I can't gain weight.. What is wrong with me?

Maybe it is something that you are eating that is causing sickness and vomiting.  Try keeping a food diary to see if you have a food intolerance and see your doctor to find the cause if you are no better within a week.

Your only 16. At this age you dont need to gain weight. And your saying already that when your over 100, you get inflammatory disorders or something else. This will be more a reason to keep your weight low.

When you have kids in the 20s or 30s, you will start saying the opposite; but hopefully not if you stay fit and low weight as your now. 

165cm and 92lbs for a teenaged girl does not sound super much when you look up size/age/weight charts,

yet I know a 17yr boy (a boy! you can imagine how skinny he looks)

who is exactly like you re size and weight. BUT he never tries to push his weight, he just is 'thin' and quite happy, sporty, active, without pain, not vomiting though either. That's the difference.

He had as a small child some panels like thyroid and glucose done to see, that no obvious metabolic issues were present as he looked really anorexic from toddler age on.

(did you have that done?)

The difference to you is though, that he on the one hand can eat a lot at once (I have seen it, I would be sick!) without getting sick, but never gains weight.

So I don't know if he would feel sick, if he did actually put on weight.

Since you probably had a growth spurt, I would mention a tiny but mild version possibility to doc if it was by slightest chance possible (since he knows clinical symptoms and you best), and it can be very easily excluded via pain free imaging (x-ray in a barium meal, CT, MRI, ultrasound) since exclusions are also peace of mind.

(I have a teenaged daughter with a lot of health issues going on and this condition was one to exclude since she vomited heaps. Mind you it was not the explanation for her, but exclusion was good too; or even not, since nothing found to physically tackle and hope to be helped...this condition I will mention can be tackled. Don't look up severe cases and don't take every symptom mentioned to heart as it is a range and not everything applying to everyone at all. First of all you don't know if you have it.)

Don't worry please when I mention, yet again, there are mild cases and you sound absolutely not severe at all.

 A growth spurt though can change physical positions:

Search please SMA, Superior mesenteric artery syndrome please.

SMA can mimic an eating disorder and it is important to have it excluded to not be brushed off as that, if you worry and suffer.

Teenagers tend to be brushed off far too quickly for my liking, I have been there with my daughter and found this awfully unhelpful. Rather had something suggested and looked at and not confirmed. Being taken seriously. School absenteeism and so on was thrown at us, psychological disorders and the lot. I am sick of having everything put into this draw as there are physical conditions out there too and just the age of teenager not meaning one is immune to any of those. 

BTW: If you felt sick with every meal, I would suggest a gastric emptying study to see if the stomach emptying was delayed (gastroparesis). Again easy test, doesn't hurt. (my daughter has this confirmed and is only a symptom, not telling as to why)

wiki pedia: 'Since females between the ages of 10 and 30 are most frequently afflicted, it is not uncommon for physicians to initially and incorrectly assume that emaciation is a choice of the patient instead of a consequence of SMA syndrome.'

Please don't worry, you look perfectly fine from this distance, yet it does bother you and the weight does not seem high AND you vomit if you have a normal weight (100lb at 165cm is absolutely normal) and I do take you seriously.

A mild form of SMA jumping to mind or gastroparesis.

All the best,

all should be fine! Enjoy life as you seem otherwise not to feel sick.

 

I would suggest having your thyroid tested. I gained weight and was tested and have an Underactive Thyroid and I gained weight without any diet change. Recently it was the opposite and I lost weight without diet change. I had/have your symptoms. Please let me know if you need to talk further I had to do a lot of research myself.