I am heavy coffee drinker (5 cups/day) but now am planning to start a family. What is the optimum amount of healthy caffeine intake for me? Pls suggest.

I would not recommend more than a cup per day. That’s enough caffeine you need if you are preparing to get pregnant. It would be best to drink decaf and slowly stop taking it when you are pregnant. It would seem difficult at first, but you will slowly get used to not drinking it.