Harris-Benedict Calorie Calculator

Harris Benedict calorie calculator

Your gender:

Enter your age

Enter your height

Enter your weight

Select your activity level:

Select your goal:

Level	kcal/day

This is a reliable calculator to estimate daily calorie consumption in a person. The Harris-Benedict formula was designed for this purpose. This automatic calculator uses the Harris-Benedict formula to estimate your total daily caloric expenditure. You can also estimate the calories needed to gain or lose weight, as well as to gain muscle.

The Harris Benedict equations for estimating basal energy expenditure were developed in the early 20th century from research at the Nutrition Laboratory of the Carnegie Institution of Washington, under the direction of Francis G. Benedict, with the aim of establishing reference standards for comparing the basal energy expenditure of people with different diseases (2).

How to use our Harris-Benedict calculator 2024?

The Harris – Benedict formula was developed in 1918. This formula is used to calculate the calories needed for basal metabolism and physical activity. Specifically, the most commonly used variant is the one proposed by Mifflin and St Jeor in 1990 based on a revision of the original. Represents the Basal Metabolic Rate (BMR), also known as Basal Metabolic Rate, which is the amount of energy needed to maintain the body’s vital functions at rest. This formula takes into account factors such as gender, weight, height, and age. Counting calories is critical, as there is no single variable more important for controlling obesity than daily caloric intake (3).

A fundamental principle of nutrition and metabolism itself is that body weight change is associated with an imbalance between the energy content of the food consumed and the energy used by the body to maintain basic processes, such as keeping us alive, in addition to all the movement performed. (4)

Based on this premise, whatever our goal, whether it is to lose, gain, or maintain our weight, we must know two data: our caloric expenditure, in order to subsequently perform a calorie count adapted to our goals.

This Harris Benedict calculator allows you to calculate the number of calories required for basal metabolism as well as the expenditure caused by daily physical activity, being one of the most used today. It also includes a variable that allows you to calculate, depending on the goals, the calories that should be consumed to lose weight, maintain weight, or increase it. The Harris-Benedict formula is widely used to calculate the daily calories required for both basal metabolism and physical activity. This equation has evolved, and the one most commonly used today is the one revised by Mifflin and St. Jeor in 1990, based on an update of the original.

In summary, the Harris-Benedict formulas are useful for estimating the daily calories needed for basal metabolism and, by extension, for calculating the Daily Energy Expenditure based on activity factors. Next, we will explore this formula, its applications, limitations, and other alternatives that may be useful for athletes and people who want to control their weight.

Explanation of the Harris-Benedict formula

Fundamentals of the Harris Benedict calculator

The fundamentals of the original formula are based on the measurement of the basal metabolic rate, where Harris and Benedict developed the equations using data from indirect calorimetry, which is a method that measures the exchange of respiratory gases in order to calculate the amount of energy the body consumes at rest (1).

Harris and Benedict relied on four main factors:

Body weight (in kg), reflecting the amount of body mass that requires energy to maintain.
Height (in cm): which represents a component of body size.
Age (in years), because it was observed that the basal metabolic rate decreases with age.
Gender: due to physiological differences between the two.

The original formula is as follows (1):

Gender	REE Formula
Men	REE = 66.5 + (13.75 × weight in kg) + (5.003 × height in cm) – (6.755 × age in years)
Women	REE = 655.1 + (9.563 × weight in kg) + (1.850 × height in cm) – (4.676 × age in years)

The Harris-Benedict formula provides what is known as Basal Metabolic Rate (BMR), which shows the amount of calories (energy) needed to maintain the body’s vital functions at rest.

This equation considers gender, age, weight, and height to calculate basal metabolism and, from there, estimates total caloric expenditure. There is one equation for men and another for women:

•⁠ Men: BMR= 66+(13.75×weight in kg)+(5×height in cm)−(6.75×age in years)

•⁠ Women: BMR= 655+(9.56×weight in kg)+(1.85×height in cm)−(4.68×age in years)

In 1990, as mentioned earlier, this equation was modified by Mifflin and St. Jeor, who updated the formula to improve its accuracy: The current formulas are:

•⁠ Men: BMR= (10×weight in kg)+(6.25×height in cm)−(5×age in years)+5

•⁠ Women: BMR = (10×weight in kg)+(6.25×height in cm)−(5×age in years)−161

Although these formulas are very popular, it is important to keep in mind that they are approximations and may not fit perfectly for every individual. However, individual variations and limitations in their applicability may occur, especially for athletes and people with high physical activity. In such cases, it is advisable to consider alternatives, such as the more recent formulas of Mifflin and St. Jeor, as well as specific formulas for athletes that take into account lean body mass.

There are more accurate tools and methods, such as indirect calorimetry, that can provide more exact estimates.

Comparison with other formulas

In this section, we will make a comparison between the most common formulas for calculating energy expenditure and caloric requirements.

Differences between Harris-Benedict and Mifflin-St Jeor

If we compare the Harris Benedict calculator and the Mifflin-St Jeor formula, we find that the Harris Benedict equation is suitable for predicting resting energy expenditure at the group level, but at the individual level, both methods present clinically significant differences (5).

Specific formulas for athletes

The Harris Benedict calculator is considered the most suitable, presenting the smallest difference with indirect calorimetry (6)

Advantages and limitations of each method

Below is a brief visual comparison of the different equations (5,6,7,8)

Calculation method	Advantages	Limitations
Harris-Benedict	Applicable at the group level, easy to use	Less accurate at the individual level and in specific populations
Mifflin-St Jeor	Accurate for individuals with obesity, current population	Less suitable for athletes or atypical body compositions
Cunningham	Accurate for athletes, considers lean mass	Requires body composition data, less accurate for non-athletes
Katch-McArdle	Suitable for athletes, considers muscle mass	Requires body composition data, less accurate for non-athletes

Practical application of the Harris Benedict calculator

Lose weight

[article ids=”98325″] To achieve this goal, we need to create a caloric deficit. A deficit of 500 kcal per day is recommended for effective weight loss (9). In the case of gaining muscle mass while losing weight, which we could call a “high-quality weight loss,” a consumption of 1.6 – 2.4 g of protein / kg / day is recommended (10).

Gain muscle mass

For muscle gain, a caloric surplus of between 10-20% is suggested, for a weekly weight gain target of 0.25-0.50% (11).

Limitations of the Harris Benedict calculator

The accuracy of the Harris Benedict calculator does not exceed 70% in the clinical context, accuracy which does not improve with the addition of body composition measurements (1).
On the other hand, the Harris Benedict formula has good accuracy for well-nourished patients, but in malnourished patients, the Harris Benedict calculator underestimated resting caloric expenditure (12).

In another study, it was found that the Harris Benedict calculator overestimated the resting metabolic rate by 10-15%, with special implications for women and people with reduced body mass (13).

Although these equations are a useful guide for determining maintenance calories and adjusting caloric intake according to your goals, the results are approximate and may need adjustments based on your progress. It is also crucial to consider other factors such as food quality and nutritional balance to maintain a healthy and sustainable diet.

The Harris Benedict calculator is a theoretical form, and it is useful for the initial estimation of basal energy expenditure and daily caloric needs, but it is recommended to complement it with professional advice or more accurate methods such as indirect calorimetry when greater precision is needed, as it has been found that the formula itself has limitations in terms of accuracy.

Frequently asked questions

What is the Harris-Benedict calculator for calories?

The Harris-Benedict calculator for calories estimates the daily calories needed to maintain, lose, or gain weight based on the basal metabolic rate (BMR) and the level of physical activity.

How does the Harris-Benedict formula calculate calories?

The formula calculates the basal metabolic rate (BMR) using age, weight, height, and gender, and then multiplies the BMR by a factor according to the level of physical activity to estimate the necessary calories.

What is the Harris-Benedict calorie calculator for?

It is used to calculate the daily calories needed for different goals such as maintaining weight, losing weight, or gaining muscle, adjusting caloric intake according to the level of activity.

What data is needed to use the Harris-Benedict calorie calculator?

It needs the age, weight, height, gender, and the level of physical activity of the person to calculate the recommended daily calories.

Is the Harris-Benedict calorie calculator suitable for everyone?

It is suitable for most, but it may be less accurate for elite athletes, people with medical conditions, or atypical metabolisms.

How many calories should I consume to lose weight according to Harris-Benedict?

To lose weight, it is recommended to reduce 15-20% of the calories calculated with Harris-Benedict, always adjusting according to individual needs.

How does physical activity affect calorie calculation in the Harris-Benedict formula?

Physical activity increases the number of necessary calories, with different multiplier factors that adjust the BMR according to the level of activity.

What is the difference between BMR and total caloric requirement in Harris-Benedict?

The BMR is the amount of calories needed at rest. The total caloric requirement is calculated by multiplying the BMR by an activity factor to reflect the actual caloric expenditure.

Bibliographic references

1. Bendavid, I., Lobo, D. N., Barazzoni, R., Cederholm, T., Coëffier, M., de van der Schueren, M., Fontaine, E., Hiesmayr, M., Laviano, A., Pichard, C., & Singer, P. (2021). The centenary of the Harris-Benedict equations: How to assess energy requirements best? Recommendations from the ESPEN expert group. Clinical Nutrition (Edinburgh, Scotland), 40(3), 690–701.

1. Frankenfield, D. C., Muth, E. R., & Rowe, W. A. (1998). The Harris-Benedict studies of human basal metabolism: history and limitations. Journal of the American Dietetic Association, 98(4), 439–445.

1. Bernardin, C. P., & Moller, A. (2013). Recommended daily caloric intake. FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology, 27(S1).

1. Hall, K. D., Heymsfield, S. B., Kemnitz, J. W., Klein, S., Schoeller, D. A., & Speakman, J. R. (2012). Energy balance and its components: implications for body weight regulation. The American Journal of Clinical Nutrition, 95(4), 989–994.

1. Amirkalali, B., Hosseini, S., Heshmat, R., & Larijani, B. (2008). Comparison of Harris Benedict and Mifflin-ST Jeor equations with indirect calorimetry in evaluating resting energy expenditure. Indian Journal of Medical Sciences, 62(7), 283–290.

1. Santos Sena, M., Ribeiro de Souza, M. L., & Capistrano Junior, V. L. M. (2021). Resting energy expenditure in CrossFit® participants: Predictive equations versus indirect calorimetry. International journal of kinesiology and sports science, 9(2), 7.

1. Dobratz, J. R., Sibley, S. D., Beckman, T. R., Valentine, B. J., Kellogg, T. A., Ikramuddin, S., & Earthman, C. P. (2007). Predicting energy expenditure in extremely obese women. JPEN. Journal of Parenteral and Enteral Nutrition, 31(3), 217–227.

1. Ducharme, J. B., Fennel, Z. J., Pike, B., Coleman, A., Mermier, C. M., Lauver, J. D., Guilkey, J. P., & Johnson, K. E. (2021). Comparison of resting metabolic rate prediction equations in college-aged adults. Applied Physiology Nutrition and Metabolism, 46(7), 711–718.

1. Carels, R. A., Young, K. M., Coit, C., Clayton, A. M., Spencer, A., & Hobbs, M. (2008). Can following the caloric restriction recommendations from the Dietary Guidelines for Americans help individuals lose weight? Eating Behaviors, 9(3), 328–335.

1. Hector, A. J., & Phillips, S. M. (2018). Protein recommendations for weight loss in elite athletes: A focus on body composition and performance. International Journal of Sport Nutrition and Exercise Metabolism, 28(2), 170–177.

1. Iraki, J., Fitschen, P., Espinar, S., & Helms, E. (2019). Nutrition recommendations for bodybuilders in the off-season: A narrative review. Sports, 7(7), 154.

1. Roza, A. M., & Shizgal, H. M. (1984). The Harris Benedict equation reevaluated: resting energy requirements and the body cell mass. The American Journal of Clinical Nutrition, 40(1), 168–182.

1. Garrel, D. R., Jobin, N., & de Jonge, L. H. (1996). Should we still use the Harris and Benedict equations? Nutrition in Clinical Practice: Official Publication of the American Society for Parenteral and Enteral Nutrition, 11(3), 99–103.