My boyfriends friend is doing a PhD (just coming up to the end of his first year). Apparantly he works 80 hours a week!!! Surely that can't be right, can it? I'm now feeling very worried as I work nowhere near that many hours!!! I don't understand how he has time for a life.

That sounds too much to me. I've been doing avarage of 60 hours of work every week only for the last 2 months but it is for a one-off project that I am undertaking as part of my PhD. I have to put the hours in as too many things need to be done at the same time for it. As soon as that finishes (6 more weeks left), I will go back to my usual 30 hours (max) per week.

80hrs/week in the first year sounds pretty excessive to me!

well, it is unbelievable because in order to work 80hrs a week (i.e. around 14 hrs a day) you need a very strong mental and physical health. To have strong health you need regular meals, sports etc, i.e. time to do it. I dont believe but if it is true, it wont last long. He might end up in hospital, in the best case in a normal one, in the worst- in mental health care institution.
My supervisor says that 5 hours of a good work a day, 6 days a week is completely enought to finish your PhD in decent time.