Health is not an adjective and therefore does not have comparative and superlative forms.Healthy, however, is an adjective, with the comparative form of healthier and the superlative form of healthiest.
healthier
The comparative form of "well" is "better" and the superlative form is "best."
Healthier is comparative of healthy.
healthier, more healthy
healthier
healthier
The comparative form of busy is busier.
The comparative form of dreamy is dreamier
The comparative form of friendly is friendlier.
comparative form is cleaner superlative form is cleanest
The comparative form of "central" is "more central."