On the June 22nd episode of SBS’s My Little Old Boy, actor Yoon Si Yoon stunned viewers by revealing his intense no-water diet ahead of filming Taxi Driver 3.
Standing at 177cm and weighing in at 67.4kg with a body fat percentage of just 6.7%, Yoon unveiled his incredibly lean physique. Basketball legend and host Seo Jang Hoon commented, “At that percentage, that’s basically no fat left on his body.”
In a previous episode, Yoon had shared, “For ‘Taxi Driver 3,’ I want to show a different kind of presence. I’m trying to give off a completely worn-down, gaunt look.”
And he meant it. “Today’s my no-water day,” he explained. Forgoing even a sip of water for 24 hours, he followed a completely dry meal plan—making dumplings out of dried tofu and pairing them with asparagus. Mid-meal, he grimaced, “Ugh, it’s so dry. So rough,” but quickly coached himself with, “Don’t be weak. Everyone puts in this much effort. Mmm, delicious. So good.” His self-hypnosis drew both laughs and sympathy from the studio.
With just three days left until filming, Yoon pushed himself harder than usual, sweating it out through intense workouts before heading into a brutal 45°C sauna to fully dehydrate. He soaked in a steaming tub for 20 minutes like a UFC fighter to wring out every last drop of water weight—leaving viewers in awe.
By the end of the day, Yoon had dropped to 62.3kg and brought his body fat down to a staggering 3.6%, losing 5kg (approx. 11 lbs) in just 24 hours. The studio hosts were floored. “That’s seriously insane,” they gasped. “He’s incredible.”
Visiting a photo studio to test how he appeared on camera, Yoon said, “I want to make sure I come across exactly how I imagined—sharp, with piercing eyes. I want to show a side of me I’ve never shown before.”
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Upon seeing the dramatic transformation, host Shin Dong Yeob was left in awe, hailing the actor as “a total pro through and through.”
