Probably not, they’re not related. :’) Green (sweet bell) peppers are not yet ripe; red bell peppers are ripe. Green ones are much better after they’ve cooked (not unlike onions, they sweeten up). I’ll eat green peppers in stuff, or as the container for stuffed peppers, but while I like their look, I don’t care for them too much. :’)
Peppers consistently show up on lists of the worlds most nutritious foods.
http://www.brighthub.com/health/diet-nutrition/articles/42835.aspx
Green bells are not unrippened red bells but their own type of pepper.
I have five types, (green, red, yellow, orange and blush) growing in my garden.
Letting some of my chemistry be of some use I have found that they are not so horrendous after cooking [but are still inedible] and that I can eat around them - the stuffing in bell peppers for example - without a problem. So whatever it is is both somewhat heat labile and insoluble.