lilmisspotatoes said:
Thank you... seeing that post kind of made me go 'wtf? really?'
I'm not anorexic, in the sense that I'm not staring into the mirror going 'omg I'm so fat, I need to lose weight, I'm not going to eat'. I simply don't find myself getting hungry on a 'normal' basis. And the funny thing is that I'm still technically obese (I'm currently a size 16, but a little less than 8 months ago I was a 24), but I keep losing weight.
According to WebMD, a person my size burns roughly 1800 calories just by existing. By doing what I do (walking anywhere from 1.5 - 3 miles a day on top of working a fairly physical job), it says I need to be taking in about 2800 calories just to MAINTAIN my weight. That's ridiculous, is it not?
Sorry for the shocker Lilmisspotatoes, it wasn't aimed at you. All I was pointing out was that in your post you didn't provide a lot of information and it was possible that, given the information you provided, you could be anorexic, and in that light some of the comments made could be incredibly irresponsible. It wasn't meant to imply that you were anorexic, merely that it was a possibility that a responsible person should consider when replying.
There are many possible reasons why you could be losing weight, and I'll sketch the two big ones and then you can consider why your friends might want you to visit a doctor. I'm not on anyone's side here, just giving an opinion:
1. Metabolic rate and endocrine function
WebMD and other online services can't measure your metabolic rate. I used to eat more than a pound of chocolate a day until I was about 21, plus 4 full-sized meals, and I never put on an ounce of fat. I wasn't particularly active, I used to work out about an hour a day either doing martial arts or at gym, but my calorie count was waaaaaaay over where it should have been, in fact I should have been the size of a house.
When I turned about 25 my metabolism began to slow and now I have to really watch what I eat or I put on weight, and I have to exercise regularly or I start to get a spare-tyre.
The thing is that metabolic rate is primarily regulated by the endocrine system (brain hormones), and the chemicals that control metabolic rate are primarily controlled by the hypothalamus (and also your pituitary gland to a lesser extent). If you've experienced a change in metabolic rate then it means that something may have happened to your hypothalamus, and while that can be a perfectly normal change it could also signal something is wrong. It never hurts to get it checked.
2. Parasites
No-one really wants to think that they might have worms and it's a bit of a conversation-stopper if you say, "Hey, I discovered I've got a MONSTER tape-worm and it's going great things for my dieting!". People will tend to shuffle away and wash their hands

. However about 25% of people in the U.S. (a first-world country) have a parasite of some kind, and most of them are easily dealt with. A tape worm could also possibly account for your weight loss, and initially it would be beneficial, right up until the point where it starts to leech important nutrients from your system and eventually kills you (although this would take a LONG time). Ironically parasites are mostly very easy to get rid of and a couple of de-worming tablets will deal with it.
These are just two possibilities, I'm not going to try and diagnose someone over the internet, but they are both good reasons to go into your doctor, describe what's going on, put it in context that at the moment it's actually having a beneficial health effect, and that it's your friends who are concerned. The doc will probably run some tests and eliminate the dangerous possibilities and give you and your friends some peace of mind.