Carbohydrate Metabolism Disorder

High Metabolism or Eating Disorder?
I’m Asian, Male, 18, 50kg and only 165cm tall.
I’ve been eating meals (4 per day) that are relatively large when compared to what others around me eat. They are also heavy in carbohydrates, such as bread, rice, noodles and pasta. I can even offer to help finish half of other people’s food even after finishing my own meal. However, I don’t see any output. I am not growing heavier nor taller, and I hardly visit the toilet to defecate. This has been going on everyday for about 3 years.
My friends say that high metabolism is the cause for this ‘unnatural’ eating habit. But is this the only cause for eating so much? I’ve recently picked up floorball and soccer and play them almost every weekend. Does my lifestyle affect my eating habits? Are there any ways to cut down on consumption (besides medication)?
Anyways, what is metabolism (other than the need for food)? Are there any side effects of having too high or too low metabolism, such as in old age?
High metabolism. The only side effect is that it’s harder for you to gain weight. If you had an eating disorder, you’d be starving yourself and thinking you’re fat even when you’re underweight
Dr Larson hypoglycemia, her own experience

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