On the December 1 airing of SBS Power FM's 'Choi Hwa Jung's Power Time', John Park revealed he recently lost about 10kg (~22lbs) and plans to lose another 10kg. 

He explained the reason he went on a diet and said, "I recently went on a show where I traveled to an island with Kang Ho Dong. While monitoring the show, I was so shocked because my head was bigger than Ho Dong hyung."

He continued, "I've been getting very comfortable on broadcasts so I didn't know I've become like this. I felt guilty so I started going on a diet. I've even quit eating my favorite Pyongyang naeongmyeon (North Korean style cold noodles)."