Year-Round Daily Use; This Ester-C formula with citrus bioflavonoids is suitable for year-round use, but dosage can be increased during cold and flu season, or times of stress.

Immune Support & More; This antioxidant-rich Ester-C formula supports immune health and allergy relief, and helps maintain strong bones, gums, and teeth.

Well Retained; Clinical studies show that Ester-C increases vitamin C levels in the body for up to 24 hours.

Superior Absorption; Regular vitamin C is first buffered with calcium, then a special process transforms it into trademarked Ester-C. This vegan, non-GMO formula contains no dairy, gluten, or soy .

Gentle On The Stomach; Sisu Ester-C 600 mg is a less-acidic vitamin C that is gentle on the digestive system.