Calculating Protein for Weight Loss

Calculate Your Ideal Protein Intake for Weight Loss | Protein Calculator body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f8f9fa; color: #333; line-height: 1.6; margin: 0; padding: 0; } .container { max-width: 960px; margin: 20px auto; padding: 20px; background-color: #ffffff; border-radius: 8px; box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1); display: flex; flex-direction: column; } h1, h2, h3 { color: #004a99; text-align: center; margin-bottom: 1.5em; } .calculator-section { margin-bottom: 30px; padding: 20px; border: 1px solid #dee2e6; border-radius: 6px; background-color: #e9ecef; } .input-group { margin-bottom: 15px; display: flex; flex-direction: column; } .input-group label { font-weight: bold; margin-bottom: 5px; color: #004a99; } .input-group input, .input-group select { padding: 10px; border: 1px solid #ced4da; border-radius: 4px; font-size: 1rem; box-sizing: border-box; /* Ensure padding doesn't affect width */ } .input-group input:focus, .input-group select:focus { border-color: #004a99; outline: none; box-shadow: 0 0 0 3px rgba(0, 74, 153, 0.25); } .helper-text { font-size: 0.85em; color: #6c757d; margin-top: 5px; } .error-message { color: #dc3545; font-size: 0.8em; margin-top: 5px; display: none; /* Hidden by default */ } .error-message.visible { display: block; } .button-group { display: flex; justify-content: space-between; margin-top: 20px; flex-wrap: wrap; gap: 10px; } button { padding: 12px 25px; border: none; border-radius: 5px; cursor: pointer; font-size: 1rem; font-weight: bold; transition: background-color 0.3s ease; color: white; } .btn-primary { background-color: #004a99; } .btn-primary:hover { background-color: #003b7d; } .btn-secondary { background-color: #6c757d; } .btn-secondary:hover { background-color: #5a6268; } .btn-success { background-color: #28a745; } .btn-success:hover { background-color: #218838; } #results { margin-top: 30px; padding: 25px; border: 1px solid #28a745; border-radius: 6px; background-color: #d4edda; color: #155724; display: flex; flex-direction: column; align-items: center; } #results h3 { margin-top: 0; color: #155724; margin-bottom: 1em; } .primary-result { font-size: 2.5em; font-weight: bold; color: #004a99; margin: 10px 0; background-color: #ffffff; padding: 15px 30px; border-radius: 5px; box-shadow: 0 4px 8px rgba(0, 74, 153, 0.2); } .intermediate-results { margin-top: 20px; font-size: 1.1em; text-align: center; } .intermediate-results span { font-weight: bold; color: #004a99; } .formula-explanation { font-size: 0.9em; color: #444; margin-top: 15px; text-align: center; border-top: 1px dashed #ccc; padding-top: 15px; } table { width: 100%; border-collapse: collapse; margin-top: 20px; } th, td { padding: 10px; text-align: left; border-bottom: 1px solid #dee2e6; } th { background-color: #004a99; color: white; } tbody tr:nth-child(odd) { background-color: #f2f2f2; } caption { font-size: 1.1em; font-weight: bold; color: #004a99; margin-bottom: 10px; text-align: left; } #chartContainer { width: 100%; margin-top: 20px; background-color: #fff; padding: 15px; border-radius: 6px; box-shadow: 0 2px 5px rgba(0,0,0,0.1); } #chartContainer canvas { display: block; /* Remove extra space below canvas */ } .article-content { margin-top: 40px; padding: 20px; background-color: #ffffff; border-radius: 8px; box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1); } .article-content h2, .article-content h3 { text-align: left; margin-bottom: 1em; } .article-content p { margin-bottom: 1.2em; } .article-content ul, .article-content ol { margin-bottom: 1.2em; padding-left: 25px; } .article-content li { margin-bottom: 0.8em; } .article-content a { color: #004a99; text-decoration: none; } .article-content a:hover { text-decoration: underline; } .faq-item { margin-bottom: 1.5em; } .faq-item h4 { margin-bottom: 0.5em; color: #004a99; font-size: 1.1em; } .faq-item p { margin-bottom: 0; } .internal-links ul { list-style: none; padding: 0; } .internal-links li { margin-bottom: 1em; } .internal-links a { font-weight: bold; } .internal-links p { font-size: 0.9em; color: #555; margin-top: 0.3em; } /* Responsive adjustments */ @media (max-width: 768px) { .container { margin: 10px; padding: 15px; } button { width: 100%; margin-bottom: 10px; } .button-group { flex-direction: column; align-items: center; } }

Protein Calculator for Weight Loss

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

Calculate Your Protein Needs

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)
Select your typical weekly physical activity.
Enter your current body weight in kilograms.
Enter your height in centimeters.
Enter your age.
Male Female
Select your gender.
How quickly do you aim to lose weight (e.g., 0.5 kg per week)?

Your Protein Recommendations

— g

Lean Body Mass (LBM): — kg

Basal Metabolic Rate (BMR): — kcal

Total Daily Energy Expenditure (TDEE): — kcal

Protein intake is calculated as a percentage of lean body mass, adjusted for weight loss goals. Higher protein aids satiety and muscle preservation.

Protein Intake Breakdown

Estimated Daily Protein Intake Based on Weight Loss Goal
Weight Loss Goal (kg/week) Recommended Protein (g/day) Protein as % of LBM

Protein Intake vs. TDEE

What is Calculating Protein for Weight Loss?

Calculating protein for weight loss is a process designed to determine the optimal daily protein intake for an individual seeking to reduce body weight effectively and sustainably. It goes beyond simply guessing and uses physiological data and weight loss goals to provide a personalized target. This approach acknowledges that protein plays a crucial role in satiety, muscle preservation during calorie deficit, and metabolic rate, all of which are critical for successful weight management.

Who should use it? Anyone embarking on a weight loss journey, from beginners to those who have struggled with previous attempts, can benefit from understanding their specific protein needs. Athletes looking to shed body fat while maintaining muscle mass, individuals aiming for better appetite control, or those simply wanting a structured approach to their diet can find value in this calculation. It's particularly useful for those who are active or aiming for a significant calorie deficit where muscle loss can become a concern.

Common misconceptions about protein for weight loss include the idea that "more is always better," which can lead to excessive calorie intake or digestive strain. Another misconception is that high protein diets are solely for bodybuilders; in reality, they are highly beneficial for general weight loss due to their satiating effects. Some also believe that protein needs are static, not considering factors like activity level, age, or the rate of weight loss desired, all of which influence optimal intake. Understanding the nuances of calculating protein for weight loss helps debunk these myths.

Protein Intake Formula and Mathematical Explanation

The calculation of protein for weight loss typically involves several steps, combining established formulas for Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) with specific protein recommendations based on lean body mass and weight loss goals.

Step 1: Calculate Basal Metabolic Rate (BMR). We use the Mifflin-St Jeor equation, which is considered one of the most accurate:
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

Step 2: Estimate Lean Body Mass (LBM). A common estimation uses body fat percentage. If body fat percentage isn't known, we can use an approximation based on gender and age, or a simplified approach assuming a certain body fat percentage. A simpler, often used method for weight loss calculators is to directly use a portion of the target body weight or current weight as a proxy, but for better accuracy, we'll estimate LBM. For simplicity in this calculator, we estimate LBM using a standard body fat percentage:
Approximate Body Fat Percentage:
– Male: ~20%
– Female: ~30%
LBM = Total Weight * (1 – Body Fat Percentage)

Step 3: Calculate Total Daily Energy Expenditure (TDEE). This is BMR multiplied by an activity factor:
TDEE = BMR × Activity Factor
Activity Factors:
– Sedentary: 1.2
– Lightly Active: 1.375
– Moderately Active: 1.55
– Very Active: 1.725
– Extra Active: 1.9

Step 4: Determine Protein Intake. For weight loss, protein intake is often recommended as a higher percentage of lean body mass to promote satiety and muscle retention. A common range is 1.6 to 2.2 grams of protein per kilogram of Lean Body Mass (LBM), potentially adjusted slightly by the weight loss goal. A deficit of 500-1000 kcal/day typically leads to 0.5-1 kg loss per week. We will aim for a protein intake that supports a moderate deficit while maximizing protein's benefits.
Protein Target (g/day) = LBM (kg) × Protein Multiplier (g/kg LBM)
The multiplier varies based on goals:
– Maintaining muscle with modest deficit: ~1.6 – 1.8 g/kg LBM
– Aggressive fat loss & muscle preservation: ~1.8 – 2.2 g/kg LBM
To simplify and provide a actionable range, we'll use a base multiplier and adjust based on the desired weight loss rate, ensuring it remains within healthy bounds. For significant weight loss goals (e.g., >1kg/week), we cap the multiplier to prevent excessive protein intake.

Variables Table:

Variable Meaning Unit Typical Range
Weight Current body weight kg 30 – 200
Height Body height cm 50 – 250
Age Individual's age Years 5 – 120
Gender Biological sex N/A Male / Female
Activity Level Frequency and intensity of exercise N/A Sedentary to Extra Active
Weight Loss Rate Target weekly weight loss kg/week 0.1 – 2.0
BMR Calories burned at rest kcal/day Varies (e.g., 1200-2000+)
LBM Weight excluding fat mass kg Varies (e.g., 40-100+)
TDEE Total daily calories burned kcal/day Varies (e.g., 1800-3500+)
Protein Intake Recommended daily protein consumption grams/day Varies (e.g., 80-200+)

Practical Examples (Real-World Use Cases)

Let's illustrate how calculating protein for weight loss works with two distinct scenarios:

Example 1: Sarah, a Moderately Active Office Worker

Inputs:

  • Gender: Female
  • Age: 35
  • Weight: 70 kg
  • Height: 165 cm
  • Activity Level: Moderately Active
  • Desired Weight Loss Rate: 0.5 kg/week
Calculation Process:
  1. BMR: (10 * 70) + (6.25 * 165) – (5 * 35) – 161 = 700 + 1031.25 – 175 – 161 = 1395.25 kcal
  2. LBM (Est. 30% BF): 70 kg * (1 – 0.30) = 49 kg
  3. TDEE: 1395.25 kcal * 1.55 (Moderately Active) = 2163 kcal
  4. Protein Target: LBM * (1.8 g/kg) = 49 kg * 1.8 = 88.2 g/day. (Slightly higher multiplier for weight loss goal).
Results:
  • Estimated LBM: 49 kg
  • Estimated BMR: 1395 kcal
  • Estimated TDEE: 2163 kcal
  • Recommended Daily Protein: ~88 grams
Interpretation: Sarah needs approximately 88 grams of protein daily. This intake, combined with a moderate calorie deficit (around 500-600 kcal below TDEE), should support her goal of losing about 0.5 kg per week while preserving muscle mass and helping her feel full between meals.

Example 2: Mark, a Very Active Young Professional

Inputs:

  • Gender: Male
  • Age: 28
  • Weight: 85 kg
  • Height: 180 cm
  • Activity Level: Very Active
  • Desired Weight Loss Rate: 1.0 kg/week
Calculation Process:
  1. BMR: (10 * 85) + (6.25 * 180) – (5 * 28) + 5 = 850 + 1125 – 140 + 5 = 1840 kcal
  2. LBM (Est. 20% BF): 85 kg * (1 – 0.20) = 68 kg
  3. TDEE: 1840 kcal * 1.725 (Very Active) = 3171 kcal
  4. Protein Target: LBM * (2.0 g/kg) = 68 kg * 2.0 = 136 g/day. (Higher multiplier for aggressive weight loss goal).
Results:
  • Estimated LBM: 68 kg
  • Estimated BMR: 1840 kcal
  • Estimated TDEE: 3171 kcal
  • Recommended Daily Protein: ~136 grams
Interpretation: Mark, aiming for a faster weight loss of 1 kg per week, requires a higher protein intake of around 136 grams. This higher intake is crucial for preserving the muscle mass he builds through intense training while undergoing a significant calorie deficit (around 1000 kcal below TDEE).

How to Use This Protein Calculator for Weight Loss

Our calculator is designed for simplicity and accuracy. Follow these steps to get your personalized protein recommendations:

  1. Enter Your Details: Accurately input your current weight (kg), height (cm), age, and gender.
  2. Select Activity Level: Choose the option that best describes your typical weekly exercise routine. Be honest to get the most accurate results.
  3. Specify Weight Loss Goal: Indicate your desired weekly weight loss rate in kilograms per week. A safe and sustainable rate is typically between 0.5 kg and 1.0 kg per week.
  4. Click 'Calculate Protein': The calculator will instantly process your inputs.

How to Read Results:

  • Primary Result (Recommended Daily Protein): This is your target protein intake in grams per day.
  • Lean Body Mass (LBM): This is an estimation of your weight excluding body fat. Protein recommendations are often based on LBM for better accuracy.
  • Basal Metabolic Rate (BMR): The calories your body burns at complete rest.
  • Total Daily Energy Expenditure (TDEE): The total estimated calories you burn per day, including activity. Your calorie deficit for weight loss will be based on this number.
  • Protein Breakdown Table: Shows how your recommended protein intake aligns with different weight loss rates, providing context.
  • Chart: Visualizes your TDEE relative to potential protein intake levels.

Decision-making Guidance: Use the recommended protein intake as a target for your daily meals. Aim to distribute protein intake throughout the day. Remember that this is a guideline; listen to your body. If you experience discomfort or have specific health conditions, consult a healthcare professional or registered dietitian. For sustainable weight loss, pair this protein target with a balanced diet and adequate hydration. Exploring resources on healthy meal planning can further support your journey.

Key Factors That Affect Protein Recommendations

While the calculator provides a solid estimate, several factors can influence your ideal protein intake for weight loss:

  • Muscle Mass and Training Intensity: Individuals with higher muscle mass or engaging in intense strength training often require more protein to support muscle repair and growth, even during a calorie deficit. Our calculator estimates LBM, but precise body composition analysis could refine this.
  • Age: As we age, protein synthesis efficiency can decrease. Older adults may benefit from a slightly higher protein intake to combat sarcopenia (age-related muscle loss), even if their weight loss goal is moderate.
  • Rate of Weight Loss: Aggressively cutting calories while aiming for rapid weight loss increases the risk of muscle loss. A higher protein intake becomes even more critical in such scenarios to preserve lean tissue.
  • Dietary Preferences and Restrictions: Vegetarian or vegan individuals may need careful planning to meet protein goals, potentially using a wider variety of plant-based sources or supplements. The calculator assumes general dietary access.
  • Underlying Health Conditions: Certain conditions, like kidney disease, may require modifications to protein intake. Always consult a doctor if you have pre-existing health concerns. This calculator is not a substitute for medical advice.
  • Hormonal Factors: Hormonal fluctuations (e.g., related to menstrual cycles, thyroid issues, or menopause) can impact metabolism and appetite, potentially influencing how well one tolerates or utilizes protein.
  • Thermic Effect of Food (TEF): Protein has a higher TEF than carbohydrates or fats, meaning your body burns more calories digesting it. While not directly factored into the grams/day calculation, it contributes to the overall metabolic advantage of higher protein diets during weight loss.

Frequently Asked Questions (FAQ)

Q1: How much protein is too much during weight loss?

While high protein is beneficial, excessively high intake (e.g., > 2.5g per kg of LBM) may not offer additional benefits for weight loss and could strain the kidneys in susceptible individuals. It can also lead to consuming more calories than intended. Stick to recommended ranges.

Q2: Does calculating protein for weight loss account for meal timing?

This calculator focuses on the total daily intake. While spreading protein throughout the day (e.g., 20-40g per meal) can help with satiety and muscle protein synthesis, the total daily amount is the primary driver for weight loss and muscle preservation.

Q3: Can I use this calculator if I'm trying to gain muscle instead of losing weight?

This calculator is specifically optimized for weight loss. Muscle gain requires a calorie surplus and different macronutrient ratios. We have other tools that might be more suitable for muscle gain calculations.

Q4: Should I adjust protein intake based on my specific diet (e.g., keto, paleo)?

While this calculator provides a general guideline, specific diets might have their own recommendations. For instance, ketogenic diets are naturally higher in fat, and protein intake is often kept moderate to high, similar to these recommendations. Always ensure your diet aligns with your overall health goals and consult a professional if needed.

Q5: What if my weight fluctuates daily?

Use your average weight over the past week or your most consistent weigh-in weight for the calculator. Daily fluctuations are normal due to water retention and other factors; focus on the overall trend.

Q6: How does calculating protein for weight loss differ from calculating general protein needs?

General protein needs are typically lower (e.g., 0.8-1.2 g/kg body weight) for sedentary individuals or those not actively trying to lose weight. During weight loss, a higher protein intake (e.g., 1.6-2.2 g/kg LBM) is recommended to maximize satiety, preserve muscle mass, and support metabolism during a calorie deficit.

Q7: Is it safe to eat over 150g of protein per day?

For most healthy adults, consuming up to 2.2g of protein per kg of Lean Body Mass is considered safe and effective for weight loss goals. For individuals with specific health conditions, like kidney issues, lower intakes may be necessary. Always consult a healthcare provider for personalized advice.

Q8: How can I easily increase my protein intake?

Incorporate protein sources into every meal and snack. Good options include lean meats, poultry, fish, eggs, dairy products (like Greek yogurt and cottage cheese), legumes, tofu, tempeh, and protein powders.

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Min: " + min + ", Max: " + max; errorElement.classList.add('visible'); return false; } else { errorElement.textContent = ""; errorElement.classList.remove('visible'); return true; } } function calculateProtein() { var weightKg = parseFloat(document.getElementById("weightKg").value); var heightCm = parseFloat(document.getElementById("heightCm").value); var age = parseFloat(document.getElementById("age").value); var gender = document.getElementById("gender").value; var activityLevel = document.getElementById("activityLevel").value; var weightLossGoalKgPerWeek = parseFloat(document.getElementById("weightLossGoalKgPerWeek").value); var inputsValid = true; inputsValid = validateInput('weightKg', 1, 200) && inputsValid; inputsValid = validateInput('heightCm', 50, 250) && inputsValid; inputsValid = validateInput('age', 5, 120) && inputsValid; inputsValid = validateInput('weightLossGoalKgPerWeek', 0.1, 2.0) && inputsValid; if (!inputsValid) { // Clear results if inputs are invalid document.getElementById("primaryResult").textContent = "– g"; document.getElementById("leanBodyMass").textContent = "– kg"; document.getElementById("bmr").textContent = "– kcal"; document.getElementById("tdee").textContent = "– kcal"; document.getElementById("proteinTableBody").innerHTML = ""; return; } // Calculate BMR (Mifflin-St Jeor Equation) var bmr = 0; if (gender === "male") { bmr = (10 * weightKg) + (6.25 * heightCm) – (5 * age) + 5; } else { // female bmr = (10 * weightKg) + (6.25 * heightCm) – (5 * age) – 161; } bmr = Math.round(bmr); // Estimate Lean Body Mass (LBM) – simplified approach var bodyFatPercentage = 0.20; // Default for male if (gender === "female") { bodyFatPercentage = 0.30; // Default for female } // Adjust body fat percentage slightly based on age (optional, for more refinement) // E.g., add 1% per decade over 30 for males, over 40 for females var leanBodyMass = weightKg * (1 – bodyFatPercentage); leanBodyMass = Math.round(leanBodyMass * 10) / 10; // Round to one decimal place // Calculate TDEE using Activity Factor var activityFactor = 1.2; // Sedentary if (activityLevel === "lightly_active") { activityFactor = 1.375; } else if (activityLevel === "moderately_active") { activityFactor = 1.55; } else if (activityLevel === "very_active") { activityFactor = 1.725; } else if (activityLevel === "extra_active") { activityFactor = 1.9; } var tdee = bmr * activityFactor; tdee = Math.round(tdee); // Determine Protein Multiplier based on weight loss goal var proteinMultiplierPerKgLBM = 1.6; // Base for moderate deficit if (weightLossGoalKgPerWeek >= 0.7) { // More aggressive goal proteinMultiplierPerKgLBM = 1.8; } if (weightLossGoalKgPerWeek >= 1.0) { // Very aggressive goal proteinMultiplierPerKgLBM = 2.0; } if (weightLossGoalKgPerWeek >= 1.5) { // Extreme goal, cap to prevent excessive intake proteinMultiplierPerKgLBM = 2.2; } // Ensure multiplier doesn't exceed a reasonable upper limit proteinMultiplierPerKgLBM = Math.min(proteinMultiplierPerKgLBM, 2.2); var proteinGrams = leanBodyMass * proteinMultiplierPerKgLBM; proteinGrams = Math.round(proteinGrams); // Update Results Display document.getElementById("primaryResult").textContent = proteinGrams + " g"; document.getElementById("leanBodyMass").textContent = leanBodyMass + " kg"; document.getElementById("bmr").textContent = bmr + " kcal"; document.getElementById("tdee").textContent = tdee + " kcal"; // Populate Protein Breakdown Table and update chart data populateProteinTable(leanBodyMass, weightLossGoalKgPerWeek); updateChart(tdee, proteinGrams, proteinMultiplierPerKgLBM); } function populateProteinTable(lbm, currentGoal) { var tableBody = document.getElementById("proteinTableBody"); tableBody.innerHTML = ""; // Clear previous rows var goals = [0.25, 0.5, 0.75, 1.0, 1.25, 1.5]; // Different weight loss goals in kg/week var proteinMultipliers = {}; // Define multipliers for different goals goals.forEach(function(goal) { var multiplier = 1.6; // Base if (goal >= 0.7) multiplier = 1.8; if (goal >= 1.0) multiplier = 2.0; if (goal >= 1.5) multiplier = 2.2; multiplier = Math.min(multiplier, 2.2); // Cap proteinMultipliers[goal] = multiplier; }); goals.forEach(function(goal) { var multiplier = proteinMultipliers[goal]; var recommendedProtein = Math.round(lbm * multiplier); var proteinPercentOfLBM = multiplier; // Stored as g/kg LBM var row = tableBody.insertRow(); var cell1 = row.insertCell(0); var cell2 = row.insertCell(1); var cell3 = row.insertCell(2); cell1.textContent = goal.toFixed(2) + " kg/week"; cell2.textContent = recommendedProtein + " g"; cell3.textContent = proteinPercentOfLBM.toFixed(1) + " g/kg LBM"; // Highlight the row corresponding to the current goal if it exists if (Math.abs(goal – currentGoal) < 0.05) { // Check if current goal is close to this row's goal row.style.backgroundColor = "#d0e9c6"; // Light green highlight row.style.fontWeight = "bold"; } }); } function updateChart(tdee, proteinGrams, proteinMultiplier) { var ctx = document.getElementById('proteinTdeeChart').getContext('2d'); // Define a range of protein intakes to plot against TDEE var proteinIntakeRange = [ Math.round(parseFloat(document.getElementById("leanBodyMass").textContent) * 1.6), // Lower end Math.round(parseFloat(document.getElementById("leanBodyMass").textContent) * 2.2) // Higher end ]; 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textArea.value = textToCopy; textArea.style.position = "fixed"; textArea.style.left = "-9999px"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied successfully!' : 'Failed to copy results.'; alert(msg); // Simple feedback } catch (err) { alert('Oops, unable to copy. Please copy manually.'); } document.body.removeChild(textArea); } function resetForm() { document.getElementById("weightKg").value = "70"; document.getElementById("heightCm").value = "170"; document.getElementById("age").value = "30"; document.getElementById("gender").value = "female"; document.getElementById("activityLevel").value = "moderately_active"; document.getElementById("weightLossGoalKgPerWeek").value = "0.5"; // Clear errors var errorElements = document.querySelectorAll('.error-message'); for (var i = 0; i < errorElements.length; i++) { errorElements[i].textContent = ""; errorElements[i].classList.remove('visible'); } calculateProtein(); // Recalculate with default values } // Initial calculation on page load document.addEventListener('DOMContentLoaded', function() { calculateProtein(); // Ensure chart is initialized correctly on load if canvas is ready var canvas = document.getElementById('proteinTdeeChart'); if(canvas) { var ctx = canvas.getContext('2d'); // Placeholder init to prevent errors if data isn't ready window.myChart = new Chart(ctx, { type: 'line', data: { datasets: [] }, options: {} }); window.myChart.destroy(); // Destroy placeholder } calculateProtein(); // Trigger calculation and chart update });

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