I have never had a problem following the rule of only 2 oz. of half and half outside my RM coffee...and start the day with coffee and the 2 oz. every day.

I would not have more than the 1 cup outside of my rm..though I might have a black coffee...but... I have read about caffeine triggering insulin release in some...which would then def. be an issue. (you can google for articles on this).

I think it is a very individual thing...if you feel the rest of your food is spot on for what it should be, then look at how much coffee you are having and try a test of lessening it.