I'm nearly 36 and in my training experience I've met a number of people significantly older than myself. According to a study in Flight International about 5% of airline pilots come from a background where people change careers late in life. In many cases I would imagine that people need several years steady employment in order to fund the training.
And finally there is a window of opportunity for more mature pilots in some smaller turbo prop companies as they need pilots who are not looking for a useful stepping stone into larger jets.
cheers
MJR