I decided to give up caffeine the other day. I haven't been sleeping that well, and my caffeine intake has been steadily increasing over the last few months, so I thought I'd better get it under control. Yesterday was a nightmare! I was feeling really zonked. Today I an feeling pretty good though, so I think I am over the worst. I am interested in measuring two things now - my quality of sleep and my blood pressure. It will be interesting to see if giving up caffeine has any impact.