caffeine when pregnant

Nikki • Mother of two angels & 1 rainbow baby, Lillian.
It's strange, I rarely drank pop before being pregnant...however, I crave Code Red Mountain Dew SO badly every day now. I have one like every other day. They say caffeine is bad because baby can't metabolize caffeine like we can... How bad is it to drink a pop every other day? :/ I don't drink coffee...