http://www.healthchecksystems.com/heightweightchart.htmYou're in the NORMAL range of whatever build you have. Bulking up will require weights. If you're doing a lot of cardio, you'll lose weight faster.
With UC, flaring can cause your digestive tract to react quicker and empty faster, but it shouldn't change your metabolism.
Eating a lot can up your metabolism, especially if you're exercising a lot.
Good health choices including good proteins, fats and carbs will at least tell your body you're taking in enough to sustain its actions.
You might also have a higher metabolism normally.
Maybe do lighter exercise, take in more calories and not worry too much about it.
As you age, you'll pack on the pounds a bit easier and miss those good old days..lol.
One important note...have you had your thyroid checked? And are you taking any supplements...if so, which ones?
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