The closest idiom to this would be "in the pink", which means to be in excellent health and spirits. It's a common phrase used to describe someone who is feeling very well.
Here are some examples of how "in the pink" is used:
* "After a good night's sleep, I woke up feeling in the pink."
* "She's been in the pink ever since she started exercising regularly."
It's possible that "pink health" is a misheard or misremembered version of "in the pink". If you heard someone use "pink health", it's best to clarify what they meant.