What should I eat the first week of the carnivore diet? A Beginner's Guide

October 7, 2025 •

4 min read

Many people report experiencing a "keto flu" during the initial phase of the carnivore diet as their bodies adapt to using fat for fuel. Knowing what should I eat the first week of the carnivore diet is crucial for minimizing discomfort and setting yourself up for success.

Quick Summary

The first week of the carnivore diet involves simple animal-based foods like ground beef, eggs, and fatty cuts of meat to ease the transition. Hydration and electrolyte management are key to mitigating adaptation symptoms.

Key Points

Focus on Simple Foods: Stick to easily digestible options like fatty ground beef and eggs during the initial days to ease the digestive transition.
Prioritize Fatty Cuts of Meat: Opt for fattier meats like ribeye, pork belly, and chicken thighs to provide a consistent energy source as your body adapts to burning fat.
Hydrate and Replenish Electrolytes: Drink plenty of water and salt your food liberally. Consider sipping bone broth to help combat the headaches and fatigue associated with fluid loss.
Incorporate Nutrient-Dense Organs Gradually: Add small amounts of organ meats like liver to your diet for essential nutrients, but introduce them slowly to gauge your tolerance.
Prioritize Rest and Reduce Intense Activity: Allow your body time to adapt by listening to its cues. Light exercise is fine, but intense workouts may need to be scaled back during the first week.
Don't Force Fasting: Eat as often as you feel hungry, prioritizing satiation. Focusing on meal timing or restriction is unnecessary and counterproductive during the initial adaptation period.
Avoid All Plant-Based Foods: Remember the strict rule of the carnivore diet and avoid fruits, vegetables, grains, nuts, and seeds, as these will disrupt your metabolic transition.

Understanding the First-Week Adjustment

When you start the carnivore diet, your body undergoes a significant metabolic shift, transitioning from using carbohydrates for energy to burning fat. This process, often called "carnivore adaptation" or "keto flu," can cause temporary side effects as your system adjusts. During the first week, it is common to experience symptoms such as headaches, fatigue, brain fog, and muscle cramps. Some people also report digestive changes, including constipation or diarrhea, as their gut microbiome adapts to the absence of fiber. These side effects are usually short-lived and manageable with proper hydration, rest, and strategic food choices. Focusing on simple, nutrient-dense, and satisfying animal products is the best approach to ease this transition.

The Core Food List for Your First Week

To make your first week as smooth as possible, keep your food choices simple and nourishing. The following categories represent your primary sources of food, with a focus on ease of digestion and maximizing fat intake for energy.

Beef: A cornerstone of the carnivore diet due to its affordability and nutrient density. Ground beef is a great, easy-to-digest option for the first few days, while fattier cuts like ribeye, chuck roast, and brisket are excellent for providing sustained energy.
Other Meats: Pork, lamb, and bison are also great choices. Fatty cuts such as pork belly and lamb chops will provide a good source of energy.
Poultry: Fattier parts of chicken and turkey, like thighs and wings, are preferable over leaner breast meat during the adaptation phase.
Seafood: Include fatty fish like salmon, sardines, and mackerel, which are rich in omega-3 fatty acids. Shellfish like shrimp and scallops can also add variety.
Eggs: A perfect, complete protein source that is easy on the digestive system. Eggs can be prepared in many ways, including scrambled, fried, or hard-boiled.
Organ Meats: Nutrient powerhouses like liver and kidney are highly recommended but should be introduced slowly and in small amounts. They provide essential vitamins and minerals that can be low in a purely muscle-meat-based diet.
Fats: Use animal fats like tallow, lard, and butter for cooking. If you tolerate dairy, ghee is also a great option.
Dairy (If Tolerated): Some people include low-lactose dairy like hard cheeses and heavy cream. However, many choose to eliminate dairy initially to see if they have a sensitivity.

First Week Sample Meal Plan

This sample plan prioritizes simple, satisfying meals to help your body adapt without unnecessary complexity. Eat until you are full, and don't be afraid to eat two or three meals a day, or even just one large meal (OMAD) if your body naturally adjusts that way.

Day 1: Breakfast: Scrambled eggs cooked in butter. Lunch: Ribeye steak seasoned with salt. Dinner: Ground beef patties.
Day 2: Breakfast: Bacon and eggs. Lunch: Leftover beef patties. Dinner: Baked trout with melted butter.
Day 3: Breakfast: Hard-boiled eggs and a small amount of liver. Lunch: Pork chops. Dinner: Slow-cooked chuck roast.
Day 4: Breakfast: Scrambled eggs with a small amount of hard cheese (if tolerated). Lunch: Leftover chuck roast. Dinner: Salmon fillet pan-seared in tallow.
Day 5: Breakfast: Pork sausage patties and fried eggs. Lunch: Ground beef patties. Dinner: Chicken wings cooked until crispy.
Day 6: Breakfast: Eggs cooked in ghee. Lunch: Lamb chops. Dinner: Shrimp sautéed in butter.
Day 7: Breakfast: Smoked salmon and eggs. Lunch: Leftover lamb chops. Dinner: Brisket cooked until tender.

Navigating the 'Carnivore Flu'

The adaptation phase can be challenging, but these strategies can help minimize discomfort:

Hydration and Electrolytes: Dehydration and electrolyte imbalances are common side effects of carbohydrate elimination. Drink plenty of water throughout the day. Add extra salt to your meals and consider sipping on bone broth to replenish electrolytes.
Listen to Your Body: Don't push yourself with intense workouts during the first one to two weeks. Instead, focus on light activity like walking and prioritize rest as your body adjusts. Sleep is crucial for recovery and adaptation.
Keep it Simple: Avoid overcomplicating your meals or forcing fasting too early. Your primary goal is to provide your body with the fuel it needs. Focus on satiating, simple meals and worry about variety later. This reduces stress and helps you stay consistent.
Eat Enough Fat: Your body is now running on fat for energy, so under-eating fat will lead to fatigue and cravings. Opt for fattier cuts of meat and use ample cooking fats like butter or tallow to feel satisfied and energized.

Carnivore Diet vs. Other Low-Carb Diets


Feature	Carnivore Diet	Ketogenic Diet	Paleo Diet
Allowed Foods	Animal products only (meat, eggs, fish, some dairy)	Animal products, low-carb vegetables, some berries, nuts, seeds	Meat, fish, eggs, fruits, vegetables, nuts, seeds
Excluded Foods	All plant foods	Grains, legumes, sugar, most fruits	Grains, legumes, dairy, processed foods
Carb Intake	Near zero	Very low (under 50g/day)	Low to moderate
Primary Energy Source	Fat and protein	Fat (ketosis)	Mix of protein, fat, and carbs
Adaptation Period	2-4 weeks (carnivore flu)	1-2 weeks (keto flu)	Minimal, often a smoother transition

Conclusion: Setting the Stage for Success

Beginning the carnivore diet is a significant change for your body, but with the right approach, the first week can be manageable. By focusing on simple, fatty animal foods, you can provide your body with the fuel it needs to adapt to ketosis. Prioritizing hydration and electrolytes is key to mitigating common transitional symptoms like headaches and fatigue. Listening to your body, resting when needed, and not overcomplicating your meals will set you up for long-term success. While a variety of animal-based foods are available, sticking to a consistent core set initially will simplify meal planning and help you focus on your body's signals. As with any restrictive eating plan, it is advisable to consult a healthcare professional, especially if you have pre-existing health conditions or concerns. The Cleveland Clinic also offers valuable insights on the diet's safety and risks to consider before you begin.

Frequently Asked Questions

During the first week, many people experience symptoms known as the "carnivore flu," including fatigue, headaches, cravings, and digestive changes such as diarrhea or constipation.

There is no specific calorie or portion guidance; proponents suggest eating until you are full and satisfied. Focusing on fattier cuts of meat is recommended for sufficient energy.

Some people include low-lactose dairy like butter, ghee, and hard cheeses, but many find it best to eliminate dairy during the initial adaptation phase to better understand their tolerances.

Bone broth is highly recommended as a source of electrolytes and hydration, which can help alleviate symptoms of the "carnivore flu".

Strict carnivore dieters typically only use salt. However, some variants allow for simple, carb-free spices like black pepper.

Ensuring you eat enough fat is the most effective way to manage cravings and maintain energy. Drinking plenty of water and focusing on satisfying, protein-rich meals can also help.

It is best to stick to light exercise like walking during the initial adaptation period. Your body is undergoing a major transition, and intense workouts can add unnecessary stress.

The most straightforward version, often called the "beef, salt, and water" method, involves eating only ground beef or steak, seasoning with salt, and drinking water.