How many calories do you naturally burn in a day?

The number of calories you burn each day depends on a variety of factors, including your basal metabolic rate (BMR), activity level, age, weight, height, gender, and muscle mass. Your BMR is the minimum number of calories your body needs to perform essential functions like breathing, circulating blood, regulating body temperature, and other involuntary functions. This accounts for 50-70% of the calories you burn each day. The more active you are, the more calories you’ll burn through exercise and additional movement throughout the day. Generally, adult men burn around 2,500 calories per day, while adult women burn around 2,000 calories per day on average. However, this can vary significantly based on the factors mentioned above.

What is BMR?

Your basal metabolic rate (BMR) is the minimum number of calories your body requires to perform involuntary, life-sustaining functions. It accounts for 50-70% of the calories you burn each day. Some key factors that determine your BMR include:

– Age: BMR generally decreases as you get older.

– Sex: Men tend to have a higher BMR because they have more muscle mass.

– Weight: The more you weigh, the higher your BMR since it takes more energy to sustain bodily functions.

– Height: Taller individuals tend to have a higher BMR.

– Muscle mass: Muscle tissue burns more calories than fat tissue, even at rest.

– Genetics: Some people naturally have a faster metabolism.

– Pregnancy/lactation: BMR increases during pregnancy and breastfeeding to support development.

To determine your BMR, you can use an online calculator that factors in your age, sex, weight, height and activity level. Or you can get tested by a doctor for a more accurate reading. Generally, adult women have a BMR between 1,200-1,600 calories/day, while adult men range from 1,600-2,000 calories/day on average. However, this varies significantly based on the factors above.

Calories burned through activity

In addition to your BMR, you burn extra calories through any movement and exercise. Activities like walking, cleaning, fitness training, fidgeting and maintaining posture all burn calories over the course of a day. The more active you are, the more calories you’ll burn.

Some examples of calorie burn from common activities include:

– Walking (3 mph): 210 calories per 30 minutes
– Light jogging (5 mph): 298 calories per 30 minutes
– Cycling (12-14 mph): 298 calories per 30 minutes
– Swimming laps: 400-500 calories per 30 minutes
– HIIT workout: 300-400 calories per 30 minutes
– Heavy yard work: 300+ calories per hour
– Light housework: 200+ calories per hour

Your activity level can significantly impact your daily calorie burn. Sedentary adults may only burn an extra 200-300 calories through activity, while active adults can burn 500 or more extra calories through exercise and additional movement throughout the day.

How age impacts calories burned

Age can impact your daily calorie burn in several ways:

– BMR naturally decreases with age due to loss of muscle mass. Typically BMR decreases by about 2% per decade after age 20.

– Older adults tend to be less physically active than younger adults on average, resulting in fewer activity-related calories burned.

– The calories needed for growth and development in childhood and adolescence result in higher calorie needs during youth.

– Aging may decrease the thermic effect of food (TEF) – or calories burned through digesting food – by up to 20%.

Some average calorie burn values by age group:

– Children 4-8 years: 1,200-1,600 calories/day
– Teen males 14-18 years: 1,800-2,600 calories/day
– Teen females 14-18 years: 1,200-2,200 calories/day
– Adult males 19-30 years: 2,400-3,000 calories/day
– Adult females 19-30 years: 1,800-2,400 calories/day
– Adult males 30-60 years: 2,200-3,000 calories/day
– Adult females 30-60 years: 1,800-2,400 calories/day
– Adults over 60 years: 1,600-2,400 calories/day

So while calorie needs decrease with age, there is still significant variation based on activity levels and other individual factors. Staying active can help offset the natural decline in BMR as you get older.

Calories burned based on weight

Heavier individuals need more calories just for basic functioning compared to lighter individuals. Some key points on weight and calorie burn:

– BMR increases with body weight since heavier bodies require more energy for basic functions.

– However, obese individuals tend to have lower BMRs relative to their body mass compared to lean individuals.

– Carrying excess weight leads to higher energy requirements for movement and exercise.

– Losing body fat through dieting and exercise leads to a drop in BMR.

Here are some estimates for average calorie burn based on weight status:

– Underweight adult female (<18.5 BMI): 1,600-1,800 calories/day - Healthy weight adult female (18.5-24.9 BMI): 1,800-2,000 calories/day - Overweight adult female (25-29.9 BMI): 2,000-2,200 calories/day - Obese adult female (30+ BMI): 2,000-2,400 calories/day - Underweight adult male (<18.5 BMI): 1,800-2,000 calories/day - Healthy weight adult male (18.5-24.9 BMI): 2,400-2,600 calories/day - Overweight adult male (25-29.9 BMI): 2,600-2,800 calories/day - Obese adult male (30+ BMI): 2,800-3,000+ calories/day A difference of just 10-20 pounds can alter calorie needs by several hundred calories per day. Maintaining a healthy body weight supports metabolic health and appropriate calorie burn.

Effect of height on calories burned

Your height influences your BMR and total daily calorie requirements in a few key ways:

– Taller people have more muscle mass and organ tissue which contribute to a higher BMR.

– Greater height usually correlates to higher weight, which increases calorie needs.

– Taller people burn more calories per movement due to longer limbs and bigger frames.

– Extremely short or tall stature can increase calorie needs due to growth, hormonal factors and stress on the body.

Here are some average calorie burn estimates based on height:

– 4’10” female: 1,700 calories/day
– 5’4″ female: 1,800-2,000 calories/day
– 5’9″ female: 1,900-2,100 calories/day

– 5’4″ male: 2,200-2,400 calories/day
– 5’9″ male: 2,400-2,600 calories/day
– 6’2″ male: 2,600-2,800 calories/day

While these ranges provide averages, substantial differences in age, weight, activity levels and other variables between people of the same height mean height is not on its own a major determining factor of calorie requirements. However, all else being equal, taller individuals need more calories than shorter folks.

Calories burned based on gender

On average, men burn more calories than women each day. Some key differences that impact calorie burn:

– Men naturally have less body fat and more muscle than women, increasing their BMR.

– Male sex hormones like testosterone increase muscle mass and metabolic rate.

– Women’s BMRs decrease during menopause as estrogen levels drop.

– Men tend to be larger and have lower body fat percentages. This leads to higher calorie burn during exercise and activity.

– Pregnancy and breastfeeding increase calorie needs significantly for women.

Estimates for average calorie requirements by gender are:

– Sedentary adult male: 2,200-2,400 calories/day
– Active adult male: 2,800-3,200 calories/day

– Sedentary adult female: 1,600-1,800 calories/day
– Active adult female: 2,000-2,400 calories/day

However, there is significant overlap between genders, particularly among active women and sedentary men. Lifestyle factors including activity, age, height and weight can outweigh gender differences for many individuals.

Calories burned based on muscle mass

Skeletal muscle burns more calories than fat tissue, even at rest. Therefore, individuals with more muscle mass have a higher BMR and total daily calorie expenditure.

– Each pound (0.45 kg) of muscle burns around 6 calories per day at rest, while each pound of fat burns about 2 calories per day.

– Resistance training helps build and maintain muscle, increasing BMR over time.

– Men naturally have more skeletal muscle than women, enabling higher calorie burn.

– Endurance and strength athletes who have trained for years tend to have significantly higher muscle mass and calorie needs.

– Aging leads to gradual loss of muscle if resistance exercise isn’t performed regularly.

Here are some estimates for calorie needs based on muscle mass percentages:

– Female with low muscle mass (15% total weight): 16 calories/pound/day
– Female with average muscle mass (25% total weight): 19 calories/pound/day
– Female athlete with high muscle mass (35% total weight): 22 calories/pound/day

– Male with low muscle mass (25% total weight): 20 calories/pound/day
– Male with average muscle mass (35% total weight): 23 calories/pound/day
– Male athlete with high muscle mass (45% total weight): 26 calories/pound/day

Building muscle through exercise provides long-term metabolic benefits by increasing the number of calories burned each day. It helps offset the drop in BMR that can occur with aging.

Genetic impact on calorie burn

Your genetics can influence your BMR and daily calorie burn to some degree. However, the effects are modest and lifestyle factors tend to have a bigger impact. Areas genetics may influence include:

– BMR: Some people inherited faster or slower metabolisms. But this accounts for just 100-200 calories/day variance on average.

– Body fat distribution: Where fat is stored affects metabolic rate, with visceral belly fat linked to lower BMRs.

– Muscle fibers: The ratio of slow to fast twitch muscle fibers you have can alter muscle metabolism.

– Hormone levels: Genetics influence testosterone, thyroid and other hormone levels tied to metabolic rate.

– Non-exercise activity: Fidgeting and spontaneous activity levels may be innate.

– Energy absorption: How efficiently your body extracts energy from food can vary.

While genetic potential exists, factors like diet, exercise, stress and sleep tend to have a much greater impact on calorie burn than inherited traits. BMRs can vary up to 600-800 calories/day between people due to lifestyle differences. So focus on optimizing the variables you can control through healthy habits.

Effect of pregnancy and breastfeeding on calorie burn

– Pregnancy causes an increase in BMR of 10-15% to support fetal growth and development.

– Calorie needs spike in the second and third trimester due to rapid baby weight gain. An extra 300 calories/day is usually recommended.

– Breastfeeding mothers require about 500 extra calories per day to support milk production.

– BMR remains elevated while breastfeeding and doesn’t return to pre-pregnancy baseline until weaning.

– Increased food intake leads to increased calories burned through the thermic effect of food during pregnancy and lactation.

Here are typical calorie requirements during and after pregnancy:

– First trimester: No extra calories needed
– Second trimester: Add 300 calories/day
– Third trimester: Add 300 calories/day = 450 extra calories/day total
– Breastfeeding: Add 500 calories/day
– After weaning: Subtract 350-500 calories/day from second/third trimester needs

Working with a doctor can help determine appropriate calorie intake as needs vary significantly person to person during this time depending on activity levels and maternal health.


Your daily calorie burn is dependent on a variety of interrelated factors. These include your BMR, activity levels, age, height, weight, muscle mass and gender. BMR accounts for 50-70% of calories burned, while activity makes up the remainder. Adult men tend to burn around 2,500 calories per day, while adult women burn 2,000 calories on average. However, this can range from 1,600-3,000+ calories/day for adults depending on individual lifestyle and demographic factors. Optimizing your diet, exercise regimen, sleep and stress levels can help support a healthier metabolism over time.


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