Unfortunately it comes down to money I believe. You did not say how old you are, how long you think you have left, or if you are wealthy already. For me it co

Unfortunately it comes down to money I believe. You did not say how old you are, how long you think you have left, or if you are wealthy already. For me it comes down to a question of what pays the best (or has the realistic potential to pay the most in the near-to-medium term) for my current or near-to-medium term skills. I need money to live my life and do things that are meanginful and important to me and my family. Selfish? perhaps. But I live a very comfortable & happy life with a very easy but well-paid 9-5 job and can now donate large sums of money to charities and people who want to do more useful things in many different fields (i.e. more than a single person could ever devote their attention to) - to quote Homer Simpson: Money can be exchanged for goods and services. Money makes the world go around as they say, so IMO it is worth finding the function that maximises that. If money is equal between what you want vs what you feel you should, go with what you want vs what you feel is the most important. The reason I say that is that what feels most important now (e.g. you mention healthcare) may not still be important in the middle-term, so you might work on something you dont like but feel is worthy, only to have that problem "solved" by someone else at some point in the future, leaving you with a load of wasted time and regrets about being morally-worthy and "sacrificing" your career/life on something you did not actually enjoy or want to do but that you felt someone-really-ought-to-be-doing-this, but then ultimately you and your work is now effectively redundant because someone else did it better/cheaper/faster. E.g. take computer vision. People have been working with LIDAR and things like depth perception algorithms and all sorts of stuff for years and years and years (think OpenCV et al) in an effort to make computers "see", then out of seemingly nowhere deep learning and CNNs come along and now pretty much anyone with a graphics card can train up a network in a weekend that out-performs decades of research into "traditional" computer vision techniques. With healthcare I can only imagine that this is worse - you could spend years working on a treatment for something, only for a cheaper/better one to come out from a competitor and make your work worthless, or some breakthrough to open up a more promising area of research again making your work worthless. tl;dr - YMMV, I think its ok to be selfish in what you chose to work on. Trust your gut. If you want to work on Healthcare go for it, but if you want to work on something else than that is ok too.