I chose economics, since I, too, did not care much for the level of writing demanded by humanities. If you are not proficient in math up to calculus, however, then economics might pose some minor difficulties. Otherwise, it's a perfect discipline for those who like to apply scientific analysis to problems of immediate social concern. I feel that econ has given me the background to speak with some authority on healthcare issues; and such preparation has come in handy on the interview trail (What's the biggest problem facing healthcare today? Why? How would you fix it? Well, that's easy -- it's misaligned price signals!).
It is certainly a unique major among pre-meds, and its applicability to healthcare has been, in my experience, an asset to my application. There are so many approaches you can take with economics, from econometric/empirical observations to pure theoretics. Take an intro econ class and see how you like it. At the least, it will equip you to be a more engaged citizen, someone in tune with the Washington policy debates (like SS) that will prove to be among the most important of our time!