Advice for teen

Despite my recent weight gain, my nearly 15 year old is very athletic. He takes part in sports for between 1 and 5 hours every day and I'm trying to make sure he has enough protein and fats as he is already lean enough. I'm considering allowing him to have a protein shake on more active days. What do you think?

He is a pescatarian - so doesn't eat meat but does eat fish. His protein comes from Quorn products, cheese and beans; and fats from cheese, occasional avocado (not a plentiful supply in the UK) and nuts; he doesn't like butter/margarine or added oils, so the shake may help to top up his energy?