priestley , 21 , from norwich , norfolk , was once dubbed ` jabba the hutt ' by bullies and became so depressed over his size that he refused to leave his house for a year .
he was just 18 when he took an overdose of 30 pills , but survived , ironically , because he had n't taken enough to defeat his massive frame .
after a year , he would only exercise in the dark from fear others would mock his efforts as he struggled to start shedding the pounds .