Inkblot - The amount of caffeine varies according to the individual make-up of the person. My personal view is that if the caffeine is interfering with sleep &/or daily functioning, then it is probably time to cut back. If you find yourself unexplanably edgy, nervous, or short with family and friends, caffeine may be contributing.

Another rule of thumb I use is if you think you are ingesting too much caffeine, you probably are.

I hope that this is some help. - Cam