Singer Lee Suhyun revealed her successful 30kg weight loss journey through her YouTube channel, 'Lee Suhyun Official.' In the video, Lee Suhyun shared her experience of overcoming a long slump and mental difficulties while taking on the challenge of dieting.

Lee Suhyun disclosed that she temporarily stopped her activities and lived as a recluse due to the burden, guilt, and frustration she felt during her brother Lee Chanhyuk's military enlistment and solo album preparation. During this period, she gained 30kg over 1 to 2 years due to binge eating, and explained that her self-esteem lowered, and she was diagnosed with social anxiety disorder, depression, insomnia, lethargy, and panic disorder. After visiting a hospital at Lee Chanhyuk's suggestion, she gained the will to recover and decided to diet after completing the Santiago pilgrimage.

With her mother's help, Lee Suhyun lost 10kg in a year without exercising, and later recovered her health by staying with Lee Chanhyuk while combining detox and personal training. During the stay, she went swimming on an empty stomach every morning at 7 a.m. and combined diet control with exercise. She mentioned the difficult process, saying, "I eat very little and exercise a lot," and followed strict rules such as adding extra PT sets if she failed to meet her swimming goals. After completing the 22-day stay, she introduced a system that balances freedom and responsibility to develop self-control.

Lee Suhyun said, "The weight I need to lose is 25kg. My ultimate goal is to lose 40kg," and shared that by the third week of her diet, she had only eaten delivery food once and had adapted to healthy eating. She also expressed strong determination, saying, "I want to give up, but I won't." Reflecting on her experience of going to a fasting center with her brother and trainer during the diet, she recalled, "It was so terrible that I never want to go through that again."

Lee Suhyun explained, "From now on, I have to maintain it myself, so I have a system where I gain freedom to develop self-control and take responsibility for it," and added, "I'm losing weight more slowly until summer, and since I'm not as sensitive about my appearance as others, I think I'm already very pretty."

Lee Suhyun warned against the spread of the 'Lee Suhyun diet method' online and declared, "From now on, I will definitely live a healthier and happier life than before, and I will manage to do it somehow." She also said, "I think there are many people like me two years ago. I was sure my life wouldn't change and thought I had to live like this until I died. It's not about exercising or losing weight. I learned to take care of myself and control myself." She added, "Let's atone for the time we wasted. I vowed never to throw away my life and youth again, and as I fought every day, my thoughts completely changed, and my life changed."