What will my unusual probelms cause illness wise?

i am an extreamly fussy eater and do not like alot of foods but ok i eat dryed cerial every morning and a thew hours later i have 2 chocolate bars and a packet of crisps, aat lunch i eat sandwhiches bread and butter and some chocholate bars when i get home for dinner i ear chicken or pasta on their own, and occasionally some fruit, i am part of a sports team and do occasional excerise, the only liquid i drink is water and i drink it alot, what illnesses may i have ?