What should I eat the first week of Atkins? A Guide to the Induction Phase

October 18, 2025 •

4 min read

According to the official Atkins website, the Induction phase is a brief, jump-start period that helps your body switch from burning carbohydrates to fat for fuel. This means a significant dietary shift, so understanding exactly what should I eat the first week of Atkins? is crucial for success.

Quick Summary

The first week of the Atkins diet, known as the Induction phase, involves restricting net carbs to under 20 grams per day. Focus on high-protein foods like meat, fish, eggs, and cheese, along with non-starchy, high-fiber vegetables and healthy fats to trigger ketosis.

Key Points

Restrict Net Carbs: In the first week of Atkins (Induction), limit your net carbohydrate intake to under 20 grams per day to initiate ketosis.
Prioritize Protein: Build your meals around protein sources like meat, poultry, eggs, and fish to stay full and satisfied.
Embrace Non-Starchy Vegetables: Include plenty of foundation vegetables like leafy greens, broccoli, and cauliflower for essential nutrients and fiber.
Focus on Healthy Fats: Incorporate healthy fats from sources like olive oil, avocado, and butter to provide your body with its new energy source.
Avoid High-Carb Foods: Strictly avoid sugars, grains, starchy vegetables, and most fruits during the Induction phase.
Stay Hydrated and Electrolyte-Conscious: Drink plenty of water and replenish electrolytes to minimize symptoms of the 'keto flu'.
Plan Your Meals: Create a meal plan for the week to help you stick to the limited food list and avoid temptation.

Understanding the Atkins Induction Phase

The Atkins diet, particularly in its original form (Atkins 20), begins with a highly restrictive initial phase known as Induction. This phase lasts for at least two weeks, though the first seven days are the most critical for adapting to a low-carbohydrate lifestyle. During this time, your body undergoes a metabolic shift into a state of ketosis, where it begins burning fat for energy instead of glucose from carbohydrates.

The primary rule of this phase is to limit your net carbohydrate intake to fewer than 20 grams per day. Net carbs are calculated by subtracting fiber grams from total carbohydrate grams. To stay within this limit, you must be very selective about your food choices. The bulk of your diet will consist of protein, healthy fats, and low-carb vegetables.

What to Eat: A Comprehensive Guide for Week One

Protein Sources

Protein is a cornerstone of the Atkins diet, helping you feel full and satisfied. You can enjoy various meats, poultry, fish, and eggs throughout the day.

Meat: Beef, pork, lamb, and bacon are all acceptable. However, be cautious with processed meats like hot dogs and sausages, as some contain added sugars.
Poultry: Chicken, turkey, and other fowl are excellent protein sources.
Eggs: Enjoy eggs prepared in any style—scrambled, fried, or as an omelet. Eggs are rich in protein and other nutrients.
Fish and Shellfish: Fatty fish like salmon, trout, and mackerel provide healthy fats and protein. Shellfish like shrimp and crab are also allowed.

Non-Starchy Vegetables

While carbs are limited, you must still consume vegetables, as they are a primary source of fiber and essential nutrients. You should aim to get 12–15 grams of your daily net carbs from these “foundation vegetables”.

Leafy Greens: Spinach, kale, romaine lettuce, and arugula are low-carb staples.
Cruciferous Vegetables: Broccoli, cauliflower, Brussels sprouts, and cabbage are highly versatile. Cauliflower can even be used as a substitute for rice or mashed potatoes.
Other Low-Carb Veggies: Asparagus, celery, mushrooms, cucumbers, and peppers are all great options.

Healthy Fats and Oils

Fat is your body’s new primary fuel source during Induction, so incorporating healthy fats is essential for energy and satiety.

Oils: Olive oil, avocado oil, and coconut oil are great for cooking and salad dressings.
Fats: Butter and mayonnaise (sugar-free) can add flavor to your meals.
Avocado: This is a great source of healthy fats and fiber, but its carb count should be managed carefully.

Full-Fat Dairy

Cheese and other full-fat dairy products are allowed in moderation during the Induction phase.

Cheese: Full-fat cheese such as cheddar, Swiss, mozzarella, and feta are allowed, up to 4 ounces per day.
Cream: Heavy cream and sour cream can be used in small amounts.

What to Avoid: The First-Week Restrictions

During Induction, it’s just as important to know what to avoid as what to eat. Eliminating high-carb foods is key to entering and maintaining ketosis.

Sugars: This includes obvious culprits like candy, cakes, and soda, but also hidden sugars in sauces and dressings.
Grains: All grains, including bread, pasta, rice, and cereal, are off-limits.
Starchy Vegetables: Avoid potatoes, sweet potatoes, corn, and peas.
High-Carb Fruits: Most fruits are not allowed during Induction, with the exception of avocado and olives.
Legumes: Beans, lentils, and chickpeas are restricted during this phase.
Alcohol: Avoid alcoholic beverages, which can stall weight loss.

Sample Meal Plan for Your First Week


	Breakfast	Lunch	Dinner
Day 1	2 scrambled eggs with spinach and feta cheese	Grilled chicken salad with romaine lettuce, cucumber, and a creamy, sugar-free dressing	Baked salmon with roasted broccoli and asparagus
Day 2	Bacon and eggs fried in butter	Tuna salad (made with mayonnaise) served in avocado halves	Beef stir-fry with broccoli, bok choy, and onion
Day 3	Ham and cheese omelet with sliced avocado	Turkey and cheese roll-ups with a side of celery sticks	Ground beef burger (no bun) with lettuce, tomato, and cheese
Day 4	Scrambled eggs with diced bell peppers and cheddar cheese	Leftover turkey and cheese roll-ups	Pork chops with a side of garlic-sautéed kale
Day 5	2 fried eggs with bacon	Large salad with grilled chicken, avocado, and olive oil dressing	Chicken wings roasted in garlic butter with a side of steamed green beans
Day 6	Egg and mushroom frittata	Shrimp salad with mixed greens and a lemon-oil dressing	Zucchini noodles with ground meat marinara (no sugar added)
Day 7	Smoked salmon and cream cheese wrapped in cucumber	Leftover zucchini and meat sauce	Steak with a side of pan-seared mushrooms and cauliflower mash

Managing the Transition: Dealing with the 'Keto Flu'

As your body adapts to burning fat instead of carbs, you may experience a temporary period known as the “keto flu.” Symptoms can include fatigue, headaches, irritability, and muscle cramps. To mitigate these effects:

Stay Hydrated: Drink plenty of water throughout the day to combat dehydration.
Replenish Electrolytes: Low electrolyte levels can cause flu-like symptoms. Adding salt to your food and consuming potassium-rich foods like avocados and leafy greens can help. Bone broth is also a great option.
Listen to Your Body: Rest when you feel fatigued. Your energy levels will normalize as your body adjusts.
Ease In: If symptoms are severe, consider a slower transition by reducing carbs gradually over a few days.

Conclusion

The first week of the Atkins diet, or Induction, is a pivotal stage that requires discipline and careful meal planning. By focusing on an eating plan rich in proteins, healthy fats, and low-carb vegetables, you can successfully kick-start the metabolic process of ketosis and begin your weight loss journey. Staying hydrated and replenishing electrolytes will help manage any transitional symptoms, paving the way for a successful low-carb lifestyle. As you progress, you will gradually reintroduce more carbohydrates, but for now, sticking to the foundational foods is your key to success.

Frequently Asked Questions

No, most fruits are not allowed during the first week of the Atkins diet (Induction phase) due to their high sugar content. You will reintroduce fruits like berries in later phases.

During the Induction phase, you should eat non-starchy, high-fiber vegetables, including leafy greens like spinach and kale, and cruciferous vegetables like broccoli and cauliflower.

Yes, bacon is allowed in the first week of Atkins. However, you should choose a variety without added sugar and be mindful of processed varieties.

You should primarily drink water, but you can also have unsweetened coffee, tea, and clear broths. Sugar-sweetened drinks and alcohol should be avoided.

Net carbs are calculated by subtracting the fiber content from the total carbohydrates in a food. In the first week of Atkins, you aim for fewer than 20 grams of net carbs per day.

Yes, you can eat full-fat cheese during the Induction phase. Common examples include cheddar, Swiss, and mozzarella, but portion size should be limited to about 4 ounces per day.

Some people experience a temporary 'keto flu' as their body switches from burning carbs to fat. Symptoms can include fatigue and headaches. Staying hydrated and replenishing electrolytes can help manage this.