A new Korean diet is taking the internet by storm, with bold claims of helping individuals shed fat and retain muscle mass in just four weeks. Known as the Switch On Diet, this method was developed by Dr. Yong-Woo Park, a seasoned obesity expert with over 33 years of clinical experience. The program, which incorporates principles of intermittent fasting, gut health optimization, and high-protein nutrition, is gaining massive attention for its structured and results-oriented approach.
What Is the Switch On Diet?
Dr. Yong-Woo Park designed the Switch On Diet to tackle metabolic abnormalities and guide the body toward a healthier weight in a matter of four weeks. Rather than focusing purely on calorie restriction, the program emphasizes metabolic correction, encouraging the body to burn fat efficiently while preserving muscle mass.
This diet isn't just about what you eat—it also highlights when you eat, how you move, and what lifestyle choices you make throughout the day.
Core Rules of the Diet
The Switch On Diet revolves around a few strict yet manageable rules that participants must follow consistently:
- Hydration: Drink 8 glasses or 2 litres of water daily.
- Sleep: Get at least 6 hours of sleep each night to support recovery and metabolism.
- Supplements: Incorporate nutritional supplements as advised.
- Intermittent Fasting: Practice daily fasting for 10 to 14 hours.
- Exercise: Perform high-intensity workouts four times a week.
- Early Dinners: Finish dinner at least 4 hours before bedtime.
- Restrictions: Limit or avoid caffeine, alcohol, processed foods, sugar, and most carbohydrates.
Week-by-Week Breakdown
The Switch On Diet is divided into four distinct phases, each with specific dietary and lifestyle instructions tailored to optimize fat burning, gut health, and muscle retention.
Week 1 – Detox and Gut Cleanse
The first week focuses on cleansing the digestive system and preparing the body for fat loss.
Days 1-3: Participants drink protein shakes four times a day, take probiotics on an empty stomach, and go for an hour-long walk.
Allowed foods include cabbage, cucumbers, broccoli, tofu, and unsweetened yoghurt—ingredients that are easy on the gut and support detoxification.
Week 2 – Intermittent Fasting Begins
In Week 2, the diet introduces more rigorous intermittent fasting:
One Full Fast Day: A 24-hour fast is required. Afterward, it should be broken with a high-protein dinner.
Daily Diet Plan:
2 protein shakes per day.
Low-carb meals including vegetables and white rice for lunch.
No-carb, high-protein dinners.
During this week, muscle recovery is prioritized, meaning high-intensity workouts are discouraged on fasting days. Common foods include nuts, legumes, and even a limited amount of black coffee.
Week 3 – Accelerating Fat Burn
In the third week, fasting increases in frequency to enhance fat metabolism.
Fasting: Two non-consecutive 24-hour fasts are introduced.
Food Plan:
Two low-carb meals and two protein shakes daily.
Foods like cherry tomatoes, pumpkins, chestnuts, and berries are included.
Carb-dense foods like sweet potatoes and bananas are allowed post-exercise to aid recovery.
Participants are encouraged to stay active and stick to the high-intensity workout routine (on non-fasting days), further accelerating fat loss.
Week 4 – Maximum Fat Burn
This is the most intense week of the program.
Fasting: Participants undertake three 24-hour fasting periods spread across the week.
Meals: Similar to Week 3, but with a stronger emphasis on timing and nutrient density.
The goal here is to push the body into peak fat-burning mode while continuing to protect and maintain lean muscle mass. The combination of low-carb meals, fasting, and strategic workouts is designed to transform body composition rapidly.
What Makes It Different?
The Switch On Diet isn’t just another fad—it integrates principles from nutrition science, fitness, and metabolic health. Dr. Park’s emphasis on gut health, ketosis, and intermittent fasting aligns with emerging research that shows how digestive balance and meal timing can significantly affect weight loss outcomes.
Unlike extreme diets that lead to muscle wasting or rebound weight gain, this plan includes adequate protein to sustain muscle tissue and encourages a gradual lifestyle changes
Maintenance Plan
The four-week plan doesn’t end at the finish line. To maintain the results, participants are advised to:
- Continue with one 24-hour fast per week
- Maintain a 14-hour intermittent fasting window once a week
- Stick to high-protein, low-carb meals with occasional carbohydrate refeeds
- Stay active and hydrated
- This phase is crucial to prevent regaining weight and to solidify the metabolic improvements achieved during the four weeks.
Is It Safe?
While the Switch On Diet is grounded in sound principles like fasting, hydration, and gut health, anyone considering it should consult with a healthcare professional before starting—especially individuals with underlying health conditions or on medications.
The intensity of fasting and workouts might not be suitable for everyone, particularly those new to exercise or with dietary restrictions.
The Switch On Diet offers a compelling promise: fat loss, improved metabolic health, and muscle retention—all in just four weeks. With its strategic use of fasting, high-protein nutrition, and strict lifestyle rules, it’s no surprise that the diet is catching fire across social media platforms.
Whether it's a game-changer or just another viral trend, one thing’s certain—it’s making
people rethink how they approach fat loss and body transformation.