I'd recommend anyone taking a gap year to consider epidemiology, it has given me a certain set of skills, a toolkit if you will, for appraising evidence, decision making, considering counterfactuals etc. It just changes the way you approach problems, a way that I think is very compatible with the problem solving component of medicine. Besides it has offered me amazing opportunities to work with clinicians and patients. Very happy with my decision, hopefully I can find a way to package the perspective in some of my secondaries for schools with strong or growing schools of public health.
If anyone has any questions, feel free to ask.