Those clinging to Windows 10 Mobile through the Insider program get updates fairly regularly. These updates, which are still essentially beta bits, can cause miscellaneous app issues overall, but particularly for the Microsoft Health app for some reason.
Even though Microsoft posted notice a couple months back that the Microsoft Health app and the Microsoft Band would suffer from issues until an official Windows 10 Mobile OS release was available, folks still seem to want to complain when things don’t work.
However, most Microsoft Health app specific issues are resolved by simply uninstalling and reinstalling the app. One recently reported problem where the Microsoft Health app would crash immediately after tapping the app tile is resolved in this way.