HealthFit is a coherent local health-management skill, but it handles very sensitive health and sexual-health data with broad activation rules and privacy/storage guarantees that are stronger than the artifacts enforce.
Install only if you are comfortable storing sensitive health data locally in plaintext and giving the skill file access for tracking, backup, and export. Treat the sexual-health module as optional, avoid entering intimate or medical details unless you explicitly want them persisted, review backups before syncing or sharing them, and do not rely on this skill for diagnosis or treatment.