U.S. Vitamins Market Size, Share, Competitive Landscape and Trend Analysis Report, by Source (Plants, Animals, Synthetic), by Type (Vitamin A, Vitamin B, Vitamin C, Vitamin D, Vitamin E, Vitamin K), by Applications (Digestive Health, Immunity, Mental Health, Cosmetics, Performance, Digestive Disorders, Menstrual Health, Pregnancy, Sports and Performance, Others): Opportunity Analysis and Industry Forecast, 2021-2031