Apr 20, 20235 min read

Basal Metabolic Rate (BMR)

BMR stands for "Basal Metabolic Rate".

Yellow notebook with writing on it that says BMR basal metabolic rate. It has an equations written as well. The notebook is sitting on a wooden desk with tea.

What is Basal Metabolic Rate (BMR)?

Basal Metabolic Rate, or BMR, is the amount of energy your body uses to carry out its essential functions while at rest. These functions include:

maintaining body temperature
breathing
circulating blood
producing cells
keeping your organs functioning properly

BMR accounts for approximately 60-75% of your total daily energy expenditure, which is why it's crucial to understand its role in weight management and overall health. Basal Metabolic Rate, or BMR, is the amount of energy your body uses to carry out its essential functions while at rest. These functions include:

Factors affecting BMR

Several factors influence your BMR, including:

age
gender
body size and composition
climate and temperature
genetic factors.

Age

As you age, your BMR typically decreases. This decline is partly due to a reduction in muscle mass and an increase in body fat. Muscle burns more calories than fat, so having less muscle mass can lead to a lower BMR.

Gender

Men generally have a higher BMR than women. This difference is primarily because men typically have more muscle mass and less body fat than women.

Body size and composition

Larger bodies require more energy to maintain their basic functions. As a result, individuals with more muscle mass or a larger frame will have a higher BMR. Conversely, individuals with less muscle mass or a smaller frame will have a lower BMR.

Climate and temperature

Cold environments can increase BMR, as the body works harder to maintain its core temperature. Similarly, hot environments can cause a slight increase in BMR due to increased sweat production and blood circulation.

Genetic factors

Your genes can influence your BMR, with some individuals having a naturally higher or lower BMR due to their genetic makeup.

Cell-Phone screen that calculates basal metabolic rate with weight, height, and age. A tape measurer is behind the phone.

How to Calculate Your BMR

Calculating your basal metabolic rate (BMR) can help you understand how many calories your body needs to keep functioning. Knowing your BMR can help you create a more realistic and effective nutrition and fitness plan to reach your goals. It can also help you better understand how many calories your body needs to maintain your current weight, as well as how many calories you need to lose or gain weight. Additionally, knowing your BMR can help you make more informed decisions about your nutrition and activity levels.

Common BMR equations

There are several equations used to estimate BMR, with the Mifflin-St Jeor Equation and the Harris-Benedict Equation being the most widely recognized.

Mifflin-St Jeor Equation

The Mifflin-St Jeor Equation is considered more accurate for estimating BMR and is as follows:

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

Harris-Benedict Equation

The Harris-Benedict Equation, though slightly less accurate than the Mifflin-St Jeor Equation, is still commonly used:

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)

BMR calculators

Online BMR calculators are widely available and easy to use. By inputting your age, gender, weight, and height, these calculators can provide an estimate of your BMR using one or more of the equations mentioned above.

How BMR Affects Weight Management

BMR plays an important role in weight management because it is a determining factor in how many calories your body needs to maintain its current weight. Thus, if you want to manage your weight, you should be aware of your BMR and make sure to maintain a caloric intake that is appropriate for your BMR.

BMR and caloric intake

Understanding your BMR can help you manage your weight more effectively. To maintain your current weight, you need to consume enough calories to meet your daily energy expenditure, which includes your BMR and additional calories burned through physical activity.

If you consume more calories than your body needs, you will gain weight. On the other hand, if you consume fewer calories than your body needs, you will lose weight. Knowing your BMR can help you determine the appropriate caloric intake to achieve your weight management goals.

BMR and physical activity

Physical activity is essential for weight management and overall health. Regular exercise can increase your total daily energy expenditure, which makes it easier to create a calorie deficit and lose weight. Additionally, exercise can help counteract the decline in BMR associated with aging by preserving muscle mass.

A caucasian hand pointing to 4 circle diagrams about weight management.

Improving Your BMR

Luckily, it is possible to improve your BMR. You can improve your BMR by:

doing regular physical activity
eating a balanced diet
getting adequate sleep
reducing stress.

Increase muscle mass

Increasing your muscle mass through strength training exercises can help boost your BMR. As previously mentioned, muscle burns more calories than fat, so having more muscle mass will increase the number of calories your body burns at rest.

Optimize nutrition

Eating a well-balanced diet can support a healthy BMR. Consuming adequate protein can help maintain muscle mass, while a diet rich in vitamins and minerals can support your body's essential functions.

Adequate Sleep

Adequate sleep helps to maintain a healthy weight, which is important for maintaining a healthy BMR. Additionally, adequate sleep helps to regulate hormones that control metabolism, allowing for the body to more efficiently use energy. Finally, adequate sleep helps to reduce stress, which can cause the body to burn more calories than it should.

Reducing Stress

Reducing stress can help to improve BMR by lowering levels of the hormone cortisol in the body. High levels of cortisol can interfere with the body's ability to effectively use energy, resulting in a higher BMR. When stress levels are low, cortisol levels are lower and the body is better able to use energy efficiently, resulting in a lower BMR.

Conclusion

Your Basal Metabolic Rate plays a critical role in weight management and overall health. By understanding the factors that affect BMR and learning how to calculate it, you can make more informed decisions about your caloric intake, exercise, and lifestyle choices. By focusing on increasing muscle mass and optimizing your nutrition, you can improve your BMR and support your long-term health goals.

FAQs

1. What is Basal Metabolic Rate (BMR)?

BMR is the amount of energy your body uses to carry out its essential functions while at rest, such as maintaining body temperature, circulating blood, and keeping your organs functioning.

2. How does BMR affect weight management?

BMR determines the number of calories your body needs to maintain its basic functions. By understanding your BMR, you can determine the appropriate caloric intake to maintain, lose, or gain weight.

3. How can I calculate my BMR?

You can calculate your BMR using equations such as the Mifflin-St Jeor Equation or the Harris-Benedict Equation, or by using an online BMR calculator.

4. Can I increase my BMR?

Yes, you can increase your BMR by increasing muscle mass through strength training exercises and optimizing your nutrition with a well-balanced diet.

5. Why does BMR decrease with age?

BMR decreases with age due to a reduction in muscle mass and an increase in body fat. Since muscle burns more calories