How Many Calories Should I Eat? The Ultimate Guide to TDEE and Weight Loss

If you want to change your body weight, there is one fundamental law of physics you cannot escape: Energy Balance. To lose weight, you must burn more energy than you consume. To gain weight, you must consume more than you burn.

But how do you know how much you burn? You aren't a car with a fuel gauge. Your body is a complex biological machine that burns different amounts of fuel every day based on movement, digestion, and even thinking. This 'daily burn' number is called your **TDEE**.

In this guide, we will demystify TDEE, explain how to calculate it accurately, and show you exactly how many calories you should eat to reach your goals.

What is TDEE (Total Daily Energy Expenditure)?

Your TDEE is not just one number. It is the sum of four distinct calorie-burning processes that happen in your body every day:

1. BMR (Basal Metabolic Rate) - ~70% of TDEE

This is the energy your body needs just to stay alive. If you laid in bed all day in a coma, you would still burn these calories keeping your heart beating, lungs breathing, and brain functioning. This makes up the majority of your daily burn.

2. NEAT (Non-Exercise Activity Thermogenesis) - ~15% of TDEE

This is all the movement you do that *isn't* deliberate exercise. Walking to the car, fidgeting at your desk, cooking dinner, doing laundry. People with active jobs (like nurses or construction workers) have massive NEAT levels compared to office workers.

3. TEF (Thermic Effect of Food) - ~10% of TDEE

Digesting food takes energy. Interestingly, different foods burn different amounts. Protein has the highest TEF (your body burns about 20-30% of protein calories just digesting them!), while fat has the lowest (0-3%).

4. EAT (Exercise Activity Thermogenesis) - ~5% of TDEE

This is your gym session, your run, or your yoga class. Surprisingly, structured exercise often burns fewer calories than people think compared to BMR and NEAT.

How to Calculate Your TDEE

Since we can't measure your metabolism in a lab, we use mathematical formulas to estimate it based on averages. The most accurate and widely used formula today is the **Mifflin-St Jeor Equation**.

It calculates your BMR first, then applies an 'Activity Multiplier' (from 1.2 for sedentary to 1.9 for athletes) to find your TDEE.

Creating a Calorie Deficit: Safe Weight Loss

Once you know your TDEE (Maintenance), you simply subtract calories to lose weight. But how much should you subtract?

• •**Conservative (-250 kcal/day)**: Loss of ~0.5 lbs/week. Best for people who differ from their goal weight by less than 10-15 lbs, or who want to maximize gym performance.
• •**Moderate (-500 kcal/day)**: Loss of ~1 lb/week. The standard recommendation. Sustainable for most people.
• •**Aggressive (-1000 kcal/day)**: Loss of ~2 lbs/week. Difficult to sustain and risks muscle loss. Usually only recommended for those with higher starting body fat percentages.

Why Weight Loss Plateaus (Metabolic Adaptation)

Many people find they lose weight for a few weeks, then stop, even though they are eating the same amount. Why? Because **your TDEE changes as you shrink**.

A smaller body requires less energy to move and exist. If you lose 20 lbs, your BMR drops. Your TDEE drops. The 2000 calories that used to be a deficit might now be your maintenance level. To continue losing weight, you must recalculate your TDEE and adjust your intake.

The Role of Macros

While calories determine *weight* change, macronutrients determine *body composition* change (muscle vs. fat).

1. 1**Protein**: Essential for muscle repair and satiety. High protein diets help you hold onto muscle while losing fat.
2. 2**Carbohydrates**: The body's preferred fuel source for high-intensity exercise.
3. 3**Fats**: Crucial for hormone regulation and nutrient absorption.

A common split for weight loss is 40% Protein, 30% Fat, 30% Carbs, but personal preference matters most. The best diet is the one you can stick to.

Conclusion

Weight loss is simple math, but complex psychology. Your TDEE gives you the roadmap, but consistency is the vehicle. Start by tracking your intake for a week without changing anything to see your baseline, then apply a moderate deficit.

Ready to get your number? Use our free calculator below.