I majored in Linguistics in college, and YES, it was a much less rigorous major than bio or chemistry, but what was important was that I had a blast studying it. I figured that college was my only chance to study something completely off the wall. What I needed to learn to be a doctor I would learn in medical school.
BUT-- you still have to rock your pre-reqs (i didn't). I had almost a 4.0 in my linguistics major, but only a 2.95 in my pre-med reqs. One of the things I addressed in my personal statement was "why not go into linguistics-- why still medicine?" I anticipated that the adcom would question the huge discrepancy in my grades. I was SO good at linguistics, but only mediocre at my science classes. So in my application, I tried to put forth what I felt I gained from studying linguistics, and how those skills will be an asset in medicine. As it turned out, I wasn't asked about that in my interviews, but maybe it's because I already addressed it in my PS.