Schofield Equation Calculator

The Schofield equation refers to a series of equations developed by Dr. William Schofield in the mid-20th century to estimate Basal Metabolic Rate (BMR) and Total Energy Expenditure (TEE) in adults. These equations were based on a large dataset of metabolic rate measurements from various populations.

The Schofield equations are divided into different formulas tailored for different age groups and genders. They estimate BMR based on factors such as age, gender, and weight. The most commonly used version of the Schofield equations is the one published by the Food and Agriculture Organization (FAO) of the United Nations in 1985, which provides equations for estimating BMR in adults aged 18-65+ years.

The Schofield equation calculator relies on a series of formulas used to estimate Basal Metabolic Rate (BMR) in adults. The most commonly used version of the Schofield equations provides separate formulas for different age groups and genders.

The general form of the Schofield equation for estimating BMR in adults is:

For men: BMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) - (5.677 × age in years)

For women: BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) - (4.330 × age in years)

Alternatively, the Schofield equation includes versions that categorize individuals into different age groups, each with its own specific formula for estimating BMR. Here's an example of how BMR is estimated using the Schofield equation with different brackets for different age groups:

1. For men aged 18-30 years: BMR = 15.1 × weight in kg + 692
2. For men aged 31-60 years: BMR = 11.5 × weight in kg + 873
3. For men aged 61-90 years: BMR = 11.9 × weight in kg + 700
4. For women aged 18-30 years: BMR = 14.7 × weight in kg + 496
5. For women aged 31-60 years: BMR = 8.7 × weight in kg + 829
6. For women aged 61-90 years: BMR = 9.2 × weight in kg + 688

You can simply enter weight, age and gender in your preferred units in the calculator above to get your result.

The Schofield equation calculator provides estimates for BMR. But what about TDEE? It is important to know there is a fundamental difference between the two:

• BMR (Basal Metabolic Rate): BMR represents the number of calories your body needs to maintain basic physiological functions while at rest. It is calculated using formulas that take into account factors such as age, gender, weight, and sometimes height. The Schofield equation provides estimates of BMR based on these factors.
• TDEE (Total Daily Energy Expenditure): TDEE represents the total number of calories your body burns in a day, including BMR as well as calories burned through physical activity and the thermic effect of food. It provides a more comprehensive estimate of your daily calorie needs. TDEE is calculated by multiplying your BMR by an activity factor that accounts for your level of physical activity.

In summary, while BMR represents the baseline energy expenditure at rest, TDEE provides a more holistic view of your total daily calorie needs, incorporating both resting metabolic rate and activity level.

Using a Schofield equation calculator to detemine BMR is easy, but you should be aware of some of the limitations of this approach:

• Age and Gender Specificity: The Schofield equation provides separate formulas for different age groups and genders. While this approach allows for some customization, it may not fully capture individual variability in metabolic rate within each age and gender category.
• Assumption of Homogeneity: The Schofield equation assumes that metabolic rate within each age and gender category is homogeneous, meaning that all individuals within the same category have similar metabolic rates. However, metabolic rate can vary significantly among individuals due to factors such as body composition, genetics, and lifestyle.
• Use of Weight Only: Some versions of the Schofield equation use weight as the sole predictor of metabolic rate, without considering other factors such as height or body composition. This may lead to inaccuracies, as individuals with similar weights but different body compositions may have different metabolic rates.
• Population Specificity: The Schofield equation was developed based on data from specific populations and may not be applicable to all demographic groups. For example, the equations may not accurately estimate metabolic rate in individuals from different ethnic backgrounds or geographic regions.
• Static Nature: The Schofield equation provides estimates of metabolic rate at a single point in time and does not account for changes in metabolic rate that may occur over time or in response to factors such as diet, exercise, or illness.

While the Schofield equation has been widely used as a practical tool for estimating metabolic rate, it is important to recognize its limitations and use caution when applying the equations in diverse populations or for individualized assessments.

There are other options other than using a Schofield equation calculator. You can estimate BMR with a couple of other formulas:

• Harris-Benedict equation
• Katch-McArdle equation
• Mifflin-St Jeor equation
• BMR calculator - comparing all formulas

The alternatives rely on different formulas and may produce slightly different estimates.

You can read about the Schofield equation on this Wikipedia article.