What is the Ketogenic Diet?
The ketogenic diet prioritizes high fat, moderate protein, and very low carbohydrates. Typical keto macronutrient ratios are:
- 60-75% of calories from fat
- 15-30% of calories from protein
- 5-10% of calories from carbs
This specific balance helps shift your body into ketosis—a metabolic state where fat replaces glucose as the primary fuel source. For most, limiting carbs to under 50 grams daily (20-25 grams net) is key to achieving ketosis, though exact needs vary based on individual factors like activity level and goals.
While calorie counting isn’t mandatory on keto, tracking can help if you’re looking to lose weight or reduce body fat. Download our free app to simplify tracking!
Understanding Your Maintenance Level (Total Energy Expenditure - TEE)
Our keto calculator is open-source to ensure transparency and accuracy. You can check out the source code for it on GitHub.
To maintain body weight, calculating your Maintenance Level (also known as Total Energy Expenditure or TEE) is essential. TEE reflects the calories needed to sustain your weight and can be calculated with the following formula:
Maintenance Level = BMR + TEA + TEF
- BMR (Basal Metabolic Rate): Baseline calories for essential functions like breathing and digestion, calculated using the Mifflin - St Jeor Formula, one of the most accurate methods.
- TEA (Thermic Effect of Activity): Calories burned through all physical activity, from daily movement to exercise.
- TEF (Thermic Effect of Feeding): The metabolic increase after eating, especially from protein. TEF averages 10% on a keto diet.
Find Your Activity Level
Your activity level determines the TEA portion of your calorie needs. Here are the five activity levels, adapted from Lyle McDonald's approach, with adjusted multipliers for accuracy:
- Sedentary: Little to no exercise. This typically includes light walking and most office jobs like receptionists, graphic designers, accountants, and customer service workers. Multiplier: 1.2
- Lightly Active: Light exercise 1-3 times a week. This includes activities such as walking, light cycling, or jobs that require some physical movement (e.g., teachers, nurses). Multiplier: 1.375
- Moderately Active: Moderate exercise 3-5 times per week. This level includes moderate cardio and strength training, as well as moderately active jobs like waitstaff or cooks. Multiplier: 1.55
- Very Active: Hard exercise 5 or more times a week. This category is for those who engage in intense cardio, weight training, and have physically demanding jobs like construction workers, farmers, or landscapers. Multiplier: 1.725
- Athletes / Bodybuilders: Individuals who perform intense, daily exercise or professional-level training (e.g., high-intensity interval training, heavy lifting). Multiplier: 1.9
Knowing your activity level helps you calculate your Total Energy Expenditure accurately, allowing you to tailor your ketogenic diet to fit your weight loss, maintenance, or muscle gain goals.
Carbohydrate Intake on the Ketogenic Diet
Restricting carbohydrates is fundamental to the keto diet. This restriction shifts the body from burning glucose to burning fat for energy—the core process of ketosis. Ketosis supports fat loss and offers therapeutic benefits for various health conditions.
Total Carbs vs. Net Carbs: Which to Track?
Two approaches exist for measuring carbs on keto:
- Total Carbs: All carbohydrates, including fiber and sugar alcohols.
- Net Carbs: Total carbs minus fiber and certain sugar alcohols (these don’t impact blood sugar or ketosis).
Most people on keto focus on net carbs because they offer a more flexible way to track carbohydrate intake, especially when consuming high-fiber foods like vegetables and nuts. You can read more about this here: Should I Count Net Carbs? Separating Facts from Opinions
On a typical ketogenic diet, it's recommended to consume 20-25 grams of net carbs per day (or 30-50 grams of total carbs) to enter and stay in ketosis.
Therapeutic Low-Carb Intake for Specific Health Conditions
For those managing certain health conditions, such as type 2 diabetes, epilepsy, or neurological disorders like Alzheimer’s or Parkinson’s, the level of carbohydrate restriction may need to be even stricter. Therapeutic ketogenic diets, particularly for epilepsy management, often require less than 20 grams of total carbs per day to maximize the benefits of ketosis.
The exact carbohydrate limit depends on the individual and the specific condition being treated. In these cases, it's crucial to work with a healthcare provider to tailor the diet appropriately.
By keeping your carbohydrate intake low and focusing on nutrient-dense, whole foods, you can maintain ketosis and experience the full benefits of the ketogenic diet, whether your goal is weight loss or improved health.
Protein Intake on a Ketogenic Diet
Protein is crucial in keto, maintaining muscle mass, promoting satiety, and supporting overall health. Insufficient protein can increase hunger, potentially leading to overeating, and muscle loss, which may slow metabolism.
The ideal protein intake depends on your lean body mass (total weight minus body fat) and your activity level. According to Volek and Phinney (authors of The Art and Science of Low Carbohydrate Performance), your daily protein intake should be between 0.6 and 1.0 grams per pound of lean body mass (1.3 to 2.2 grams per kilogram).
Example
If you weigh 160 pounds and have 30% body fat, your lean mass is:
- 160 lbs - 30% = 112 lbs of lean mass.
Your protein intake would then be:
- 112 lbs x 0.6 = 67 grams of protein per day (minimum)
- 112 lbs x 1.0 = 112 grams of protein per day (maximum)
Protein Intake by Activity Level
Adjust your protein intake according to your activity level:
- Sedentary (no exercise): 0.6 grams per pound of lean body mass.
- Lightly Active (light exercise 1-3 times weekly): 0.7 grams per pound.
- Moderately Active (moderate exercise 3-5 times weekly): 0.8 grams per pound.
- Very Active (intense exercise 5+ times weekly): 0.9 grams per pound.
- Athletes/Bodybuilders (professional training): 1.0 gram per pound.
Protein Intake Is Consistent Across Goals
Whether your goal is weight loss, maintenance, or muscle gain, your protein intake on a ketogenic diet remains the same. It's only the amount of fat you adjust based on your overall calorie needs. Adequate protein intake is critical for preserving muscle mass, especially when you're in a calorie deficit for fat loss.
Protein Intake During the First 3 Weeks
Getting the right amount of protein and achieving ketosis are both crucial for maximizing fat loss while preserving muscle mass on a ketogenic diet. However, during the first few weeks (typically up to 3 weeks), your body undergoes an adaptation period, known as keto-adaptation. During this phase, your body may experience nitrogen losses, especially if your daily carb intake is very low.
When your carbohydrate intake is significantly reduced, your body may begin converting protein into glucose (a process called gluconeogenesis). Since about 16% of protein consists of nitrogen, this can lead to muscle loss, which may cause a decrease in your metabolic rate and negatively affect fat loss.
For those consuming very close to zero carbohydrates, a temporary increase in protein intake might be necessary. This approach is called a Protein-Sparing Modified Fast (PSMF) and is particularly relevant for those on a zero-carb or extremely low-carb diet. Keep in mind that this level of carb restriction is rare for most people following a standard ketogenic diet.
According to Lyle McDonald:
How Many Carbs Do I Need to Spare Protein Loss?
Early research on starvation and low-carb diets found that as little as 15 grams of carbohydrates per day can limit nitrogen loss. Increasing carbohydrate intake to 50 grams per day dramatically reduces the need for the body to use amino acids for gluconeogenesis. This happens through two mechanisms:
- Maintaining blood glucose and insulin at higher levels, which inhibits cortisol release.
- Providing glucose for the brain, thus reducing the need to break down body protein.
Therefore, to prevent muscle loss, you can either increase your protein intake or consume slightly more carbohydrates (15-50 grams per day). Both approaches help limit the body’s need to break down protein.
What's Protein Boost?
Protein boost is designed with flexibility in mind, allowing you to adjust your protein intake upwards easily, which can be beneficial if you're looking to support muscle health, enhance satiety, or accommodate increased physical activity levels.
Do You Need a Protein Boost? Let's Find Out
Whether you need a protein boost isn't a simple yes or no question—it depends on your lifestyle, diet, and health goals. Here’s a concise guide to help you decide:
- Are you regularly engaging in strength training or endurance activities? If yes, your body may require more protein to repair and grow muscle tissue. A protein boost can be beneficial.
- Do you often find yourself feeling hungry between meals? Protein can increase satiety, helping you feel fuller for longer. Consider increasing your intake to manage hunger and support weight management.
- Are you trying to lose weight without losing muscle? Higher protein intake can help preserve lean muscle mass during calorie restriction, making a protein boost advisable.
Why Start with a 15% Boost?
For those on a keto diet, fine-tuning protein intake can make a significant difference. A 15% increase is moderate enough to benefit those needing a bit more protein. It's a great way to test how slightly more protein affects your body. Remember, this is a customizable feature. Start with the 15% boost and adjust based on your body’s response, goals, and activity level. It’s all about finding what works best for you.
Will too Much Protein Kick Me Out of Ketosis?
If you're on a keto diet, you might worry that extra protein could interrupt ketosis due to gluconeogenesis, where your body turns protein into glucose. It's important to know that this process is demand-driven, not automatic with high protein intake. Your body smartly uses gluconeogenesis to maintain necessary blood sugar levels, especially when carbs are scarce, ensuring everything runs smoothly. So, adding a bit more protein to your diet won’t necessarily push you out of ketosis. It's all about finding the right balance to support muscle health and your diet goals, keeping you on track with your keto journey.
Remember, the goal is to meet your body's needs without going to extremes. Balance is key. To learn more about high-protein diets, check out this guide: High-Protein Diets. Is More Protein Actually Better?
How to Find Your Body Fat Percentage
There are several ways of varying accuracy and complexity for estimating your body fat.
1. Using Skinfold Calipers (preferred method)
To get a good estimate of your body fat percentage, use our Body Fat Calculator (Jackson / Pollock method). For the most accurate results, use a formula best suited for your needs (read more about other caliper methods).
2. Body measurement method
Not the most accurate but can give you a rough idea - it uses your body measurements (waist, hips and neck). Here is a good on-line calculator you can use.
3. Using DEXA (Dual-energy X-ray absorptiometry)
4. Visual estimates using comparison illustrations - see below for comparison charts.
Fat Intake on a Ketogenic Diet
On a ketogenic diet, fat is your primary energy source. Since carbohydrates are restricted, your body turns to fat for fuel, both from your diet and stored body fat. This shift is key to achieving and maintaining ketosis, where fat is converted into ketones to provide energy.
Role of Fat as the Primary Energy Source
Fat on a ketogenic diet is typically making up 70-75% of your daily calorie intake. The type of fat you consume is also important. Prioritize healthy, natural fats such as:
- Animal fats (from grass-fed meats, butter, ghee, etc.)
- Plant-based fats (avocados, olive oil, coconut oil, and nuts)
Eating fat keeps you feeling full and satisfied, helping to reduce cravings and make it easier to stick to your daily macronutrient goals.
Adjusting Fat Intake for Weight Loss
On keto, fat serves as the primary energy source and helps you control calorie intake. For weight loss, aim to create a calorie deficit by reducing fat intake moderately, prompting your body to use stored fat for energy.
To lose weight, you’ll need to create a calorie deficit—meaning you consume fewer calories than your body needs to maintain its current weight. Since protein intake remains constant and carbohydrate intake is minimal, you’ll need to adjust fat intake to control your calorie levels.
Here’s how it works:
- If your goal is weight loss, reduce your fat intake slightly to create a moderate calorie deficit. You’ll then burn stored body fat for energy.
- If your goal is weight maintenance or muscle gain, your fat intake can be higher to meet your overall calorie needs without creating a deficit.
The key to long-term success is finding a balance. While fat is essential on a ketogenic diet, eating excess fat won’t necessarily speed up fat loss. Your body will burn dietary fat before tapping into stored fat, so it’s important to avoid overeating fat just to “meet your macros” if weight loss is your goal.
Finally, you may think that the bigger the calorie deficit, the faster the weight loss. However, for best long term results a moderate deficit is recommended. Even for active individuals, best results are achieved with moderate caloric deficits.
Want to know more about adjusting your macros? Read this: Struggling to Hit Your Macros? Here's the Solution
Minimum Calorie Intake
Understanding your minimum calorie intake is essential for achieving maximum fat loss while maintaining muscle mass and overall health. Several factors determine how low you can safely reduce your calorie intake:
Risks of Eating Below Minimum Calorie Intake
The minimum calorie intake is the maximum safe rate for metabolizing fat. Consuming fewer calories than this limit can cause several negative effects, including:
To avoid these side effects and support sustainable fat loss, it’s important to stay above your minimum calorie intake and focus on a moderate calorie deficit for best long-term results.
Additional Tips
As you progress on your ketogenic diet, it's important to keep adjusting your approach based on your changing body composition and goals. Here are some tips to help you stay on track:
Recalculate Your Macronutrients Regularly
As your weight and body fat percentage change, so will your macronutrient needs. It's a good idea to recalculate your macronutrient intake every few weeks or when you notice changes in your weight or activity level. This ensures you’re still in line with your goals, whether you’re aiming for fat loss, maintenance, or muscle gain.
Focus on Fat Loss, Not Just Weight Loss
Don’t rely solely on the scale to measure progress - don't weigh yourself more than once a week. Weight fluctuations can occur due to water retention, hormonal changes, or increased muscle mass. Instead, focus on fat loss by using tools like body tape measurements, progress photos, or body fat calipers. Fat loss is the key to long-term success, especially when you're aiming to maintain muscle mass while shedding excess fat.
Resources & Tools
To help you stay on track with your ketogenic diet, there are several useful tools and resources available:
By staying informed and using these tools, you’ll have the guidance and support you need to succeed on your ketogenic journey.