I started to learn in a helicopter aged 61. Trained mainly in a R22. I started in April and had PPL(H) at end of October 2006. It probably took me longer to master basic skills and co-ordination than younger students but I certainly did not find age a hindrance otherwise. I wish I had done it when younger. Having a science background helps with some of the exams. I also did the Robinson Safety course and the instructor mentioned that pilots who have previously flown fixed wings are at disadvantage in an emergency because they tend to revert to initial training and make the wrong move eg push cyclic forward resulting in low g disaster. So I would not advise doing fixed wing training first as really nothing to gain. I had never flown anything before I started. The other important thing mentioned already is passing the medical. But this should not be a problem if the person is reasonably fit. I think it is important to keep fit if you are going to fly because that helps to keep mind alert as well. Although this is important at all ages I would recommend it specially for people my age.