How many calories do our bodies need? Is it necessary to count them?
In the daily diet or when resorting to a weight loss diet, the typical question usually arises: how many calories do you need per day? So let's see how to determine the quantity needed.
It should be noted that current nutritional trends downplay the importance of counting total calories. Instead they focus on other metrics like metabolic health or food combinations.
Basal metabolic rate and calories as a unit of measurement
To begin, we must first understand the principle of basal metabolism or TMB. This concept refers to the amount of calories the body burns, even at rest.
A calorie is the amount of heat needed to raise the temperature of a liter of water by one degree at normal atmospheric pressure. In reality, it is a disused unit of energy within the system of units of measurement. Its use today is reserved for the field of nutrition, where it allows us to express the energetic power of food.
In nutrition, what we actually count are kilocalories - 1 kcal = 1000 calories - although they are commonly referred to as calories.
Counting the kilocalories of a food allows us to know how much energy we have ingested and if this will be enough to keep us alive.
The energy that living beings need to live is obtained from the macronutrients provided by food, although it must be taken into account that each food provides different quantities.
The body uses its energy, in the form of kilocalories, to warm up, to keep itself alive and also to carry out physical or mental activity. The sum of all these expenditures equals the total energy demand.
How are calories used?
The energy that the body needs during the day is used in the following aspects:
Basal metabolism
It refers to the minimum calorie consumption that a living organism needs to complete its basic vital activities. It can be estimated using the Harris Benedict formula, according to a study published in Clinical Nutrition, which takes into account data such as weight, gender and age.
Cell growth and renewal
Cell regeneration, like the creation and renewal of tissues, requires energy to be produced properly.
Physical activity
It is the consumption of calories necessary to carry out the different activities and is classified into minimal, moderate and intense activity.
Stressful situations
Like a disease or surgery. Even the stress itself, in the central nervous system, may affect energy expenditure.
How many calories do our bodies need every day?
To have a good energy balance and not lose or gain weight, we must introduce the same calories we consume every day. This way we will have the energy needed to sleep, digest, circulate blood in the arteries or breathe.
With food we give the body the amount of calories it needs to function properly, through the right amount of carbohydrates, proteins , fats and water, which are present in the different foods we consume every day.
It is very important to note that although a standard number of calories is often suggested for adults, these are determined by many factors. Needs may vary based on:
- Sex
- Age.
- Daily activities.
To find out how many calories our body needs per day, we first need to calculate our basal metabolic rate. This represents about 60% - 70% of the total calories that the body spends on a daily basis and which, therefore, we must provide for it to live and enjoy good health.
Calculation of basal metabolic rate
As mentioned, several factors are considered to calculate the basal metabolic rate such as:
- Sex
- Age.
- Height.
- Weight.
Although there are several formulas for obtaining this value, a very reliable and precise equation has been established by Harris Benedict. According to an article published in Clinical Nutrition ESPEN , it has the following formula:
Men: TMB = (10 x weight in kg) + (6.25 x height in cm) - (5 x age in years) +5
Women: TMB = (10 x weight in kg) + (6.25 x height in cm) - (5 x age in years) - 161
Since this rate only shows us the minimum consumption of the body at rest, it is now necessary to calculate the energy expenditure based on the lifestyle. This is because the expenditure of a person who spends eight hours sitting in the office will not be the same as that of an athlete who trains two hours a day.
A quick and easy way to calculate the daily calories you need is to multiply your weight by 15. This will give you the number of calories needed to maintain your current weight.
It's not just calories that count
Although many experts still focus on calculating calories in weight loss diets, the truth is that without this method, good results can be achieved.
It should be noted that it will be essential to propose a good combination of foods, along with practicing physical exercise on a regular basis. The latter has proven to be one of the best tools for improving body composition and solving metabolic inefficiencies .
Calories have been and are the units by which the energy needed and consumed by the body is measured. They allow you to make an estimate of the subject's needs, although this estimate is not a precise calculation. In short, calories are useful for planning adequate diets, but they are not the only factor to consider.
