vitamin vs nutrition

vitamin and nutrition both are nouns.

Word	Noun	Adjective	Verb	Adverb
vitamin	Yes	No	No	No
nutrition	Yes	No	No	No

As nouns, nutrition is a hypernym of vitamin; that is, nutrition is a word with a broader meaning than vitamin:

vitamin: any of a group of organic substances essential in small quantities to normal metabolism
nutrition: a source of materials to nourish the body

Other hypernyms of vitamin include aliment, alimentation, nourishment, nutriment, sustenance, victuals.

vitamin (noun)	nutrition (noun)
any of a group of organic substances essential in small quantities to normal metabolism	the scientific study of food and drink (especially in humans)
	a source of materials to nourish the body
	(physiology) the organic process of nourishing or being nourished; the processes by which an organism assimilates food and uses it for growth and maintenance