healthful vs preventive

healthful is not a noun while preventive is a noun.

Word	Noun	Adjective	Verb	Adverb
healthful	No	Yes	No	No
preventive	Yes	Yes	No	No

healthful (noun)	preventive (noun)
	remedy that prevents or slows the course of an illness or disease
	an agent or device intended to prevent conception
	any obstruction that impedes or is burdensome

healthful (adjective)	preventive (adjective)
conducive to good health of body or mind	tending to prevent or hinder
free from filth and pathogens	preventing or contributing to the prevention of disease