How Many Grams of Protein for Weight Loss Calculator

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How Many Grams of Protein for Weight Loss Calculator

Calculate your optimal daily protein intake to support weight loss goals.

Enter your current body weight in kilograms (kg).
Sedentary (little to no exercise) Lightly active (light exercise/sports 1-3 days/week) Moderately active (moderate exercise/sports 3-5 days/week) Very active (hard exercise/sports 6-7 days a week) Extra active (very hard exercise/sports & physical job or 2x training)
Choose the option that best describes your average weekly physical activity.
Harris-Benedict (Revised) Mifflin-St Jeor
Select the formula used to estimate your Basal Metabolic Rate (BMR).
Enter your target weight loss in kilograms per week (e.g., 0.5 kg).

Your Protein Recommendations

25g – 35g (Recommended Range)
Estimated Daily Calorie Deficit Needed: kcal
Estimated Total Daily Calories: kcal
Protein Range (g/kg body weight): g/kg
Formula Explanation:

We first estimate your Basal Metabolic Rate (BMR) using either the Mifflin-St Jeor or Revised Harris-Benedict equation, factoring in your weight, age, sex, and height. This BMR is then multiplied by your activity level to get your Total Daily Energy Expenditure (TDEE). To lose weight, a calorie deficit is needed. For a 0.5kg weekly loss, a deficit of approximately 500 calories/day is targeted. Your protein intake is then set to a range of 1.6 to 2.2 grams per kilogram of body weight, which is generally recommended for satiety and muscle preservation during weight loss.

Calorie & Protein Breakdown

Estimated Daily Calorie and Protein Needs

Variable Table

Key Variables and Their Ranges
Variable Meaning Unit Typical Range
Body Weight Current weight of the individual kg 30 – 200+
Activity Level Multiplier Factor representing daily energy expenditure based on activity Multiplier 1.2 – 1.9
BMR Basal Metabolic Rate (calories burned at rest) kcal/day 1000 – 2500+
TDEE Total Daily Energy Expenditure kcal/day 1200 – 3500+
Calorie Deficit Calories to reduce daily intake for weight loss kcal/day 250 – 1000
Target Protein Recommended daily protein intake grams/day 50 – 300+

What is How Many Grams of Protein for Weight Loss Calculator?

The How Many Grams of Protein for Weight Loss Calculator is a specialized tool designed to help individuals determine an appropriate daily protein intake to support their weight loss journey. It takes into account various personal metrics to provide a tailored recommendation, moving beyond generic advice. This calculator is particularly useful for those looking to lose weight efficiently while preserving lean muscle mass and managing hunger effectively, making the process of weight loss more sustainable. Understanding your specific protein needs is a cornerstone of successful dietary changes, and this tool demystifies that aspect of nutrition. The core idea is that sufficient protein intake during a calorie deficit is crucial for satiety, thermogenesis, and preventing muscle breakdown, all of which are vital for effective and healthy weight loss. Many people embarking on a weight loss program often underestimate their protein requirements, leading to increased hunger and muscle loss, which can derail their efforts. This calculator aims to prevent that by providing a data-driven approach to protein intake for weight loss.

Who Should Use This Calculator?

Anyone aiming to lose weight can benefit from this calculator. This includes individuals who are:

  • Looking for a structured approach to their diet.
  • Concerned about preserving muscle mass while losing fat.
  • Experiencing persistent hunger on their current weight loss plan.
  • Seeking to optimize their metabolism for fat burning.
  • Trying to understand the role of macronutrients in weight management.
  • Athletes or fitness enthusiasts aiming for body recomposition.

Common Misconceptions About Protein for Weight Loss

Several myths surround protein intake and weight loss. One common misconception is that eating more protein automatically leads to weight gain due to its calorie content. While protein does have calories, its thermic effect (calories burned during digestion) is higher than that of fats or carbohydrates, and it is highly satiating, which can paradoxically lead to lower overall calorie intake. Another myth is that a very high protein intake is necessary for everyone. While increased protein is beneficial, the optimal amount varies based on individual factors. Our calculator helps to delineate a more appropriate range, avoiding excessive or insufficient intake for weight loss.

How Many Grams of Protein for Weight Loss Calculator Formula and Mathematical Explanation

The calculation involves several steps to arrive at a personalized protein recommendation. The primary goal is to establish a suitable calorie deficit and ensure adequate protein intake to support this deficit effectively. The formula leverages established metabolic rate calculations and general nutritional guidelines for weight loss.

Step-by-Step Derivation:

  1. Basal Metabolic Rate (BMR) Calculation: The calculator first estimates your BMR, which is the number of calories your body burns at rest to maintain basic functions. It uses either the Revised Harris-Benedict equation or the Mifflin-St Jeor equation, which are standard in nutritional science.
    • Mifflin-St Jeor Equation:
      • For Men: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
      • For Women: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
      *(Note: For this calculator, we'll simplify and focus on inputs available, often age/sex/height are abstracted into the activity level multiplier for user-friendliness in online tools)*
    • Revised Harris-Benedict Equation:
      • For Men: BMR = (13.397 × weight in kg) + (4.799 × height in cm) – (5.677 × age in years) + 88.362
      • For Women: BMR = (9.247 × weight in kg) + (3.098 × height in cm) – (4.330 × age in years) + 447.593
      *(Note: Similar to Mifflin-St Jeor, age/sex/height are often simplified in web calculators.)*
    *For simplicity in this calculator, we assume a standard male/female calculation based on common defaults if age/sex/height aren't primary inputs, or rely on the user's weight and activity level to infer an approximate TDEE.*
  2. Total Daily Energy Expenditure (TDEE) Calculation: Your BMR is then multiplied by an activity factor to estimate your TDEE – the total calories you burn in a day, including all activities.
    TDEE = BMR × Activity Level Multiplier
  3. Calorie Deficit for Weight Loss: To lose weight, you need to consume fewer calories than your TDEE. A common target is a deficit of 500-1000 calories per day to lose 1-2 pounds (0.5-1 kg) per week. The calculator determines the deficit based on your stated goal.
    Target Deficit = Goal (kg/week) × 7700 kcal/kg (approx. calories in 1 kg of fat) / 7 days/week
    This calculates the daily deficit needed. For example, 0.5 kg/week requires ~550 kcal/day deficit.
  4. Target Calorie Intake:
    Target Calorie Intake = TDEE - Target Deficit
  5. Protein Intake Calculation: For weight loss, a higher protein intake is generally recommended to preserve muscle mass and increase satiety. A common range is 1.6 to 2.2 grams of protein per kilogram of body weight.
    Minimum Protein = Body Weight (kg) × 1.6 g/kg
    Maximum Protein = Body Weight (kg) × 2.2 g/kg
    The calculator displays this range.

Variable Explanations:

Variables Used in the Calculation
Variable Meaning Unit Typical Range
Body Weight The individual's current body weight. kg 30 – 200+
Activity Level Multiplier A numerical factor representing the intensity and frequency of physical activity. Multiplier 1.2 (Sedentary) to 1.9 (Extra Active)
BMR Method Specifies which standard formula (Mifflin-St Jeor or Harris-Benedict) to use for BMR estimation. Formula Name Mifflin-St Jeor, Harris-Benedict
Weight Loss Goal The desired rate of weight loss per week. kg/week 0.1 – 1.5
Estimated Daily Calorie Deficit The number of calories to subtract from TDEE to achieve the weight loss goal. kcal/day ~100 – ~1100
Estimated Total Daily Calories The target calorie intake to achieve weight loss. kcal/day Varies based on TDEE and deficit.
Protein Range (g/kg body weight) The calculated minimum and maximum recommended daily protein intake based on body weight. g/kg 1.6 – 2.2

Practical Examples (Real-World Use Cases)

Let's illustrate how the calculator works with two distinct individuals:

Example 1: Sarah, a Moderately Active Office Worker

  • Inputs:
    • Body Weight: 75 kg
    • Activity Level: Moderately active (1.55)
    • BMR Method: Mifflin-St Jeor
    • Weight Loss Goal: 0.5 kg per week
  • Calculations:
    • Assuming a standard BMR calculation for a woman of average height/age leading to ~1600 kcal BMR.
    • TDEE = 1600 kcal × 1.55 = 2480 kcal (Estimated Total Daily Calories)
    • Target Deficit = 0.5 kg/week × 7700 kcal/kg / 7 days = ~550 kcal/day
    • Target Calorie Intake = 2480 kcal – 550 kcal = 1930 kcal
    • Protein Range:
      • Min: 75 kg × 1.6 g/kg = 120 g
      • Max: 75 kg × 2.2 g/kg = 165 g
  • Calculator Output:
    • Primary Result: 120g – 165g
    • Estimated Daily Calorie Deficit Needed: ~550 kcal
    • Estimated Total Daily Calories: ~1930 kcal
    • Protein Range (g/kg body weight): 1.6g – 2.2g/kg
  • Interpretation: Sarah should aim for a daily intake of around 1930 calories, with her protein intake falling between 120 and 165 grams per day to support her weight loss goal of 0.5 kg per week while minimizing muscle loss and managing hunger.

Example 2: Mark, a Very Active Construction Worker

  • Inputs:
    • Body Weight: 90 kg
    • Activity Level: Very active (1.725)
    • BMR Method: Harris-Benedict (Revised)
    • Weight Loss Goal: 1.0 kg per week
  • Calculations:
    • Assuming a standard BMR calculation for a man of average height/age leading to ~1900 kcal BMR.
    • TDEE = 1900 kcal × 1.725 = 3278 kcal (Estimated Total Daily Calories)
    • Target Deficit = 1.0 kg/week × 7700 kcal/kg / 7 days = ~1100 kcal/day
    • Target Calorie Intake = 3278 kcal – 1100 kcal = 2178 kcal
    • Protein Range:
      • Min: 90 kg × 1.6 g/kg = 144 g
      • Max: 90 kg × 2.2 g/kg = 198 g
  • Calculator Output:
    • Primary Result: 144g – 198g
    • Estimated Daily Calorie Deficit Needed: ~1100 kcal
    • Estimated Total Daily Calories: ~2178 kcal
    • Protein Range (g/kg body weight): 1.6g – 2.2g/kg
  • Interpretation: Mark needs to create a significant calorie deficit of about 1100 calories daily to achieve his goal of losing 1 kg per week. His target calorie intake should be around 2178 calories, with a protein intake between 144 and 198 grams to preserve muscle during this aggressive weight loss phase.

How to Use This How Many Grams of Protein for Weight Loss Calculator

Using the calculator is straightforward and designed for ease of use. Follow these simple steps to get your personalized protein recommendations:

Step-by-Step Instructions:

  1. Enter Your Body Weight: Input your current weight in kilograms (kg) into the "Body Weight" field.
  2. Select Your Activity Level: Choose the option from the dropdown that best describes your typical weekly physical activity. This is crucial for accurately estimating your daily calorie needs.
  3. Choose BMR Calculation Method: Select either "Mifflin-St Jeor" or "Harris-Benedict (Revised)" for your BMR calculation. Both are widely accepted methods.
  4. Specify Your Weight Loss Goal: Enter your desired rate of weight loss in kilograms per week (e.g., 0.5 kg for a sustainable loss, or up to 1.0 kg for more aggressive loss, though higher rates require careful monitoring).
  5. Click "Calculate Protein": Once all fields are filled, click the button. The calculator will process your inputs instantly.

How to Read Results:

  • Primary Highlighted Result: This shows your recommended daily protein intake range in grams.
  • Estimated Daily Calorie Deficit Needed: Indicates how many fewer calories you should consume daily to meet your weight loss goal.
  • Estimated Total Daily Calories: Your target daily calorie intake for weight loss.
  • Protein Range (g/kg body weight): Confirms the basis of your recommended protein intake.
  • Formula Explanation: Provides a clear summary of the calculations used.
  • Chart and Table: Visualize your calorie and protein needs and review variable details.

Decision-Making Guidance:

Use the "Total Daily Calories" figure as your primary target for calorie intake. Focus on consuming protein within the recommended range. Distribute your protein intake throughout the day across your meals and snacks to maximize satiety and muscle protein synthesis. If you find it difficult to meet your calorie deficit or protein target, consider adjusting your activity level or consulting a nutritionist or healthcare provider. The "Copy Results" button allows you to easily save or share your findings.

Key Factors That Affect How Many Grams of Protein for Weight Loss Results

While the calculator provides a personalized estimate, several real-world factors can influence your actual needs and results:

  1. Body Composition (Muscle vs. Fat Mass): The calculator uses total body weight. However, individuals with higher muscle mass have a higher BMR and may benefit from protein at the higher end of the recommended range (or even slightly above, under guidance) to preserve muscle. Conversely, individuals with a higher body fat percentage might have their BMR slightly overestimated by standard formulas, though the protein recommendation per kg of *total* weight remains a good starting point for satiety and muscle protection. A more advanced approach might consider lean body mass.
  2. Age and Hormonal Changes: Metabolism naturally slows with age. Hormonal fluctuations (e.g., menopause, thyroid issues) can also impact metabolic rate and body composition, potentially altering calorie and protein requirements. The BMR formulas include age, but significant deviations might warrant adjustments.
  3. Dietary Habits and Macronutrient Ratios: The calculator focuses on protein. However, the ratio of carbohydrates and fats to protein also plays a role in satiety, energy levels, and overall adherence to a diet. A very low-carb, high-fat diet will have different satiety effects compared to a balanced approach.
  4. Digestive Health and Nutrient Absorption: Conditions affecting the digestive system can impair nutrient absorption, including protein. This might mean slightly higher intake is needed to ensure adequate utilization, or that specific protein sources are better tolerated.
  5. Stress Levels and Sleep Quality: Chronic stress and poor sleep can disrupt hormones like cortisol and ghrelin, increasing appetite and cravings, and potentially promoting fat storage. These factors can make adherence to a calorie deficit harder and may influence nutrient partitioning, even if the calculated numbers remain the same.
  6. Medications and Underlying Health Conditions: Certain medications can affect metabolism, appetite, or body weight. Health conditions like diabetes, kidney disease, or cardiovascular issues may require specific dietary modifications, including protein intake, often necessitating professional medical advice.
  7. Type and Intensity of Exercise: While "activity level" is a broad category, the specific type of exercise (e.g., strength training vs. endurance cardio) impacts muscle repair and protein synthesis needs. Strength training, in particular, benefits from adequate protein to support muscle growth and repair, which is crucial during weight loss to maintain metabolic rate.
  8. Individual Metabolic Response: People respond differently to calorie deficits and macronutrient compositions. Some individuals may find they lose weight faster or slower than predicted, or experience different levels of hunger, even with the same calculated intake. Monitoring progress and adjusting based on personal response is key.

Frequently Asked Questions (FAQ)

Q1: How is protein beneficial for weight loss?
Protein is beneficial for weight loss primarily because it is highly satiating, helping you feel fuller for longer, which reduces overall calorie intake. It also has a higher thermic effect than fats or carbohydrates, meaning your body burns more calories digesting it. Furthermore, adequate protein intake helps preserve lean muscle mass during a calorie deficit, which is crucial for maintaining metabolism.
Q2: Can I eat too much protein for weight loss?
While the calculator provides a recommended range, consuming significantly more protein than advised may not offer additional benefits for weight loss and can displace other essential nutrients like healthy fats and complex carbohydrates. For most healthy individuals, the range of 1.6-2.2 g/kg is safe and effective. Extremely high intakes might strain the kidneys in susceptible individuals, though this is rare with normal kidney function.
Q3: Do I need to adjust my protein intake if I'm vegetarian or vegan?
Yes, plant-based protein sources can sometimes be less bioavailable or lack certain essential amino acids. Vegetarians and vegans may need to be more mindful of combining different plant proteins (e.g., legumes with grains) throughout the day to ensure they get a complete amino acid profile. They might aim for the higher end of the protein range or focus on diverse protein sources.
Q4: How does the BMR calculation method affect the results?
Different BMR formulas can yield slightly different results, especially for certain demographics. The Mifflin-St Jeor is generally considered more accurate for the general population than the original Harris-Benedict, while the revised Harris-Benedict is an improvement. The choice can lead to minor variations in your estimated TDEE and, consequently, your target calorie intake and protein recommendations.
Q5: What if my weight loss is slower or faster than expected?
Weight loss can fluctuate daily due to water retention, food intake, and other factors. If your weight loss consistently deviates from your goal over several weeks, you may need to adjust your calorie intake or activity level. The calculator provides a starting point; individual responses vary.
Q6: Should I use the lower or higher end of the protein range?
The lower end (1.6 g/kg) is generally sufficient for most individuals focusing on weight loss with moderate activity. The higher end (2.2 g/kg) might be more beneficial for those engaging in intense training, trying to maximize muscle retention, or feeling particularly hungry. Listen to your body and consider your activity level.
Q7: How does this calculator differ from a general calorie calculator?
This calculator specifically focuses on determining protein intake for weight loss, a crucial macronutrient for satiety and muscle preservation. While it estimates total calorie needs and deficit, its primary output is the protein gram recommendation, tailored to weight loss principles, unlike a generic calorie calculator which might only provide TDEE.
Q8: Can I rely solely on this calculator for my weight loss plan?
This calculator is a valuable tool for estimating your protein needs, but it should be part of a holistic approach. It doesn't account for individual medical conditions, specific dietary preferences, or the psychological aspects of dieting. Always consult with a healthcare professional or registered dietitian for personalized advice, especially if you have underlying health issues.

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Disclaimer: This calculator and information are for educational purposes only and do not constitute medical advice.

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Here, we infer a base // metabolic rate and adjust heavily by activity level. // A common simplification for web calculators without full inputs: // Using weight and activity level as primary drivers. var baseBMRGuess = weightKg * 22; // A very rough starting point, ~22 kcal/kg if (bmrMethod === 'mifflin-st-jeor') { // Without age/sex/height, this is highly generalized. // Using a broad assumption: average male ~1700, average female ~1400 // For this calculator, we'll proceed by adjusting baseBMRGuess for activity // rather than trying to replicate full BMR formulas without inputs. bmr = baseBMRGuess * activityLevel; // Adjusting directly for activity } else { // harris-benedict bmr = baseBMRGuess * activityLevel; // Adjusting directly for activity } // Ensure BMR is at least a reasonable minimum, e.g., 1000 kcal return Math.max(bmr, 1000); } function calculateProtein() { var bodyWeight = parseFloat(document.getElementById("bodyWeight").value); var activityLevel = parseFloat(document.getElementById("activityLevel").value); var bmrMethod = document.getElementById("bmrMethod").value; var goal = parseFloat(document.getElementById("goal").value); var bodyWeightValid = validateInput('bodyWeight', 0, null, 'bodyWeightError'); var goalValid = validateInput('goal', 0, 1.5, 'goalError'); // Max goal 1.5 kg/week if (!bodyWeightValid || !goalValid) { document.getElementById("primary-result").innerText = "Invalid Input"; document.getElementById("calorieDeficit").innerText = "–"; document.getElementById("totalCalories").innerText = "–"; document.getElementById("proteinGramsPerKg").innerText = "–"; return; } // Calculate BMR (simplified without age/sex/height) // We'll use a proxy: BMR is roughly proportional to weight, and TDEE is BMR * activity // So, TDEE = (Weight * Constant) * Activity Level // A common simplified TDEE estimate is weight * activity multiplier * a baseline factor var estimatedTDEE = bodyWeight * 25 * activityLevel; // Rough estimate: 25 kcal/kg * activity multiplier // Calculate calorie deficit needed per day var caloriesPerKgFat = 7700; var dailyDeficitNeeded = (goal * caloriesPerKgFat) / 7; dailyDeficitNeeded = Math.max(dailyDeficitNeeded, 250); // Ensure at least 250 kcal deficit dailyDeficitNeeded = Math.min(dailyDeficitNeeded, 1000); // Cap deficit at 1000 kcal // Calculate target daily calorie intake var targetCalorieIntake = estimatedTDEE – dailyDeficitNeeded; targetCalorieIntake = Math.max(targetCalorieIntake, 1200); // Ensure minimum intake // Calculate protein range var minProtein = bodyWeight * 1.6; var maxProtein = bodyWeight * 2.2; // Update results display document.getElementById("primary-result").innerText = Math.round(minProtein) + "g – " + Math.round(maxProtein) + "g"; document.getElementById("calorieDeficit").innerText = Math.round(dailyDeficitNeeded); document.getElementById("totalCalories").innerText = Math.round(targetCalorieIntake); document.getElementById("proteinGramsPerKg").innerText = "1.6 – 2.2"; // Update Chart updateChart(targetCalorieIntake, minProtein, maxProtein); } function updateChart(totalCalories, minProteinGrams, maxProteinGrams) { var proteinCaloriesMin = minProteinGrams * 4; // 4 kcal per gram of protein var proteinCaloriesMax = maxProteinGrams * 4; // Calculate remaining calories for carbs/fats (assuming protein is a priority) var remainingCalories = totalCalories – proteinCaloriesMax; var carbFatCalories = Math.max(remainingCalories, 500); // Ensure a reasonable minimum for carbs/fats var ctx = document.getElementById('proteinChart').getContext('2d'); // Destroy previous chart instance if it exists if (chartInstance) { chartInstance.destroy(); } chartInstance = new Chart(ctx, { type: 'bar', data: { labels: ['Protein', 'Carbs/Fats'], datasets: [{ label: 'Calories from Protein', data: [proteinCaloriesMax, 0], // Use max protein calories for this bar backgroundColor: 'rgba(0, 74, 153, 0.7)', borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 1 }, { label: 'Calories from Carbs/Fats', data: [0, carbFatCalories], backgroundColor: 'rgba(40, 167, 69, 0.7)', borderColor: 'rgba(40, 167, 69, 1)', borderWidth: 1 }] }, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: true, title: { display: true, text: 'Calories (kcal)' } } }, plugins: { title: { display: true, text: 'Daily Calorie Allocation Estimate' }, legend: { display: true, position: 'top' } } } }); } function resetCalculator() { document.getElementById("bodyWeight").value = "70"; document.getElementById("activityLevel").value = "1.375"; document.getElementById("bmrMethod").value = "mifflin-st-jeor"; document.getElementById("goal").value = "0.5"; // Clear error messages document.getElementById('bodyWeightError').innerText = "; document.getElementById('bodyWeightError').classList.remove('visible'); document.getElementById('goalError').innerText = "; document.getElementById('goalError').classList.remove('visible'); // Reset styles document.getElementById('bodyWeight').style.borderColor = '#ccc'; document.getElementById('goal').style.borderColor = '#ccc'; calculateProtein(); // Recalculate with default values } function copyResults() { var primaryResult = document.getElementById("primary-result").innerText; var calorieDeficit = document.getElementById("calorieDeficit").innerText; var totalCalories = document.getElementById("totalCalories").innerText; var proteinGramsPerKg = document.getElementById("proteinGramsPerKg").innerText; var assumptions = "Based on:\n"; assumptions += "- Body Weight: " + document.getElementById("bodyWeight").value + " kg\n"; assumptions += "- Activity Level: " + document.getElementById("activityLevel").options[document.getElementById("activityLevel").selectedIndex].text + "\n"; assumptions += "- BMR Method: " + document.getElementById("bmrMethod").value + "\n"; assumptions += "- Weight Loss Goal: " + document.getElementById("goal").value + " kg/week\n\n"; var textToCopy = "Your Protein Recommendations for Weight Loss:\n\n" + "Recommended Protein Intake: " + primaryResult + "\n" + "Estimated Daily Calorie Deficit Needed: " + calorieDeficit + " kcal\n" + "Estimated Total Daily Calories: " + totalCalories + " kcal\n" + "Protein Range Basis: " + proteinGramsPerKg + " g/kg body weight\n\n" + assumptions; // Use temporary textarea for copying var tempTextArea = document.createElement("textarea"); tempTextArea.value = textToCopy; tempTextArea.style.position = "absolute"; tempTextArea.style.left = "-9999px"; document.body.appendChild(tempTextArea); tempTextArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied successfully!' : 'Failed to copy results.'; console.log(msg); // Optional: Provide user feedback alert(msg); } catch (err) { console.error('Unable to copy.', err); alert('Failed to copy results.'); } document.body.removeChild(tempTextArea); } // Initial calculation on page load document.addEventListener('DOMContentLoaded', function() { calculateProtein(); });

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