What happen to bestie?

Basically one of my best friends had to move to another city for highschool going into grade 9. He was my best bud throughout elemtray school and i just have a question, i dont wanna ask him but when he left after grade 8, he was about 5 foot, he was a bit overweight, his teeth were crooked (like very bad) he had major self esteem issues and basically just didnt like to do much (lazy) even threw all this i was still his best bud and we had a great time. About 2 weeks ago i went to visit him after not seeing him for like 3 years and when i saw him i almost cried cuz it didnt look nothing like him this new person was the same size as me (i'm 5'6) he had freaking amazing straight teeth and bleaching white he was about my weight(150-160) but he had muscle on him and basically when we met up we were gonna go play soccer (and now i know why he is so active its crazy) i didnt want to be rude and ask him wtf happened to you cuz i never judge him in gr 8 but what could have happened to him to make him change so much. He looks good (im not gay, just saying) and hes good at soccer something he never even played in gr8. what do u think made him changed and like whyd he do it lol..