The is not used for general statements, but it is used in specified situations:

Plural Countables
I like sandwiches.
I liked the sandwiches we had in the pub.
Doctors are paid more than nurses.
The doctors in A&E work very hard.
Medicines are usually expensive.
These are the medicines I bought yesterday.

Uncountables
I like music.
I didn’t like themusic in that film.
Advice is sometimes difficult to give.
The advice you gave me was really helpful.
Chocolate is made with cocoa butter.
The chocolate I ate yesterday was  delicious.