Vitamin C supports your immune system as well as whole-body health. Fast C and Bio-Quercetin Phytosome is a unique vitamin C supplement augmented with Bioperine black pepper extract, an ultra-absorbable form of quercetin, and a unique calcium-magnesium mineral complex. Fast C maximizes the absorption and health benefits of vitamin C supplementation.Vitamin C is a potent antioxidant with profound whole-body health benefits. This essential nutrient supports immune health, heart health, iron uptake, collagen formation, and more. Plus indicates that people with higher vitamin C levels are more likely to live longer, healthier lives.