Drinking wine to the level that does not affect human being/the Grand Ayatollah Sistani’s answer

The Grand Ayatollah Sistani answered a question about drinking wine to the level which does not affect the human being.

Question: Is it allowed when drinking wine is to the level which does not affect human being?

The Grand Ayatollah Sistani: Drinking wine even for one drop is Haram and is one of the great sins.