I had a friend who was 5' 11' and weighed about 145 pounds. Son of a gun could drink weight gainers and eat like a pig. 7000 calories a day, he'd gain two pounds and then his body would adjust and not gain any more. I hated him for that. hahaha
Everything in moderation is my method. Eat more than you do now and work out as hard as you can. It will come in time...
And enjoy it while it lasts, because as you get older that lightning quick metabolism will slow down. ;-)
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