Calculation of daily calorie/energy needs and expenditure (TDEE calculator)

What is my daily energy consumption and calorie intake requirement?

What is your approximate calorie intake requirement for one day? Total energy expenditure is informative for most people.

In some situations, it is useful to know this number. Probably everyone has encountered it during their lifetime.

How do you calculate your daily calorie intake?
Total Daily Energy Expenditure (TDEE) - Total Daily Energy Expenditure / Total Daily Energy Expenditure (CDEV)

What are the circumstances? When do I need to know this number?

There are three situations:

1. You need to lose weight
2. you want to gain weight
3. You want to maintain your current body weight

Sometimes it is simply good to know your approximate energy needs and consumption during a day.

The energy balance is influenced by 4 factors.

Factor number 1 = Basal Metabolic Rate (BM)

Our body has a basal energy consumption called basal metabolism (BM).

The human body consumes energy even when we are doing absolutely nothing, sleeping, not thinking. This is due to life processes and functions, cell metabolism, body metabolism, food digestion, nervous system functionality, brain, heart function, breathing and so on.

Basal metabolic rate - abbreviated BMR (Basal Metabolic Rate).

Basal metabolic rate consumes most of the daily energy = 45-70% of energy needs depending on the situation.

What influences the basal metabolic rate?

Factors affecting BMR:

• Body weight and ratio of muscle mass without fat - The body itself and its proportions. Muscles use more energy even at rest.
• Fat mass and body fat ratio - Fat mass has a lower energy requirement than muscle. The more of it there is, the calorie requirement goes up.
• Age - Higher BMR in childhood and during growth. At older ages, metabolism usually slows down.
• Gender - Men have more muscle mass.
• Genetics - The genetic makeup is different for each person.
• Body temperature - Increased body temperature or fever increases energy requirements.
• Environmental temperature - At higher or lower temperatures, the body has more work to do to maintain the correct body temperature.
• Hormones - Their production and hormonal activity.
• In pregnant women - The fetus has its own energy needs.
• Activity level - Due to recovery after a hard workout.

2. Working metabolism

Second only to the basal vital energy requirement is the need to supply the body with energy for work. This includes travel to and from work, sporting activities and other daily activities.

Professionally, this is the so-called work metabolism.

It is our responsibility to supply the body with enough energy to cover the energy needs and consumption during the day at work.

Factors 3 and 4 = food and digestion

In addition to basal and working metabolism, we must also take into account the so-called specific-dynamic effect of food (factor number 3).

It expresses the energy consumption in relation to the energy obtained from food.

Even the digestion of food (factor 4) is an activity. Therefore, sufficient energy must be supplied for it.

To recap...
Catabolism = the release of energy in the breakdown of substances.
Anabolism = the consumption of energy for the synthesis and formation of substances.

The predominant type of food plays a role in digestion and energy production. More energy is used in processing proteins than in breaking down sugars.

More information to understand the calculator/formula

These 4 factors together influence daily energy requirements.

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Energy requirements change with age. Each person is different and has different needs.

Approximate energy requirements by age are given in the table - 1 kJ/kcal per 1 kg of body weight

Looking at the table we can calculate for example:

• adult male
  • 80 kg and an energy requirement of 130 kJ per kg
  • 80 x 130 = 10400 kJ / 2485 kcal
• 12 year old boy
  • energy requirement 270 kJ and 40 kg
  • 40 x 270 = 10800 kJ / 2581 kcal

What next with this information?

It depends on what you want to achieve. As we have already mentioned...

You want to maintain your current body weight?

If your goal is to lose weight, you should maintain a slight caloric deficit = negative energy intake.

For appropriate weight loss, you should reduce your energy intake by approximately 500 calories per day.

If you want to gain weight, you should increase your caloric intake and be in a caloric surplus = positive energy intake.

Weight gain will provide an increase in daily energy intake of about 250-500 kcal per day.

Good to know:

• Protein has approximately 4.1 kcal/17.1 kJ per 1 g.
• Sugars have approximately 4.1 kcal/17.1 kJ per 1 g.
• Fats have approximately 9.3 kcal/38.9 kJ per 1 g.

Breakdown of daily diet and energy coverage for essential nutrients:

• Protein 10-15 %.
• This corresponds to about 50-70 grams per day for an adult
• of plant and animal origin
• Carbohydrates about 50-65%
• 300-500 grams per 1 day for an adult
• refined sugar should be less than 10%
• fibre is important and the daily intake should be 20-30 grams
• Fats approximately 25-30 %
• together this is about 50-80 grams for an adult
• a higher proportion of unsaturated, healthy fats is advisable

It is important to follow the principles of a sensible, rational and varied, balanced diet. This is the only way we are able to meet the needs of the body and metabolism. It is important to provide the body with the necessary vitamins, minerals and trace elements.

Drinking is also important.

The calculator with the attached formula for calculating your approximate daily energy requirements will help you reach your goal.

Calculating daily calorie intake

To get an approximate estimate of your daily energy needs, we need two numbers.

1. Basal metabolic rate

2. Activity estimation factor.

Please note:
BMR, activity coefficient and resulting daily calorie consumption provide only approximate numbers. They are not an exact result and mirror the real situation.

The formula for calculating calories needed per day:

BMR x Activity Estimation Factor = Result in kcal per day

Table: BMR for men and women (+ formulas)

x

Physical activity estimation coefficient - table

Examples of balanced energy intake = maintaining current body weight:

• A man, 30 years old, 190 cm and 90 kg should take in approximately 3,011 kcal during moderate activity.
• Female, 30 years, 170 cm and 60 kg should take in approximately 2095 kcal at moderate activity.

The calculation is of course only informative. It does not take into account the differences and peculiarities of each of us.

We should not forget the differences of each day.
We do not perform the same activity and do not have the same mental or physical load.
Every day is different.

But for a rough idea, this is enough.

For more information and calculations you will need the advice of an expert.

Other useful calculators:

• BMR - Basal Metabolic Rate Calculator
• Calculator: How to convert kJ and kcal?

For more information, visit our articles:

• What are proteins, sugars, fats?
• Metabolism: What is it, what are its functions and how to support it?
• How does protein benefit skin health + What does protein contain?
• What are amino acids and why do they need to be added to the body?
• Carbohydrates: division and function in the body + Sources and content of carbohydrates in the diet
• How to lose weight at home and in a healthy way? Appropriate diet, exercise and nutritional supplements
• How to prevent cardiovascular disease?
• Do you know metabolic syndrome and its complications?