Yoon Si Yoon is facing controversy for his extreme 5kg weight loss in just one day. The actor revealed his intense no-water diet on the June 22, 2025 episode of SBS’s My Ugly Duckling.
Preparing for Taxi Driver 3, Yoon wanted a dramatically different look. He explained:
“I want to show a new texture to my character — something sharp and hollow, like I’m completely worn down.”
Yoon started at 67.4kg (148.6 lbs) with a 6.7% body fat. To survive the 24-hour no-water day, he ate a strict “zero-moisture” meal of dried tofu and asparagus, known for its diuretic effects.
After one day, Yoon weighed 62.3kg (137.3 lbs) with body fat dropping to 3.6%.
He pushed his body further three days before his shoot, sweating more with intense workouts and a 45°C sauna session for 20 minutes to dehydrate, similar to UFC fighters.
Fans and cast members were stunned by his commitment but raised concerns over his risky methods. Yoon’s transformation demonstrates his extreme lengths to embody a role.
