I also recently cut down on my caffeine consumption and have felt a lot better.

I used to feel a bit weird sometimes in the afternoon - a nauseous/sickly feeling, and after doing the math on how much caffeine I was having on a regular basis (morning capsule coffee, 3~4 cups of green tea during the work day, and a drip coffee just after lunch), figured it might of been the cause.

Have really cut down to a coffee in the morning, and a cup or two of tea throughout the day, and haven't felt ill since.