Where have you read that from? In the UK, the maximum weekly allowance is 21 units (14 for women). In fact it's recommended that men drink 1 or 2 drinks a day (I.e. around 14 units in a week, preferably with meals) as this helps lower risk of cardiovascular disease. BUT not all at once! Anything more than 8 units (less than 4 pints) in one day is considered binge drinking. Binge drinking is baaad, mmmkay? The thing is, you're 17 and you don't give a f**k. Drinking 8 pints in one night IS bad for you, and it's a risk you should be aware of. But it's up to you to take that risk if you want to. If you drink in that same pattern, you'll be in a mess by age 40 easily, but most people don't, they get a proper job or whatever and tone it down.