. "It contains many vitamins, including thiamine (B1), riboflavin (B2), nicotinamide (B3), pyridoxine (B6), folic acid (B9), vitamin B12, vitamin C, vitamin D, and vitamin E. Although B12 is present, whether or not it is bioavailable in meaningful amounts is in dispute, and so many vegetarian dieticians recommend not depending on spirulina powder as a source of B12." . . . . .