healthiness vs vitality

healthiness and vitality both are nouns.

Word	Noun	Adjective	Verb	Adverb
healthiness	Yes	No	No	No
vitality	Yes	No	No	No

As nouns, vitality is a hyponym of healthiness; that is, vitality is a word with a more specific, narrower meaning than healthiness:

healthiness: the state of being vigorous and free from bodily or mental disease
vitality: a healthy capacity for vigorous activity

healthiness (noun)	vitality (noun)
the state of being vigorous and free from bodily or mental disease	the property of being able to survive and grow
	an energetic style
	(biology) a hypothetical force (not physical or chemical) once thought by Henri Bergson to cause the evolution and development of organisms
	a healthy capacity for vigorous activity