BMR Calculator - Basal Metabolic Rate Calculator

BMR Calculator

• The Basal Metabolic Rate (BMR) is the minimum number of calories that your body needs to perform basic functions, such as breathing and maintaining body temperature.
• Your BMR is influenced by several factors, including your age, sex, weight, and height.
• Knowing your BMR can be useful for a variety of reasons, including weight loss, weight gain, and maintaining a healthy weight.

 

BMR Calculator Formula

The three equations used to calculate the BMR calculator in different phases are below

1. Mifflin-St Jeor Equation
2. Revised Harris-Benedict Equation
3. Katch-McArdle Formula

 

1. Mifflin-St Jeor Equation

 

For Men

BMR = 10W + 6.25H - 5A + 5

 

For Women

BMR = 10W + 6.25H - 5A - 161

 

2. Revised Harris-Benedict Equation

 

For Men

BMR = 13.397W + 4.799H - 5.677A + 88.362

 

For Women

BMR = 9.247W + 3.098H - 4.330A + 447.593

 

3. Katch-McArdle Formula

BMR = 370 + 21.6(1 - F)W

 

where

W is body weight in kg

H is body height in cm

A is age

F is body fat in percentage

 

BMR Calculator To Lose Weight

• Once you have calculated your BMR, you can use it to estimate the number of calories you need to maintain your current weight.
• This is known as your daily caloric needs.
• To calculate your daily caloric needs, you can multiply your BMR by a factor that takes into account your activity level.
• For example, if you have a sedentary lifestyle (little or no exercise), you can multiply your BMR by 1.2.
• If you have a lightly active lifestyle (light exercise/sports 1-3 days/week), you can multiply your BMR by 1.375.
• If you have a moderately active lifestyle (moderate exercise/sports 3-5 days/week), you can multiply your BMR by 1.55.
• And if you have a very active lifestyle (hard exercise/sports 6-7 days a week), you can multiply your BMR by 1.725.

 

BMR Calculator Calories

• It's important to note that these are just estimates and that your actual daily caloric needs may be different.
• There are many other factors that can influence your caloric needs, including your body composition, hormonal balance, and the types of foods you eat.
• It's also important to remember that weight loss or gain is not just about calories in versus calories out.
• It's also about the quality of the calories you eat and the types of activities you engage in.
• In general, to lose weight, you need to create a calorie deficit by eating fewer calories and increasing your physical activity.
• To gain weight, you need to create a calorie surplus by eating more calories and decreasing your physical activity.
• And to maintain your weight, you need to eat the right amount of calories for your body's needs and engage in regular physical activity.
• It's always a good idea to talk to a healthcare provider or registered dietitian before making any changes to your diet or exercise routine.
• They can help you determine the right caloric intake and activity level for your individual needs and goals.

 

BMR Calculator Formula For Men & Women

• To calculate your BMR, you will need to know your weight in kilograms, your height in centimeters, and your age in years.
• You can then use the following formulas to calculate your BMR:

 

BMR Calculator Formula For Men

BMR = 88.362 + (13.397 x weight in kg) + (4.799 x height in cm) - (5.677 x age in years)

 

BMR Calculator Formula For Women

BMR = 447.593 + (9.247 x weight in kg) + (3.098 x height in cm) - (4.330 x age in years)

 

Age Range	Gender	BMR Range (kcal/day)
18-29	Male	1,800-2,400
18-29	Female	1,400-2,000
30-59	Male	1,600-2,200
30-59	Female	1,200-1,800
60+	Male	1,400-2,000
60+	Female	1,200-1,600

 

 

BMR Parameters & Variables

 

Muscle Mass

• Aerobic exercises, such as running or cycling, have no effect on BMR.
• However, anaerobic exercises, such as weight lifting, indirectly lead to a higher BMR because they build muscle mass, increasing resting energy consumption.
• The more muscle mass in the physical composition of an individual, the higher the BMR required to sustain their body at a certain level.

 

Age

• The more elderly and limber an individual, the lower their BMR, or the lower the minimum caloric intake required to sustain the functioning of their organs at a certain level.

 

Genetics

• Hereditary traits passed down from ancestors influence BMR.

 

Weather

• Cold environments raise BMR because of the energy required to create a homeostatic body temperature.
• Likewise, too much external heat can raise BMR as the body expends energy to cool off internal organs.
• BMR increases approximately 7% for every increase of 1.36 degrees Fahrenheit in the body's internal temperature.

 

Diet

• Small, routinely dispersed meals increase BMR.
• On the other hand, starvation can reduce BMR by as much as 30%.
• Similar to a phone that goes into power-saving mode during the last 5% of its battery
• A human body will make sacrifices such as energy levels, moods, upkeep of bodily physique, and brain functions in order to more efficiently utilize what little caloric energy is being used to sustain it.

 

Pregnancy

• Ensuring the livelihood of a separate fetus internally increases BMR.
• This is why pregnant women tend to eat more than usual.
• Also, menopause can increase or decrease BMR depending on hormonal changes.

 

Supplements

• Certain supplements or drugs raise BMR, mostly to fuel weight loss.
• Caffeine is a common one.

 

Resting Metabolic Rate

• The resting metabolic rate is the total number of calories burned when your body is completely at rest.
• RMR supports breathing, circulating blood, organ functions, and basic neurological functions.
• It is proportional to lean body mass and decreases approximately 0.01 kcal/min for each 1% increase in body fatness.

 

MIFFLIN-ST JEOR EQUATION

The Mifflin-St Jeor equation, created in the 1990s, provided an alternative and more valid estimate of RMR.

 

The equations for males and females 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

 

• Using that same example and this equation, the female’s RMR would equal approximately 1,356 calories.

 

HARRIS AND BENEDICT EQUATION

• The Harris and Benedict (H&B) equation created in 1918 and amended in 1984 remains widely used today.
• While it was intended to measure basal metabolic rate (BMR) or basal energy expenditure (BEE), they are used interchangeably with RMR.
• Technically, BMR measures energy expenditure in a darkened room (reclining position) after eight hours of sleep and following a 12-hour fast whereas RMR measurements are less restrictive and reflect the body’s resting energy expenditure after an overnight fast.

 

The revised H&B equations for males and females

 

Men

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

 

Women

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

 

• As an example, for a 38-year-old female, who stands 5’6” (167.6 cm) and weighs 145 pounds (65.9 kg), her BMR or RMR would equal approximately 1,411 calories.
• This is the energy needed daily to maintain normal physiological function.

 

Basal Metabolic Rate

Below are Some Terms given to know after calculating Basal Metabolic Rate.

 

Body Fat Calculator

• The scientific term for body fat is "adipose tissue" which is the main term to use and calculate Body Fat Calculator.
• Adipose tissue serves a number of important functions. Its primary purpose is to store lipids from which the body creates energy.
• In addition, it secretes a number of important hormones and provides the body with some cushioning as well as insulation.
• Body fat includes essential body fat and storage body fat.
• Essential body fat is a base level of fat that is found in most parts of the body. It is necessary fat that maintains life and reproductive functions.
• The amount of essential fat differs between men and women and is typically around 2-5% in men, and 10-13% in women.
• The healthy range of body fat for men is typically defined as 8-19%, while the healthy range for women is 21-33%.

 

The American Council on Exercise Body Fat Categorization

Description	Women	Men
Essential fat	10-13%	2-5%
Athletes	14-20%	6-13%
Fitness	21-24%	14-17%
Average	25-31%	18-24%
Obese	32+%	25+%

 

Jackson & Pollard Ideal Body Fat Percentages

Age	Women	Men
20	17.7%	8.5%
25	18.4%	10.5%
30	19.3%	12.7%
35	21.5%	13.7%
40	22.2%	15.3%
45	22.9%	16.4%
50	25.2%	18.9%
55	26.3%	20.9%

 

Daily Calorie Requirement

Daily calorie needs largely depend upon the Activity factor. After calculating the BMR, multiply the result with an activity factor to know about the daily calorie needs.

 

Activity Level	Daily Calorie Requirement
Sedentary Lifestyle: little or no exercise	BMR * 1.2
Slightly Active Lifestyle: Exercise 1-3 times/week	BMR * 1.375
Moderately Active Lifestyle: Exercise 4-5 times/week	BMR * 1.55
Active Lifestyle: Daily exercise or intense exercise 3-4 times/week	BMR * 1.725
Very Active Lifestyle: Intense exercise 6-7 times/week	BMR * 1.9

 

Daily Energy Expenditure

• TDEE stands for total daily energy expenditure.
• It is the total energy that a person uses in a day.
• TDEE is hard to measure accurately and varies day by day.
• More often, it is estimated using factors such as a person's basal metabolic rate (BMR), activity level, and the thermic effect of food.

 

Importance of BMR

• An alternative to the BMR formulas is to simply follow the commonly suggested minimal numbers of 1,000-to-1,200 calories for women and 1,200-to-1,600 calories for men.
• These numbers, however, provide estimates at best because the macronutrient composition of a diet (e.g., high protein, fiber), timing and even physical form of food (i.e., liquid versus solid) can all impact TEF, absorption and ultimately BMR.

 

HUNGER SCALE

• The sensation of hunger is another viable option to use as a guide, but the sensation of hunger is considered plastic (i.e., modifiable) and for some, confusion exists in distinguishing hunger from appetite.
• Regardless, the hunger scale can help you gain a sense of whether you are providing adequate food calories to your body to avoid starvation – in other words, the opportunity to listen to your body.

 

Hunger Score	Description
1	Starving, weak, dizzy, headache, lack of concentration
2	Irritable, cranky, very hungry, low energy, lots of stomach growling
3	Strong urge to eat, stomach growls a little
4	Feeling a little hungry – thinking about food
5	The body feels fueled (starting to feel satisfied), neither hungry nor full
6	Fully satisfied - little full, but pleasantly full
7	A little uncomfortable, but could still eat additional item
8	Feeling stuffed
9	Feel very bloated - very uncomfortable, stomach hurts
10	Feel sick from overeating

 

• Ideally, you would spend your waking hours between hunger scores of 4-and-6.
• In other words when a ‘4’ is reached, eat something to prevent dropping to the ‘3’ where ravenous, binge eating is more likely, but learn to stop at a ‘6’ rather than a ‘7’ or higher as many individuals do.

 

Hunger VS Appetite

Lastly, take the time to understand some basic differences between hunger and appetite which are outlined below

 

Hunger

• It is considered a biological response to replenish the body’s energy reserves.
• Protects us from starvation.
• Usually triggered by an event occurring below the neckline:
• Low blood sugar.
• Empty (growling) stomach.
• Hormone fluctuations.
• Need to warm body (hypothermia).
• Gradual onset appears after several hours without food and typically diminishes after eating.
• It is generally satisfied by almost any food that provides energy (calories).

 

Appetite

• It is considered a desire or interest to eat a specific food.
• Usually triggered by an event occurring above the neckline consciously or subconsciously:
• Thoughts, emotions, and moods.
• Social (e.g., happy hour)
• Cultural (e.g., family)
• Environmental (e.g., walking into a bakery).
• More rapid onset and often independent of hunger.
• Not time-dependent and may persist after eating.
• Usually only satisfied by a specific food (e.g., sweet, salty) which may then evoke emotions and thoughts afterward (e.g., pleasure, guilt, shame).

 

Ideal BMR For Your Age

Traditionally the normal range of your ideal BMR was determined by age and gender. Here are the ‘DuBois normal standards for BMR’ breakdown according to your age bracket:

Age	Male (calories per hour)	Female (calories per hour)
20–29	39.5	37.0
30–39	39.5	36.5
40–49	38.5	36.5
50–59	37.5	35.0
60–69	36.5	34.0
70–79	35.5	33.0

 

Summary

Overall BMR Calculator will help you to find out how much average calories person should intake for a helathy life. Check More Medical Health Related Calculator on Drlogy Calculator to get exact health solution.

 

Reference

• Basal metabolic rate by wikipedia [1].
• Basal metabolic rate: What it is, calculation, and more [2].