Sisu Ester-C - 1000 mg - Clinical tests have shown that Ester-C enters the blood stream and tissues 2 to 6 times faster, and is retained in the tissues 4 times longer than regular Vitamin C. Sisu Ester-C, combined with citrus bioflavonoids a powerful, easy to assimilate antioxidant. Tests have shown that bioflavonoid supplementation, in conjunction with Vitamin C may reduce allergic responses and enhance the natural secretion of insulin, benefiting those with diabetes.