Explanation:
1 cut down or cut back INTRANSITIVE/TRANSITIVE to start doing less of something, especially because it is bad for your health
The doctor advised him to cut down his working hours.
cut down on: I’m trying to cut down on salt.
2 (cut down something) to reduce an amount of something
How can you cut down the risk of cancer?
cut down on: These improvements will cut down on traffic noise.
