Singer and actor Jung Chae-yeon, 28, recently stunned fans on social media by showcasing her exceptionally slim "ant waist." On July 2, Jung shared behind-the-scenes photos from promotions celebrating the 10th anniversary of the K-pop group I.O.I. The images from a music show stage highlighted her sharply defined collarbones, delicate shoulders, and a waist so slender it looked as though it could be wrapped within a single handful. I.O.I, originally formed through an audition program in 2016, reunited this May to release their third mini-album, I.O.I : Loop. The group has been met with overwhelming fan support while promoting their title track, "Suddenly."
To achieve her iconic frame, Jung previously revealed that she underwent an intense weight-loss regimen ahead of her debut, shedding 16 kg in just three months to drop from 64 kg to 48 kg. At the time, her daily intake was restricted strictly to soft tofu, soy milk, salad without dressing, and cherry tomatoes. Later, after transitioning into acting, she adapted her routine for filming projects by skipping dinner entirely and sustaining herself on a menu of eggs, bananas, and kongguksu (cold noodles in a savory soy milk broth). While both approaches yielded rapid physical changes, clinical experts note that they carry starkly different nutritional implications.
The Pre-Debut Protocol: Rapid Weight Loss at a Nutritional Cost
Jung’s pre-debut diet is a textbook example of a very-low-calorie diet designed for short-term results. While it successfully delivers immediate weight reduction and provides baseline protein through tofu and soy milk—alongside dietary fiber, vitamin C, and folate from the fresh produce—experts strongly warn against sustaining such a regimen.
An extreme deficit in carbohydrates starves the brain and muscles of critical energy, triggering severe fatigue, diminished concentration, and dropping athletic performance. Furthermore, a near-total absence of dietary fat severely impairs the body's absorption of fat-soluble vitamins (A, D, E, and K), which can disrupt female hormone balances and degrade skin health. Tofu and soy milk alone are also insufficient to preserve lean tissue during rapid weight loss, significantly accelerating muscle wasting, while low levels of iron and calcium elevate the risks of anemia and bone density loss.
The Acting Diet: A More Sustainable, Yet Incomplete Balance
In contrast, the regimen Jung adopted during her acting career shows a marked improvement in nutritional structure. Eggs offer highly bioavailable protein, B vitamins, choline, and lutein, while bananas provide quick-burning carbohydrates, potassium, and vitamin B6 to replenish energy reserves. Meanwhile, kongguksu serves as an excellent vehicle for plant-based proteins, complex carbohydrates, and unsaturated fats, providing a welcome sense of satiety.
However, this menu still suffers from a notable lack of dietary variety. Without dark leafy greens like broccoli or spinach, the body misses out on vital vitamins A, C, and K, as well as essential fiber. Relying solely on bananas limits the spectrum of protective antioxidant compounds, and the exclusion of fatty fish like salmon or mackerel leaves the body deficient in critical omega-3 fatty acids, calcium, and vitamin D.
Building a Healthier, More Sustainable Approach
Ultimately, Jung’s dietary habits align with typical celebrity weight-management protocols engineered to achieve a highly specific aesthetic within a compressed timeframe. While effective for immediate fat reduction, prolonged adherence to such restrictive, low-calorie intake can permanently suppress the basal metabolic rate, cause severe nutrient deficiencies, and cause menstrual irregularities in women.
For the general public seeking lasting wellness, the safest path involves gradual weight reduction anchored by robust protein intake, plentiful vegetables, clean carbohydrates, and healthy fats. Rather than replicating extreme celebrity routines, individuals should focus on filling nutritional gaps. Protein can be sustained through lean chicken breast, wild-caught fish, or Greek yogurt, while complex carbohydrates are best sourced from brown rice, sweet potatoes, or oatmeal. Incorporating a diverse array of colorful vegetables and nutrient-dense nuts like almonds and walnuts ensures an abundant supply of vitamins and essential fats, creating a genuinely sustainable lifestyle.
