What is your BS in? Do you have many upper-level bio/chem/phys/math classes under your belt?
As far as an MS in Bioinformatics, no it won't help you if you're doing it just for a "boost." Read Goro's Guide for Reinvention, where it'll explain a lot of ways to improve yourself.
If you're into it and see yourself using it as a physician, why not? It's unique and seems pretty useful down the road if you become a PI in clinical or basic science research. Medical schools aren't going anywhere. This will be my 4th year out of college and I've been loving it.