1. What is TDEE?

TDEE (Total Daily Energy Expenditure) represents the number of calories you burn in a day, including basal metabolic rate (BMR) and physical activity. It's commonly referred to as "maintenance calories" - the amount needed to maintain your current weight.

2. How Does the Calculator Work?

The calculator uses the Mifflin-St Jeor Equation for BMR:

Where \( s \) is +5 for men and -161 for women.

TDEE is then calculated by multiplying BMR by an activity factor:

• 1.2 — Sedentary (little or no exercise)
• 1.375 — Lightly active (light exercise 1-3 days/week)
• 1.55 — Moderately active (moderate exercise 3-5 days/week)
• 1.725 — Very active (hard exercise 6-7 days/week)
• 1.9 — Extra active (very hard exercise & physical job)

3. Importance of Maintenance Calories

Details: Knowing your TDEE helps with weight management - consuming more leads to weight gain, consuming less leads to weight loss. NHS recommends gradual changes of ±500 kcal/day for safe weight management.

4. Using the Calculator

Tips: For accurate results, measure weight in kg and height in cm. Be honest about your activity level - most people overestimate their activity.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculator?
A: It provides a good estimate for most people, but individual variations exist due to muscle mass, genetics, and other factors.

Q2: Should I eat exactly my TDEE to maintain weight?
A: Use it as a starting point. Monitor your weight over 2-4 weeks and adjust as needed.

Q3: How often should I recalculate my TDEE?
A: Recalculate after significant weight changes (±5kg) or activity level changes.

Q4: Why does TDEE decrease with age?
A: Metabolism naturally slows with age due to decreased muscle mass and hormonal changes.

Q5: Can I use this for weight loss?
A: Yes, subtract 500 kcal/day for gradual weight loss (~0.5kg/week) as recommended by NHS.