I believe you can see that stuff on the Pebble app but you can't sync with Apple health. See this previous pebble blog post: https://ericmigi.com/blog/apple-restricts-pebble-from-being-...
I’m not sure if that’s something the Pebble app uses right now, but it’s certainly possible, and a third-party app could make it happen as well.
Some info from Eric: https://ericmigi.com/blog/apple-restricts-pebble-from-being-...