Roselle, contains one of the highest content of Vitamin C - estimated at 280mg every 100gm of dried calyx of roselle. It's not only vitamin C, it also contains other essential vitamins such as Vitamin D, B1 & B2.
Other than the usual vitamins, it contains nearly 486mg of Calcium, substantial amount of Magnesium, Beta-Carotene, OMEGA-3, Essential Amines, and lots of other useful phyto-resources.
It is thought that the antioxidant chemicals, such as flavonoids, polyphenolics and anthocyanins, contained in the flower play a large role in preventing the oxidation of low density lipoproteins (the “bad cholesterol”). This oxidation is what contributes to atherosclerosis, the build up of a waxy plaque on the walls of arteries.