My friend is 5'7-5'8 and she is 98 pounds, she tells me she eats alot and says her metabolism is really fast. She is really thin but she doesn't look as if she is sick, you know? Do you think its really her metabolism?
It is very unlikely that it is her metabolism -- and if it is, a doctor would probably put her on medication (because to be that fast, it would likely be an overactive thyroid).
You don't mention her age, but at 13 she'd be 10lbs UNDER what is considered the minimum medically healthy weight; if she were 17, she'd be 20lbs UNDER...
Not if she's an adult. If she were like 12, then it could that she's still growing and will gain weight as she ages. If she's an adult, she's severely underweight and needs to eat a lot more.
I don't know if she restricts her food, exercises excessively, has an overactive metabolism or has a combination of these things, but she should eat a lot more, I would say at least 3000 calories a day until she gains 20lbs.
shes 14 by the way.
if she's 14 she's in the bottom 1st percentile for age and height -- according to the CDC -- that's very underweight. Again, it's vaguely possible she has a thyroid condition, but that's as close to "naturally" that thin as she'll get -- and her doctors would be medicating.
It's dangerous to be that underweight while in growth stages -- your organs, bones, and muscles can't develop properly.
I assume you're righting here because you suspect that there's something else going on then her metabolism. Have your other friends noticed/talked to you about how thin she is? Does she eat when you're around? Obsess over food or exercise? Get dizzy a lot or complain of being cold? There are many other signs of an ED, and she may have one without showing these signs. If you think she needs help, then you should tell someone. Talk to your parents or someone at school. The earlier she gets help, whether she needs thyroid medication or counseling, the better off she will be.