Yes, NUTRIENTS is a Scrabble word!

Letter values in Scrabble US: N 1, U 1, T 1, R 1, I 1, E 1, N 1, T 1, S 1.

Is it a valid word?

NUTRIENTS is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

any substance that can be metabolized by an animal to give energy and build tissue
any substance (such as a chemical element or inorganic compound) that can be taken in by a green plant and used in organic synthesis