What age should you start to drink beer?

Of course they can. But their bodies wont be able to process the alcohol as well as an adult can. They would only be able to consume pint sized sips before becoming completely drunk. There is of course the legality of the matter. As many countries have a 18-21 age limit before being able to legally consume it. They do this, as consuming alcohol while developing can damage brain cells and affect the persons well-being.