April 25 (Reuters) - Unilever's underlying first-quarter sales grew by a better than expected 4.4%, it said in a trading update on Thursday, as one of the world's biggest consumer goods companies won back consumers who had traded down to cheaper products.

The company said it was confident in its ability to deliver sustained volume growth and maintained its full-year outlook.

(Reporting by Agata Rybska Editing by David Goodman)