Understanding the MyFitnessPal Method
MyFitnessPal sets your initial calorie goal by first estimating your Basal Metabolic Rate (BMR), the calories your body burns at rest, using an industry-standard formula like the Mifflin-St Jeor equation. During setup, you provide information like age, gender, height, and current weight. The app then adjusts this BMR figure based on the activity level you select, and further modifies it to create a calorie deficit or surplus, depending on your weight loss or gain goals.
Unlike an explicit TDEE calculation, which accounts for all movement and the thermic effect of food, MyFitnessPal's default system creates a net calorie goal. If you log exercise, the app adds those calories back to your daily budget. This approach can be confusing for users who are used to working with a fixed TDEE number.
How to Get a More Accurate TDEE Estimate
While MyFitnessPal's automated process works for many, fitness enthusiasts and those with specific goals often prefer a more direct approach. Here’s how you can leverage the app while using a manual TDEE calculation for better precision:
- Calculate Your TDEE Externally: Use a reputable TDEE calculator online, which will first determine your BMR and then apply a more nuanced activity multiplier. Forbes Health provides a good calculator using the Mifflin-St Jeor equation.
- Choose a Realistic Deficit: Subtract a modest number of calories (e.g., 300-500) from your calculated TDEE to create a sustainable deficit for weight loss.
- Set Your MFP Goals Manually: Go into the MyFitnessPal settings and manually enter your new custom calorie goal.
- Set Activity Level to 'Sedentary': Critically, when using your own TDEE, you should set your activity level in MyFitnessPal to the lowest possible setting. This prevents the app from double-counting your calories burned. When you exercise, you can log it, but many experienced users recommend not eating back all your exercise calories, as app estimates can be generous.
Potential Inaccuracies and Best Practices
MyFitnessPal’s accuracy depends heavily on the quality of user-entered data. Calorie counts from user-submitted foods can be inaccurate, and portion sizes must be meticulously tracked for the numbers to hold up.
Here are some best practices for maximizing accuracy:
- Use a Food Scale: Don't rely on visual portion size estimates. A digital kitchen scale provides the most precise measurements for your food intake.
- Verify Food Entries: Double-check the nutrition information, especially for packaged foods, against the label. Barcode scanning can be reliable, but user-submitted entries can vary wildly.
- Monitor Trends, Not Daily Fluctuations: TDEE calculators and apps are best for tracking trends over weeks, not day-to-day. Your weight and calorie expenditure naturally fluctuate, so focus on the long-term averages.
MyFitnessPal vs. Manual TDEE Calculation: A Comparison
| Feature | MyFitnessPal (Default) | Manual TDEE Calculation |
|---|---|---|
| Method | Estimates BMR, adjusts for activity and weight goal, then adds back exercise calories. | Estimates BMR (e.g., Mifflin-St Jeor), multiplies by an activity factor (e.g., 1.55), then sets a custom calorie target. |
| Primary Metric | Net Calorie Goal (Food calories - Exercise calories) | Gross TDEE (Maintenance calories) |
| Accuracy | Good for general guidance, but relies on user-provided activity levels and exercise logging, which can be imprecise. | Can be more accurate if the user correctly assesses their activity level and consistently tracks intake. |
| Customization | Basic adjustments based on weight goals and activity. Premium offers more control over macro percentages. | Complete control over your calorie goal and deficit. Requires more external research and initial effort. |
| Exercise Logging | Automatically adds calories back to your daily budget. | Not necessary to log exercise for calorie credit, as your custom goal already accounts for your activity. |
Conclusion: Can MyFitnessPal calculate TDEE?
MyFitnessPal does not explicitly calculate and display a TDEE number. Instead, it uses a simplified, automated process based on your BMR, activity level, and weight goals to generate a net calorie target. While this system works effectively for many users, those who prefer more precision or want to work with a fixed TDEE figure can do so by manually calculating their own TDEE and inputting a custom calorie goal into the app. For the most accurate results, regardless of the method, consistent food tracking and careful portion measurement are crucial. Ultimately, the best approach depends on your personal preference and how hands-on you want to be with your calorie tracking.
