A single cup of coffee contains:
Riboflavin (vitamin B2): 11% of the Reference Daily Intake (RDI).
Pantothenic acid (vitamin B5): 6% of the RDI.
Manganese and potassium: 3% of the RDI.
Magnesium and niacin (vitamin B3): 2% of the RDI.
Though this may not seem like a big deal, most people enjoy several cups per day — allowing these amounts to quickly add up.