Hey everyone! I wanted to share something super exciting that’s been trending in Korea—the Switch-On Diet. Developed by Dr. Park Yong-woo, a family medicine specialist at Gangbuk Samsung Hospital, this diet isn’t just about losing weight; it’s about transforming your metabolism and improving your overall health.

I personally tried the Switch-On Diet and lost 7 kg in just four weeks! It’s been a game-changer for me, not only in terms of weight loss but also in how I feel day-to-day. Many people in Korea are raving about their experiences, claiming it helps not only shed pounds but also improves conditions like insulin resistance and liver health.

What is the Switch-On Diet?

The Switch-On Diet is a structured 4-week program that focuses on switching your body’s fat metabolism on. It emphasizes a low-carb, high-protein eating plan while incorporating intermittent fasting. The goal is to help you lose body fat while maintaining muscle mass.

Week 1

✅ Getting Ready for the Switch-On Diet

1️⃣ Follow a 14-hour fasting period between your last meal of the day and the next morning’s breakfast.
2️⃣ Get 7-8 hours of quality sleep, ensuring you sleep between 12 AM - 4 AM for optimal recovery.
3️⃣ Eliminate alcohol and fructose completely.
4️⃣ Set up an exercise routine (at least 3 times a week). Sign up for a gym or find an alternative workout.
5️⃣ Prepare a protein shake with 15-20g of pure protein per serving and minimal carbohydrates & sugar.

🗓️ Day 1 - Day 3: Giving Your Digestive System a Break

[Key Rules]

🚨 Never ignore hunger. Eat when needed.

[Action Plan]

🥗 Meals
✅ Replace regular meals with 4 protein shake meals per day (Breakfast, Lunch, Snack, Dinner – every ~3 hours).
✅ Strictly limit carbs to 20-50g per day.
✅ If you feel hungry between shakes, eat from the approved food list.
✅ Finish dinner at least 2 hours before bedtime, and start breakfast 14 hours after your last meal.
✅ Drink at least 8 cups of water daily.

😴 Sleep
✅ Maintain 7-8 hours of sleep, including 12 AM - 4 AM as mandatory sleep time.
✅ Dim lights in the evening & avoid screens (TV, phone, computer) 1 hour before bed.
✅ A 20-minute nap is allowed during the day.

🏃 Exercise
✅ Move every 30 minutes (light stretching or a 2-3 minute walk).
✅ Aim for at least 60 minutes of walking per day.
✅ Work out at least 4 times a week, incorporating high-intensity exercises if possible.
(If your energy levels are low, start with lower intensity workouts.)

[Approved Foods]

✅ Protein shakes
✅ Probiotics / Synbiotics
✅ Vegetables: Onion, garlic, cabbage, radish, carrot, cucumber, broccoli, bell peppers, avocado
✅ Seasonings: Chili powder, vinegar, pepper, turmeric, herbs
✅ Healthy fats: Coconut oil, olive oil, avocado oil, cold-pressed perilla oil
✅ Drinks: Green tea, herbal tea
✅ Dairy alternatives: Unsweetened plain yogurt, tofu, silken tofu

[Important Notes]

⚠️ If you experience fatigue, headaches, dizziness, or low energy, this is normal carb withdrawal. These symptoms should subside by Day 4 when carbs (in the form of rice) are reintroduced.
⚠️ To support gut health, probiotics/synbiotics can help balance intestinal flora.

🗓️ Day 4 - Day 7: Activating Fat Metabolism

[Key Rules]

🚨 No carbs except rice.
❌ Avoid potatoes, sweet potatoes, corn, fruit, beans, nuts, chestnuts, tomatoes, and high-sugar vegetables (e.g., pumpkin).

[Action Plan]

🥗 Meals
✅ Continue 3 protein shake meals per day.
✅ Introduce 1 regular meal per day (typically lunch) with:

• Rice (⅔ bowl of mixed grains or ½ bowl of white rice)
• Vegetables + High-quality protein sources
  ✅ Limit carb intake to ~80g per day.
  ✅ If hungry between meals, eat from the approved food list.
  ✅ Maintain 14-hour fasting window between dinner and breakfast.
  ✅ Drink at least 8 cups of water daily.

😴 Sleep
✅ Follow the same sleep rules as in Days 1-3.
✅ Maintain 7-8 hours of sleep, including 12 AM - 4 AM.
✅ Avoid screens before bed & dim indoor lighting.
✅ A 20-minute nap is allowed during the day.

🏃 Exercise
✅ Move every 30 minutes (light stretching or a 2-3 min walk).
✅ Walk at least 60 minutes per day.
✅ Add high-intensity interval training (HIIT) for 15-30 minutes, ensuring you’re out of breath.

[Approved Foods]

✅ Everything from Days 1-3, plus:
✅ Rice: ⅔ bowl mixed grains or ½ bowl white rice
✅ Seaweed: Seaweed, kelp, hijiki
✅ Mushrooms: Various types
✅ Condiments: Wasabi, low-sodium soy sauce (in moderation), tofu-based dipping sauces
✅ Fermented foods: Kimchi (consume less than usual)
✅ Animal proteins:

• Eggs
• Fish, sashimi, seafood (oysters, clams, shrimp, crab, lobster, squid, octopus)
• Skinless chicken breast
• Boiled lean pork (suyuk)
• Lean beef (shabu-shabu style)

[Supplement Recommendations]

💊 Consider taking probiotics, multivitamins, omega-3, vitamin D, calcium, magnesium, and high-dose vitamin C for additional support.
💊 If you’re overweight or 40+, Coenzyme Q10 & Alpha-lipoic acid may be beneficial.

🚫 Forbidden Foods (Days 1-7)

🔴 Sugars & High-Fructose Syrups: Soda, sweetened coffee, juice, flavored milk, sugary yogurt, sweets, pastries, chocolate
🔴 Trans Fats: Cakes, microwave popcorn, processed snacks, donuts, deep-fried foods
🔴 Alcohol
🔴 Wheat-Based Foods: Bread, cakes, noodles, ramen, pasta, black bean noodles
🔴 Dairy: Milk, cheese
🔴 High-Saturated Fat Meats: Pork belly, intestines (like large & small tripe)
🔴 Caffeine: Coffee & other caffeinated drinks

Week 2

Gradually increasing carb intake while introducing 24-hour fasting.

[Key Rules]

✅ Pick one day per week for a 24-hour intermittent fast.
✅ On non-fasting days, never skip meals (4 meals per day).

[Action Plan]

🥗 Meals
✅ Choose one day per week for a 24-hour fast:

• Last meal (dinner) → 24-hour fast → Next dinner
• Only water is allowed (NO calories).

✅ On non-fasting days:

• 1 meal per day (usually lunch):
  • Rice (⅔ bowl mixed grains OR ½ bowl white rice)
  • Vegetables + High-quality protein
  • Beans are now allowed (mix them into rice if desired).
• Carb intake: ~80g per day (adjust based on activity level).
• Dinner: NO carbs (including rice).
  • Focus on vegetables + protein and eat until fully satisfied.
• Other two meals: Protein shake.
• 1 handful of nuts per day is allowed.
• Strictly limit all other carbs (potatoes, sweet potatoes, corn, fruit, chestnuts, tomatoes, high-sugar veggies like pumpkin).
• Milk (up to 2 cups/day) and natural cheese (unsalted, unprocessed) are allowed.
• 1 black coffee in the morning is allowed (better if avoided).
• Follow the same 14-hour fasting window between dinner and breakfast.
• Drink at least 8 cups of water daily.

😴 Sleep
✅ Maintain 7-8 hours of sleep (including 12 AM - 4 AM).
✅ Dim lights in the evening and avoid screens 1 hour before bed.
✅ A 20-minute nap is allowed.

🏃 Exercise
✅ Move every 30 minutes (light stretching or short walks).
✅ At least 4 workouts per week, 20-40 minutes of high-intensity interval training (HIIT).
✅ Gradually increase workout intensity daily.
✅ Strength training 3-4 times a week will enhance results.
✅ If you can’t go to the gym, climb at least 15 floors of stairs (3 times daily).

[Approved Foods]

✅ Protein shakes
✅ Probiotics / Synbiotics
✅ Supplements (Multivitamins, Omega-3, Calcium, Magnesium, etc.)
✅ Vegetables: Onion, garlic, cabbage, radish, carrot, cucumber, broccoli, bell peppers, avocado
✅ Healthy fats: Coconut oil, olive oil, avocado oil, cold-pressed perilla oil
✅ Seasonings: Chili powder, vinegar, pepper, turmeric, herbs
✅ Drinks: Green tea, herbal tea
✅ Dairy alternatives: Unsweetened plain yogurt, tofu, silken tofu
✅ Carbs (limited):

• Rice: ⅔ bowl of mixed grains or ½ bowl of white rice
• Beans (black beans, chickpeas, peas, lentils)
• Quinoa
• Seaweed (kelp, seaweed, hijiki)
• Mushrooms
  ✅ Condiments: Wasabi, low-sodium soy sauce (in moderation), tofu-based dipping sauces
  ✅ Fermented foods: Kimchi (consume less than usual)
  ✅ Animal proteins:
• Eggs
• Fish, sashimi, seafood (oysters, clams, shrimp, crab, lobster, squid, octopus)
• Skinless chicken breast
• Boiled lean pork (suyuk)
• Lean beef (shabu-shabu style)
  ✅ Nuts (1 handful per day)
  ✅ Black coffee (1 cup in the morning)

[Tips for Fasting Days]

🟢 Think of fasting as switching to stored energy, not starving.
🟢 Move intentionally—walking and working out accelerate fat burn.
🟢 Supplements are optional on fasting days.
🟢 If hunger becomes too intense, stop at 20 hours and consume a protein shake or meal (try to complete a full fast next time).
🟢 Protein intake is crucial on non-fasting days—eat well before and after fasting to prevent muscle loss.

🚫 Forbidden Foods (Days 8-14)

❌ Sugars & High-Fructose Syrups (soda, sweetened coffee, juice, flavored milk, sugary yogurt, sweets, pastries, chocolate)
❌ Trans Fats (cakes, microwave popcorn, processed snacks, donuts, deep-fried foods)
❌ Alcohol
❌ Wheat-Based Foods (bread, cakes, noodles, ramen, pasta, black bean noodles)
❌ High-Saturated Fat Meats (pork belly, intestines)

🔥 Summary for Week 2:

✅ Introduce one 24-hour fast per week
✅ Increase carbs slightly but keep them controlled
✅ Stay consistent with workouts & HIIT
✅ Eat high-protein meals to maintain muscle
✅ Strictly avoid forbidden foods

Week 3

👉 Boosting results with two 24-hour fasting days per week.

[Key Rules]

✅ Pick two non-consecutive days for a 24-hour intermittent fast.
❌ Do NOT fast for two days in a row.
✅ On non-fasting days, stick to four meals per day—never skip meals.

[Action Plan]

🥗 Meals
✅ Select two days per week for a 24-hour fast (no calories allowed, only water & herbal tea).
✅ Newly allowed carbs:

• Rice, beans, nuts
• Pumpkin, chestnuts, tomatoes, cherry tomatoes
  ✅ Before & after HIIT or strength training:
• One small sweet potato or banana is allowed for energy.
  ✅ Plain yogurt:
• Up to 10 blueberries can be added.
  ✅ One main meal per day (usually lunch):
• Rice (⅔ bowl mixed grains or ½ bowl white rice)
• Vegetables + high-quality protein
• Beans are allowed (mix them into rice if desired).
  ✅ Carb intake: Minimum 80g per day, adjust based on activity level.
  ✅ Dinner:
• NO carbs (including rice)
• Eat plenty of vegetables + protein until fully satisfied.
  ✅ Other two meals: Protein shake.
  ✅ One handful of nuts per day is allowed.
  ✅ Strictly limit other carbs: (potatoes, sweet potatoes, corn, fruit, additional legumes).
  ✅ Milk (up to 2 cups/day) and natural, unsalted cheese are allowed.
  ✅ 1 cup of black coffee in the morning is allowed (better if avoided).
  ✅ Follow the 14-hour fasting window between dinner and breakfast.
  ✅ Drink at least 8 cups of water daily.

😴 Sleep
✅ Maintain 7-8 hours of sleep (including 12 AM - 4 AM).
✅ Dim lights in the evening and avoid screens 1 hour before bed.
✅ A 20-minute nap is allowed.

🏃 Exercise
✅ Move every 30 minutes (light stretching or short walks).
✅ Increase workout intensity:

• 4+ workouts per week
• 20-60 minutes of high-intensity interval training (HIIT)
• Challenge yourself more each session.
  ✅ Strength training 3-4 times per week will improve fat loss and muscle retention.
  ✅ If you can’t go to the gym, do at least 5 stair climbs of 15+ floors per day.
• (Increased from Week 2! 🚀)

[Approved Foods]

✅ Protein shakes
✅ Probiotics / Synbiotics
✅ Supplements (Multivitamins, Omega-3, Calcium, Magnesium, etc.)
✅ Vegetables: Onion, garlic, cabbage, radish, carrot, cucumber, broccoli, bell peppers, avocado
✅ Healthy fats: Coconut oil, olive oil, avocado oil, cold-pressed perilla oil
✅ Seasonings: Chili powder, vinegar, pepper, turmeric, herbs
✅ Drinks: Green tea, herbal tea
✅ Dairy alternatives: Unsweetened plain yogurt, tofu, silken tofu
✅ Carbs (now allowed in moderation):

• Rice: ⅔ bowl of mixed grains or ½ bowl of white rice
• Beans (black beans, chickpeas, peas, lentils)
• Quinoa
• Seaweed (kelp, seaweed, hijiki)
• Mushrooms
  ✅ Condiments: Wasabi, low-sodium soy sauce (in moderation), tofu-based dipping sauces
  ✅ Fermented foods: Kimchi (consume less than usual)
  ✅ Animal proteins:
• Eggs
• Fish, sashimi, seafood (oysters, clams, shrimp, crab, lobster, squid, octopus)
• Skinless chicken breast
• Boiled lean pork (suyuk)
• Lean beef (shabu-shabu style)
  ✅ Nuts (1 handful per day)
  ✅ Black coffee (1 cup in the morning)
  ✅ Plain yogurt with up to 10 blueberries
  ✅ Before & after HIIT or strength training:
• One small sweet potato or banana
  ✅ Newly allowed: Pumpkin, chestnuts, tomatoes, cherry tomatoes

[Pro Tips for Fasting Days]

🟢 Think of fasting as activating stored energy, not deprivation.
🟢 Increase movement—walking & exercise maximize fat burn.
🟢 Supplements are optional on fasting days.
🟢 If hunger becomes too intense, stop at 20 hours and eat a protein shake or meal (but aim to complete the fast next time!).
🟢 Protein is crucial on non-fasting days—eat well before and after fasting to prevent muscle loss.

🚫 Forbidden Foods (Days 15-21)

❌ Sugars & High-Fructose Syrups (soda, sweetened coffee, juice, flavored milk, sugary yogurt, sweets, pastries, chocolate)
❌ Trans Fats (cakes, microwave popcorn, processed snacks, donuts, deep-fried foods)
❌ Alcohol
❌ Wheat-Based Foods (bread, cakes, noodles, ramen, pasta, black bean noodles)
❌ High-Saturated Fat Meats (pork belly, intestines)

🔥 Summary for Week 3:

✅ Introduce two 24-hour fasts per week (not consecutive days).
✅ Increase carb variety slightly but keep portions controlled.
✅ Increase workout duration & frequency.
✅ Consume high-quality protein to preserve muscle.
✅ Strictly avoid forbidden foods.

Week 4

👉 Maximizing Fat Loss with Three 24-Hour Fasting Days

[Key Rules]

✅ Pick 3 non-consecutive days per week for 24-hour fasting (e.g., Mon, Wed, Fri OR Tue, Thu, Sat).
❌ Do NOT fast for two days in a row.
✅ On non-fasting days, never skip meals (4 meals per day).
✅ Rice (½ bowl) is now allowed for dinner.

[Action Plan]

🥗 Meals
✅ Dinner: Rice (½ bowl) is optional.

• Eat vegetables & protein first, then rice.
  ✅ Fruits are now allowed (1 per day, any type).
• Eat with breakfast or as dessert after lunch.
  ✅ Three 24-hour fasting days per week (not consecutive).
• Fasting Day Example:
  • Dinner (vegetables & protein, rice optional) → Fast for 24 hours → Next dinner
    ✅ Non-fasting day meal plan example:
• Breakfast: Protein shake + blueberries OR fruit
• Lunch: Regular meal with rice
• Afternoon Snack: Protein shake + handful of nuts
• Dinner: Vegetables + protein, rice optional
  ✅ One day per week (Sunday): Eat 3-4 meals from approved foods (protein shakes optional).
  ✅ Before & after HIIT or strength training:
• 1 small sweet potato or banana is allowed.
  ✅ 1 cup of black coffee in the morning is allowed (better if avoided).
  ✅ Follow the 14-hour fasting window between dinner and breakfast.
  ✅ Drink at least 8 cups of water daily.

😴 Sleep
✅ Maintain 7-8 hours of sleep (including 12 AM - 4 AM).
✅ Dim lights in the evening and avoid screens 1 hour before bed.
✅ A 20-minute nap is allowed.

🏃 Exercise
✅ Move every 30 minutes (light stretching or short walks).
✅ Increase workout intensity:

• 4+ workouts per week
• 20-60 minutes of high-intensity interval training (HIIT)
• Push harder each day.
  ✅ Strength training 3-4 times per week for best results.
  ✅ If you can’t go to the gym, do at least 5 stair climbs of 15+ floors per day.

[Approved Foods]

✅ All Week 3 foods, plus:
✅ Rice (½ bowl) for dinner (optional).
✅ Fruits (any type, 1 per day).
✅ Before & after HIIT or strength training:

• 1 small sweet potato or banana.

[Pro Tips for Fasting Days]

🟢 Think of fasting as activating stored energy, not deprivation.
🟢 Increase movement—walking & exercise maximize fat burn.
🟢 Supplements are optional on fasting days.
🟢 If hunger becomes too intense, stop at 20 hours and eat a protein shake or meal (but aim to complete the fast next time!).
🟢 Protein is crucial on non-fasting days—eat well before and after fasting to prevent muscle loss.

🚫 Forbidden Foods (Days 22-28)

❌ Sugars & High-Fructose Syrups (soda, sweetened coffee, juice, flavored milk, sugary yogurt, sweets, pastries, chocolate)
❌ Trans Fats (cakes, microwave popcorn, processed snacks, donuts, deep-fried foods)
❌ Alcohol
❌ Wheat-Based Foods (bread, cakes, noodles, ramen, pasta, black bean noodles)
❌ High-Saturated Fat Meats (pork belly, intestines)

✅ Final Check Before Entering Maintenance Phase

1️⃣ The Goal is NOT Just Weight Loss.

✅ Focus on fat loss & metabolic health improvement
✅ Check: Blood pressure, blood sugar, LDL cholesterol, HDL cholesterol, triglycerides, liver function, uric acid, insulin, HbA1c

2️⃣ If Metabolic Markers Are Not Yet Normal:

✅ Transition to maintenance and repeat the program later.
(You’ve already improved—don’t get discouraged!)

3️⃣ If Muscle Increased & Fat Significantly Decreased:

✅ Continue Week 3 or 4 methods.

4️⃣ If Muscle Mass Dropped in Week 4:

✅ 3-day fasting may be too much → Reduce to 1-2 times per week.

5️⃣ If Weight & Fat Loss Have Stalled:

✅ Enter maintenance phase → Let your body recover → Restart later.

🗓️ Maintenance Phase

👉 Maintaining Your Current Weight

[Key Rules]

✅ Maintain weight instead of losing more.

[Action Plan]

🥗 Meals
✅ Weigh yourself every morning.
✅ If weight increases, move more instead of eating less.
✅ 1 weekly 24-hour fast can help maintain weight.
✅ Finish dinner at least 3 hours before bed.
✅ Adjust carb intake based on activity level:

• More carbs on high-activity days.
• Fewer carbs on low-activity days.
  ✅ Weekends:
• 1 cheat meal per week (forbidden foods allowed).
  ✅ Prioritize protein in every meal.
  ✅ Limit fruit intake to 1-2 per day (avoid at night).
  ✅ Supplements are optional but reduce dosage compared to diet phase.

😴 Sleep
✅ Maintain at least 6+ hours per night.

🏃 Exercise
✅ Avoid long periods of sitting.
✅ Continue regular exercise consistently.

[Pro Tips for Long-Term Maintenance]

👉 How long should you maintain before restarting the program?

• It depends! If your metabolism recovers quickly, restart in 1-2 months.
  👉 If belly fat or weight increases, restart the program immediately.

[Food Guidelines for Maintenance]

Eat Every Meal:

🥗 Vegetables + High-quality protein
✅ Seaweed, mushrooms
✅ Lean proteins:

• Tofu, eggs, fish, seafood, chicken, lean beef/pork
  ✅ Healthy fats:
• Olive oil, coconut oil, avocado oil, perilla oil

Eat 1-2 Times Per Day:

🍚 Whole grains:

• Brown rice, mixed grains, lentils, quinoa
• White rice: ½ bowl per meal
  🍚 Adjust rice intake based on activity level:
• Active days: 2 meals with rice
• Less active days: 1 meal with rice

Eat Once Per Day:

🥛 Dairy & Nuts:

• Plain yogurt, cheese, unsweetened soy/milk (1-2 cups)
• Nuts (1 handful)
  🍠 Starchy carbs:
• Sweet potato OR fruit (1 per day)

Eat 1-2 Times Per Week:

🍷 Alcohol:

• Max 4 drinks for men, 2 for women
  🍝 Refined carbs:
• Whole wheat bread, noodles, pasta, fatty meats

Avoid as Much as Possible:

🚫 Sugary drinks, trans fats, processed meats.

Following this plan ensures long-term success without regaining weight. Are you ready to transition into maintenance? 💪🔥 Let me know your thoughts! ⬇️😊