nutrition vs sustenance

nutrition and sustenance both are nouns.

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

As nouns, nutrition and sustenance are synonyms defined as:

Other synonyms of nutrition include aliment, alimentation, nourishment, nutriment, victuals.

nutrition (noun)	sustenance (noun)
the scientific study of food and drink (especially in humans)	the act of sustaining life by food or providing a means of subsistence
a source of materials to nourish the body	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	the financial means whereby one lives