I understand why it sounds better to drop off the "the" but why is it wrong when we don't ignore the "O" in the beginning of the sentence and translate (albeit awkwardly) as
"The milk has many benefits"
I Think it should be right to translate o with" the" here because it could a specific milk.
Still trying to figure out when, if the definite article isn't there in English, it should be there in Portuguese
There's no secret formula. Unfortunately you just gotta memorize when to use the article or not. When in doubt, I would use the article. Portuguese tends to use an article more often in situations where English omits it.