I'd be surprised if it actually requested it. At the same time, it could just be an overly broad interpretation of the fact that they obviously gather any health data you post about on the service.

Not sure how I feel about extending the benefit of the doubt to one of, if not the number one, least trustworthy companies on the planet.

Not really the benefit of the doubt given the app is out and no one has posted about it asking for health permission (AFAIK). Or any other permissions you wouldn't expect for social media (again, AFAIK).