Caffeine is a stimulant which can be found in coffee, tea, colas and chocolate.
No one knows the exact amount we should limit ourselves to. As with all ingredients in foods, I advise moderation. I also include a couple of cups of tea per day as the latest research finds that black and green tea contain antioxidant substances that may lower the risk for certain cancers. The recommended maximum daily intake is 450 mg caffeine per day. I recommend a maximum of four cups coffee or tea per day, and a maximum of three cans of diet pop.