“Calories” is a familiar word in food nutrition labels, but what it actually is might be unclear to some, and sometimes, vague ideas that calories are bad also abound. There is an importance in understanding calories, because they play a huge factor in one’s health.
What are calories? Calories are vital units of heat energy. They fuel the body the same way cars are
fueled by gasoline. Calories come from the food consumed, as they also refer to the amount of energy stored in foods. However, energy and calorie amounts vary depending on what is eaten; this is why different foods have different numbers of calories.
There are three main sources of calories that contain different amounts of energy per gram:
There is also a general reference for calories in a single serving of food. Low-calorie food contains 40 calories or less. Moderate-calorie ones at least have 100 calories while high-calorie foods have 400 or more.
Checking the calorie section of a label can help consumers manage the recommended calorie intake for nutrients. Most foodstuffs include a calorie label or nutrition facts panel on their packages. The label indicates the number of calories per serving along with the portion size per serving, so the servings one consumes determines the amount of calories taken (portion amount).
For example, if a bag of potato chips is said to have about 270 calories, and there are 27 chips, this means that each chip has about 10 calories.
Another example: if the food label indicates that the item contains 250 calories per serving, and the calories from fat are listed at 110, then more than half of the calories came from fat. If the package has two servings and a person consumes it whole, then the total number of calories would double. This shows that serving size is important in calculating calories.
The function and importance of calories in the body
In general, the amount of calories people take in, as well as its source, can make an impact on their overall health since calories have the following functions in the body:
Calories provide energy for humans to do their everyday routine, as well as to maintain basic life support functions such as breathing, repairing cells, circulating blood, and other bodily functions. Energy is even needed while at rest. Having enough food ensures that the body has efficient energy to function and develop properly.
As people consume food, their digestive system undergoes metabolism, the process by which the body converts the calories from food into energy. Metabolism and needed calories are determined by factors such as gender, age, and physical activity habits.
The amount of calories taken in is one of the factors that determine if a person gains, loses, or maintains weight. Consuming the correct amount of calories per day maintains weight, while having too much calorie consumption can lead to weight gain.
Checking a food’s nutrition label can help determine how many calories one is taking in per day.
How many calories does a person need?
The answer varies depending on factors such as age, gender, height, weight, and physical activities. There are online calorie calculators that can help; however, these calculators might not always be accurate.
In relation to this question, it is important to know one’s basal metabolic rate (BMR). BMR is the amount of calories a person burns when he or she is not doing anything, without having to eat for the last 12 hours. Basically it is the minimum calories the body needs to keep the organs running. There are online BMR calculators available.
However, BMR is just an estimation and may not be accurate for everyone. The BMR estimates also do not consider the amount of body fats or muscles of a person.
After finding out the BMR, the next step is to figure out the Total Daily Energy Expenditure (TDEE). It is the amount of extra calories people use every day based on their physical activities. There are online calculators for this as well. These can help a person determine the number of calories he or she needs.