Supports Upper Respiratory HealthThe Better Vitamin C®500 mg Non GMOClinically Studied Vitamin CStomach Friendly Dietary Supplement Suitable for VegetarianSodium Free Immune & Upper Respiratory Health Support Ester-C® is the unique immune health formula containing a proprietary, clinically studied Vitamin C that stays in your immune system for 24 hours†. Ester-C® Vitamin C is clinically shown to last longer than regular vitamin C. That's because Ester-C® Vitamin C is carefully formulated to contain vitamin C metabolites, the same metabolites that are naturally produced by your body and help enhance the retention of vitamin C by your white blood cells, a vital part of your immune system. So once you take your daily dose of Ester-C® Vitamin C, it gets into your white blood cells, and stays there - for up to 24 hours. Vitamin C also contributes to the health of your upper respiratory tract, plus, Ester-C® Vitamin C is manufactured without chemicals to neutralize pH, which means it's non-acidic and gentle on your stomach. Ester-C® is the kind of support you can count on 24/7   Ester-C® Vitamin C lasts longer than regular Vitamin C in White Blood Cells over 24 hours *† Enjoy the benefits of Ester-C® Vitamin C every day   24 Hour Immune SupportClinically studied to last longer than regular Vitamin C†Non-acidic and gentle on the stomachSupports upper respiratory healthPotent antioxidant support Not all Vitamin C is created equal ... There is only One Unique Ester-C® formula †Ester-C® Vitamin C has been clinically studied to stay in your white blood cells for up to 24 hours, which is longer than regular Vitamin C. White blood cells are an important part of the immune system.