Bad thyroid value (female)

Hey fellas,

Maybe I should have posted this in the Diet forum or something but the mods are of course free to move it if it doesn´t fit here.
I´ve posted this in several other boards and I´m trying my luck here now. (Hoping for a answer from buffdoc and others)

The problem:

I have this female friend that seem to have some sort of metabolic disturbance. To give a little background info we have to go back a year. Summer of 2002, she´s sick (the flu) and gains 15lb in one week. After a month she steps on the scale and it has +35lb added to her bodyweight. Ever since shes been trying to loose these extra pounds. After beeing on 1500-1700kcal/day (40-40-20) for months she still can´t get rid of the extra weight. So naturally she goes to the hospital to get some bloodworks done. They report a low thyroid value. (don´t remember the exact number) (Her liver values were also quite bad (suggesting foodpoisoning)) The doctor tells her to exercise more. Well, she walks 20 kilometers every day. She´s physically active at work. She works out 3-4 times/week. She attends to bodypump, aerobics classes she says. (The doc is clueless) As a matter of fact, every doctor she goes to is clueless. Some recommend a thyroid medication called Levaxin but several people she has talked to never lost a pound on this Levaxin stuff and by starting taking it you then have to take it for the rest of your life (as I understood it).
So she gets pushed from one hospital to another the whole time.

Now, some people suggested her to raise the kcal intake to about 2K/day (To stimulate thyroid function). So she did and gained 12lb in a heartbeat, well in a week atleast. The good news is that she don´t gain anymore and she´s been on 2000kcal for a couple of weeks. But she still don´t loose weight, which is her primary goal.

She used a program that calculated how many kcal all her daily activities burns. the program suggested 3000-3500kcal/day.

A couple of years ago she lost 60lb in 6 months just by walking before breakfast for 1-1½ hour. Not counting calories or anything.

Female, 176cm, 80kilo (180lb) Turns 25 may 4th.

The questions:

1. Could she have f*cked up her metabolism herself by underfeeding her body for such a long time? (1500-1700Kcal for months and months)

2. (Related to the first question) Can you control ones metabolism through food?

3. If I get hold of some thyroid medication (t3 or some) for her, could this cause even more trouble for her, shutting down her thyroid completely etc etc?

4. Does ANYONE have the slightest idea for some sort of solution for this problem?

She´s a dear dear friend of mine and I hate seeing her down. The sweetest and kindest person there is. Never puts people down or use foul language. Drug-free of course.

Please help a bro out here, I´ll translate everyones answers to Swedish to the best of my knowledge and forward them to her.

Thanks all!
She is obviously suffering from some type of hormone imbalance. Though you didn't state what type of doctor she has consulted with, the only doctor who could be of any help to her would be an endocrinologist.