I seem to have a very fast metabolism, ever since I was a teenager.
For instance I easily consume 500 calories from non-diet sugar based soda a day and then may typically consumer anywhere from 1500 to 2500 calories based on the food I eat, a lot of which is junk food or per-prepared.
I tend to get very little exercise aside from walking where I need to go. This has been the case for years.
I'm not overweight at all, if anything I am slightly underweight as I am just over 6 feet tall and 175 pounds.
I seem to have a decent stamina being able to keep up with most people in say a random running race or similar spontaneous physical activity. I don't feel tired or anything similar.
If my body is burning off all these calories with no exercise, is this a good thing? What other health effects should I worry about?