Knowing how to calculate your calorie needs is important for maintaining your body's energy balance, whether you want to lose weight, maintain your ideal body shape, or gain muscle mass.
However, everyone's calorie needs vary based on age, gender, weight, height, and daily activities. The following article explains how to accurately calculate your daily calorie intake, from the BMR (Basal Metabolic Rate) formula to physical activity factors. So, let's take a look!
What Are Calories?
Calories are a unit of measurement for energy, particularly in food and beverages. They are generally written in kilocalories (kcal); for example, 500 calories equals 500 kcal.
The number of calories consumed each day plays a vital role in regulating body weight. If you want to lose weight, you need to consume fewer calories than your body burns.
Conversely, to gain weight, you need to consume more calories than your body needs. While this may sound simple, many other factors also influence weight fluctuations, such as age, genetics, hormones, and certain medical conditions.
Daily Calorie Needs According to the Recommended Dietary Allowances
It is important to note that calorie requirements vary from person to person. These differences are typically influenced by age, gender, weight, height, and physical activity level.
Based on Minister of Health Regulation Number 28 of 2019 concerning Recommended Dietary Allowances (RDA), the following are the average daily calorie needs for each person based on age and gender:
Babies and Children:
- Age 0–5 months: 550 kcal.
- Age 6–11 months: 800 kcal.
- Age 1–3 years: 1,350 kcal.
- Age 4–6 years: 1,400 kcal.
- Age 7–9 years: 1,650 kcal.
Men:
- Age 10–12 years: 2,000 kcal.
- Age 13–15 years: 2,400 kcal.
- Age 16–18 years: 2,650 kcal.
- Age 19–29 years: 2,650 kcal.
- Age 30–49 years: 2,550 kcal.
- Age 50–64 years: 2,150 kcal.
- Ages 65–80: 1,800 kcal.
- Ages >80: 1,600 kcal.
Women:
- Ages 10–12: 1,900 kcal.
- Ages 13–15: 2,050 kcal.
- Ages 16–18: 2,100 kcal.
- Ages 19–29: 2,250 kcal.
- Ages 30–49: 2,150 kcal.
- Ages 50–64: 1,800 kcal.
- Ages 65–80: 1,550 kcal.
- Ages >80: 1,400 kcal.
Women with special conditions, such as pregnancy or breastfeeding, need additional daily calories. Pregnant women need an extra 180 kcal in the first trimester and 300 kcal in each of the second and third trimesters.
Meanwhile, breastfeeding mothers need an additional 330 kcal per day during the first six months of breastfeeding, and 400 kcal per day during the second six months.
In addition to daily calories, adequate fluid intake is essential to reduce the risk of dehydration. To meet your daily fluid needs, make sure you always have AQUA Gallon on hand!
But why AQUA? AQUA is 100% pure mountain water that contains natural minerals without any added substances. AQUA also comes from protected sources whose natural mineral composition is protected. This is what makes AQUA taste cold when consumed, even without refrigeration.
In addition to ensuring your daily calorie needs are met, do not forget to meet your daily hydration needs!
How to Calculate Daily Calorie Requirements
To determine how many calories your body needs, follow these two steps: calculate your BMR and adjust it based on your daily activity level.
If you want a more practical approach, you can also use an online BMR calculator that references these formulas as a starting guide. Here are some ways to calculate your daily calorie needs.
1. Calculate BMR
BMR (Basal Metabolic Rate) is the number of calories your body needs to perform basic functions while at complete rest, such as breathing and blood circulation. There are three commonly used formulas for calculating BMR, which are:
Harris Benedict Formula
- Men: BMR = 66 + (13.7 × weight in kg) + (5 × height in cm) – (6.8 × age in years).
- Women: BMR = 655 + (9.6 × weight in kg) + (1.8 × height in cm) – (4.7 × age in years).
Mifflin-St. Jeor Formula
- 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.
WHO/FAO Formula
This formula varies by age and gender and uses reference tables adjusted for specific age groups. Here are some examples:
- Men aged 18–30 years:
BMR = 15.3 × weight (kg) + 679
- Women aged 18–30 years:
BMR = 14.7 × weight (kg) + 496
2. Adjust for Activity Level
After determining your BMR, the next step is to adjust it for your daily physical activity level. The formula is as follows:
Calorie Requirements = BMR × Activity Factor
Here is an explanation of the activity factors that can be used:
- Less active (×1.2): Rarely or never exercises.
- Lightly active (×1.375): Exercises lightly 1–3 times a week.
- Moderately active (×1.55): Engages in moderate exercise 3–5 times a week.
- Very active (×1.725): Engages in strenuous exercise 6–7 times a week.
- Extremely active (×1.9): Engages in very strenuous exercise daily or has a physically demanding job.
Example of Daily Calorie Calculation
To better understand how to calculate calories for a diet or general daily calorie needs, here is a simple example calculation.
For example, a 25-year-old woman weighing 60 kg, measuring 160 cm, and having a mildly active physical activity level, such as exercising 1–3 times per week.
Her calorie requirement can be calculated by starting with her BMR using the Harris-Benedict formula for women:
BMR = 655 + (9.6 × 60) + (1.8 × 160) – (4.7 × 25) = 1,401.5 kcal.
Next, because her activity level is classified as mildly active, the BMR is multiplied by the activity factor, which is 1.375:
1,401.5 × 1.375 = 1,927.06 kcal.
After rounding, the woman's total daily calorie requirement is approximately 1,900 kcal.
Factors That Affect Calorie Needs
Each person's calorie requirement is influenced not only by physical activity but also by other factors. This is what makes calorie requirements differ between individuals. Some of the factors that influence this include:
- Gender.
- Age.
- Height.
- Metabolic condition.
- Gut microbiome.
- Health condition and ongoing treatment.
Even if you know how to calculate your calorie needs, it is best to consult a nutritionist or specialist doctor for more accurate results.
The previous calculation example is only an estimate that can be used as a rough guide.
That is how to calculate your daily calorie needs so you can adjust your diet to suit your body's requirements.
Thus, you can maintain your ideal weight, meet your daily energy needs, and live a healthier and more balanced lifestyle.
