The 66-year-old who is serving a 33-year prison sentence for armed robbery in Nevada, was reportedly caught stealing cookies from the prison cafeteria.
Simpson, who is a diabetic and has been struggling with his weight while incarcerated, was allegedly stopped by prison guards who noticed the former football great acting suspicious.
When they quizzed him, he revealed a stash of more than a dozen oatmeal cookies, which were then seized.
The guard could have written up Simpson for the attempted cookie smuggle but he reportedly decided to let him off with a warning.
The source said that while Simpson was embarrassed, eating his favorite foods is the only enjoyment he has left.
Besides football, Simpson is most remembered for being acquitted of the murder of his ex-wife and her friend. Though denying his involvement, he wrote the book ‘If I Did It..’