The Ultimate Guide to Energy Needs: How to Calculate EER, BMR, and TER

Introduction

Energy requirements vary from person to person, depending on age, sex, body composition, and activity level. Understanding how to calculate Basal Metabolic Rate (BMR), Estimated Energy Requirement (EER), and Total Energy Requirement (TER) is essential for students, fresh graduates, and practising nutritionists.

This guide provides a step-by-step approach to calculating energy needs and practical examples to help you apply these concepts in clinical and public health nutrition.

1. Understanding BMR: Your Body’s Energy Baseline

Basal Metabolic Rate (BMR) refers to the minimum number of calories required to keep the body functioning at rest. This includes breathing, circulation, and cell production.

How to Calculate BMR

Two widely used equations for calculating BMR are:

✅ Harris-Benedict Equation (Most Common)

🔹 For Men:

BMR=88.36+(13.4×weight(kg))+(4.8×height(cm))−(5.7×age(years))BMR = 88.36 + (13.4 × weight \text{(kg)}) + (4.8 × height \text{(cm)}) - (5.7 × age \text{(years)})

🔹 For Women:

BMR=447.6+(9.2×weight(kg))+(3.1×height(cm))−(4.3×age(years))BMR = 447.6 + (9.2 × weight \text{(kg)}) + (3.1 × height \text{(cm)}) - (4.3 × age \text{(years)})

✅ Mifflin-St Jeor Equation (More Accurate)

🔹 For Men:

BMR=(10×weight(kg))+(6.25×height(cm))−(5×age(years))+5BMR = (10 × weight \text{(kg)}) + (6.25 × height \text{(cm)}) - (5 × age \text{(years)}) + 5

🔹 For Women:

BMR=(10×weight(kg))+(6.25×height(cm))−(5×age(years))−161BMR = (10 × weight \text{(kg)}) + (6.25 × height \text{(cm)}) - (5 × age \text{(years)}) - 161

Example Calculation

👩 Jane, a 25-year-old female, weighing 65 kg and 165 cm tall

Using the Mifflin-St Jeor equation:

BMR=(10×65)+(6.25×165)−(5×25)−161BMR = (10 × 65) + (6.25 × 165) - (5 × 25) - 161 =650+1031.25−125−161= 650 + 1031.25 - 125 - 161 =1395.25 kcal/day= 1395.25 \text{ kcal/day}

Jane needs ~1395 kcal/day just to sustain basic functions.

2. Estimating Energy Needs: Total Energy Requirement (TER)

Once BMR is calculated, we multiply it by an Activity Factor to determine Total Energy Requirement (TER):

Activity Factors

Example Calculation for Jane

Jane exercises 3–4 days a week, so she is Moderately Active (Factor = 1.55).

TER=BMR×ActivityFactorTER = BMR × Activity Factor TER=1395×1.55=2162.25 kcal/dayTER = 1395 × 1.55 = 2162.25 \text{ kcal/day}

So, Jane needs ~2162 kcal/day to maintain her weight with her activity level.

3. Estimating Energy Requirement (EER) for Weight Goals

EER determines the energy needed to gain, lose, or maintain weight.

🔹 For Weight Maintenance → Use TER
🔹 For Weight Loss → Subtract 500 kcal/day for ~0.5kg/week loss
🔹 For Weight Gain → Add 500 kcal/day for ~0.5kg/week gain

Example: Jane Wants to Lose Weight

EER=2162−500=1662 kcal/dayEER = 2162 - 500 = 1662 \text{ kcal/day}

Jane should consume ~1662 kcal/day to lose ~0.5 kg per week.

4. Practical Applications for Dietitians & Nutritionists

📌 For Clinical Dietetics

• Calculate EER for diabetic patients to balance blood sugar
• Adjust EER for underweight/malnourished patients

📌 For Public Health & Community Nutrition

• Develop meal plans for schools & corporate wellness programs
• Design nutrition interventions based on population needs

📌 For Weight Management & Sports Nutrition

• Calculate TER for athletes and active individuals
• Plan diets based on muscle-building or fat-loss goals

5. Free EER & BMR Calculation Template (Downloadable)

💡 To make your calculations easier, download our free energy requirement calculator template [here] (Link to resource).

Conclusion

Mastering BMR, EER, and TER calculations is a foundational skill for every nutritionist and dietitian. Whether you're preparing for internships, job interviews, or real-world practice, understanding energy balance will set you apart.