I was struggling with how to approach this question as well! I said it in a way as to how I got to where I am now, along with adding in underlying characteristics I have. When I talked about working in healthcare as a CNA and how it has influenced my decision, I spoke in a way the interviewers could see how passionate I was. I interviewed 2 weeks ago and was accepted to the program! When they asked me this, here is how I (briefly) answered:
"I grew up in ___ city in Minnesota, and went to college in Florida to play Division II lacrosse. I started as a crim justice major, but I ended up feeling so bored and that I was not being challenged in school. I switched to biology and fell in love with science, and this is how I was introduced into working in healthcare. I currently work as a CNA in a pediatrics unit and a NICU and I love being able to interact with patients from all ages"
Keep it simple, keep it brief. My interview style was two 20 minute interviews, and from this answer my interviewers were able to ask me multiple questions to continue to get to know me. I do not believe this is the time to brag, I feel you had the chance to do that in your application. Show who you are as a person and be able to make jokes. My mom is a NICU nurse and I work with her from time to time. I was able to joke with the interviewers about how when I was younger, after visiting my mom at work I told her I never wanted to work in healthcare, but during college she helped shape my decision to pursue biology and be a PA! We joked that mothers are always right
This was from my personal experience and I hope having a real example helps you out a bit! Good luck!!