Harris Benedict Formula Calculator

Harris Benedict Formula:

\[ BMR = 655 + (9.6 \times Weight) + (1.8 \times Height) - (4.7 \times Age) \text{ (female)} \] \[ BMR = 66 + (13.7 \times Weight) + (5 \times Height) - (6.8 \times Age) \text{ (male)} \]

Weight:

Height:

Age:

years

Gender:

Basal Metabolic Rate (BMR):

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1. What is the Harris Benedict Formula?

The Harris-Benedict equation estimates basal metabolic rate (BMR), which is the number of calories your body needs at complete rest. It was first published in 1919 and revised in 1984 to improve accuracy.

2. How Does the Calculator Work?

The calculator uses the Harris-Benedict equations:

\[ \text{Female: } BMR = 655 + (9.6 \times Weight) + (1.8 \times Height) - (4.7 \times Age) \] \[ \text{Male: } BMR = 66 + (13.7 \times Weight) + (5 \times Height) - (6.8 \times Age) \]

Where:

\( Weight \) — Body weight in kilograms
\( Height \) — Height in centimeters
\( Age \) — Age in years

Explanation: The equation accounts for differences in metabolism between genders and how metabolism changes with age, weight, and height.

3. Importance of BMR Calculation

Details: Knowing your BMR helps determine daily calorie needs for weight maintenance, loss, or gain. It's the foundation for most calorie requirement calculations.

4. Using the Calculator

Tips: Enter weight in kg, height in cm, and age in years. For accurate results, measure weight in the morning before eating and after using the bathroom.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is the Harris-Benedict equation?
A: It's about 70% accurate for most people. More accurate methods include indirect calorimetry, but this requires special equipment.

Q2: What's the difference between BMR and RMR?
A: BMR (Basal Metabolic Rate) is measured in a lab under strict conditions. RMR (Resting Metabolic Rate) is similar but measured under less strict conditions and is typically about 10% higher.

Q3: Why do men and women have different equations?
A: Men generally have more muscle mass and less body fat than women of the same weight, leading to higher metabolic rates.

Q4: How does age affect BMR?
A: BMR typically decreases by 1-2% per decade after age 20 due to loss of muscle mass and changes in hormonal and neurological processes.

Q5: Should I use this for weight loss planning?
A: While useful as a starting point, actual calorie needs may vary based on activity level, body composition, and other factors. Consult a nutritionist for personalized advice.