I would recommend asking him to consider: your work ethic in class, your performance in the classes, his/her opinion of you going into healthcare.
I like the recommendation of meeting with them for a while so they can kind of interview you. That is what I did for my letters. My professors asked for a 10-15 minute meeting where they asked me a few questions about why I wanted to go into healthcare, my interest in podiatry specifically, etc. I think this gives them more to work with when writing their letters. I would at least consider offering them the option to meet with you if they think that would help them write your letters.
Best of luck! 👍