While the average age of a matriculating OHSU student is a bit higher than average (I think our mean is 26-27 years, the horror), keep in mind that about half of every matriculating class is made up of (unmarried) 22-23 year old students. And, to be honest, the incoming classes seem to get more tall, blond, and attractive with each passing year.
At OHSU, in state students have an advantage when it comes to snagging interview invites, but after that point the decision is based very heavily on your essays, EC experiences, and interviews. Yes, life and healthcare experience will help you stand out at your interviews, but you can certainly stand out even if you are a young applicant from Cali.