Lord, I know I should get back to studying and stay out of this quagmire, but I can't seem to help myself.
I'm a 2nd yr med student at a highly competitive med school. During my application cycle, I got 12 interviews, 7 acceptances, and was waitlisted at 4. (As far as the quantitative goes, I had a respectable but unimpressive 32/3.6). I thoroughly charmed most of my interviewers because I have great people skills and an interesting backstory. My BMI hovers around 40.
I've been overweight my whole life, save for a few years when I had such a severe eating disorder I kept getting threatened with hospitalization. My lowest BMI, after 12 months of eating pretty much nothing but vegetables, vomiting 6 or 7 times a day, and compulsively exercising, was 25, which still kept me in the "overweight" range. Meanwhile, I looked so superficially healthy that the well-intentioned "You look so great!" "Have you lost weight?" comments came daily.
I eventually sought treatment, and it took a while for me to adopt habits more, uh, compatible with life and success. I gained literally a hundred pounds in about eight months, which have stuck around. (My poor clueless mother is still dismayed that I'm not as skinny as I once was.) These days, I'm good to my body: I eat modest portions of unimpeachably healthy foods, I walk most everywhere I need to go, I have a regular yoga practice, and I'm happy. Not because I have a fantastic body, but because I like my life, and no matter what I look like, my body is adequate to help me achieve my daily and long-term goals - and so I count myself as lucky.
In a small-group session on diabetes, one of my classmates - of whom I am very fond, and who I know to be insightful and lovely in most every context - read aloud our fictitious patient's profile, which stated that she's 5'3 and 230 pounds. "Geez, that's fat!" he blurted out. We all laughed, another group member sweetly admonished his lack of tact, and I considered sharing that I weigh more than that. I generally think that we don't know what various weight really look like on people - and even if we think we do, it can vary so widely. I don't know whether the stated BMI of the decapitated illustrative "Fat Person" above is accurate, but here's another photo for you to consider:
http://www.flickr.com/photos/77367764@N00/1455482846/in/set-72157602199008819/. Her BMI works out to 44ish. I'd encourage anyone who's interested to look around that photo set (it's called 'The BMI Project').
On the interview trail, I also noticed that I was one of very few fat candidates. I also worried about first impressions, and what quick judgments my interview panels might make based on my appearance. But you know what? At my first interview, at an Ivy, my first interviewer was a med student who was also a woman of size. She was hardcore and awesome, and told me about how much she was enjoying her surgery rotation. I had conversations at other schools that touched on my size in a round-about sort of way, and it didn't overtly come up at others. Did it make a difference? Maybe - but I also suspect that my ability to articulate my history with my body, and how it's shaped my approach to medicine and patient care, may have won a couple of panelists over.
I suspect I'm the fattest member of my current group of delightful classmates, but I don't know that for sure. One of my classmates uses a wheelchair. Another has a seizure disorder. There's more than one person with diabetes. Another uses hearing aids. Plenty of others rightfully keep their medically histories to themselves. We all live in bodies - some have more apparent issues than others, and a few might be utterly flawless specimens, but for the most part, we all come with our quirks and our dispositions for eventual pathology. Do you believe that someone who's fat shouldn't be admitted to med school because they're more likely to die prematurely? What about my classmate with a strong family history of BRCA+ breast cancer, or my ethics professor, whose father died of Huntingtons?
Many of the comments I've read in this thread reveal a mindset that's pretty blatantly discriminatory, even if some also display a measure of good intention. I'm dismayed by the flippancy and revulsion in some of the comments. You cannot be a good clinician if you find a good majority of your future patients disgusting.
Should the OP have had that conversation with his friend? My vote would be Hell to the No - not because he's wrong about possible size-based discrimination, but because he's shown that he has a monumentally shallow conception of what it means to be fat in our society and in this profession we've chosen. That size and health aren't flawless correlates. That we live in a culture where weight is bound to perceived self-worth. That safe, healthy weight loss in the time frame he's suggesting is basically impossible. That his friend's experience in the world, with all his accomplishments and all the subtext our culture reads into his body, is so much richer and more nuanced than the OP seems to have considered.