirable immediately before and after exercise to help fuel recovering muscles, but slow digestion and absorption may be more beneficial at other times - including bedtime when your body typically goes for hours without food. Casein proteins are acid sensitive and tend to thicken in the stomach. Compared to some other proteins, it can take longer for our Gold Standard 100% Casein to be broken down into its amino acid subcomponents. Gold Standard 100% Casein is also free of artificial flavors, sweeteners, and synthetic colors and uses only protein from premium micellar casein to create a protein formula that’s truly time-released.

  • No Artificial Flavors, Sweeteners, or Synthetic Colors
  • Loaded with Micellar Casein.
  • 24 Grams of Time-Released Protein per Serving
  • 4.7 Grams of Naturally Occurring BCAAs (Leucine, Isoleucine, and Valine)
  • 4.7 Grams of Naturally Occurring Glutamine and Glutamic Acid in Every Scoop
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Optimum Nutrition Quality

At ON we are proud to know that we are one of the few sports nutrition companies who own and operate their own production facilities. While it's true that ON is one of the world's largest producers of sports nutrition products, we remain focused on being recognized as the best. In fact, our requirements for raw materials are so strenuous that it's not unusual for ON Quality Assurance Technicians to reject entire truckloads of raw materials that do not meet our high standards. We like to think that we take as much pride & care in crafting our award-winning supplements as our consumers do with crafting their physiques and fitness accomplishments.

There is Only One Gold Standard

Optimum Nutrition's Award Winning supplements have consistently delivered the Highest Quality products to athletes across the globe -- Here is a brief look at how.