IPA: /ˈhɛlθiər/
KK: /ˈhɛlθiər/
More beneficial to health than something else.
Eating fruits and vegetables is a healthier choice than junk food.
Comparative: healthier
Superlative: healthiest
Healthier → It is formed from "health" (from Old English *hælu*, meaning wholeness or well-being) and "-ier" (a comparative suffix indicating more). The word "healthier" means having more health or being in a better state of well-being than before.
Think of 'health' as wholeness or well-being, and remember that 'healthier' means being in a better state of health.