A calorie is a unit of energy. In nutrition, calories refer to the energy that people get from the food and beverages they consume, and the energy they use in physical activity.
Knowing the calorie content of food and drink can help ensure that you are not consuming too many calories.
The calorie content of many store-bought foods is listed on the packaging as part of the nutrition label.
What is a calorie?
The calorie (symbol cal) is a unit of energy of the now disused Technical System of Units, based on the specific heat of water. Although in current scientific use, the unit of energy is the joule (from the International System of Units), the use of calories remains to express the energy power of food.
The calorie was defined for the first time by Professor Nicolas Clément in 1824 as a calorie-kilogram and was thus introduced in the French and English dictionaries during the period between 1842 and 1867.
The calorie is defined as the amount of heat energy required to raise the temperature of a gram of pure water by one degree Celsius, from 14.5 ° C to 15.5 ° C, at the normal pressure of one atmosphere. A calorie (cal) is exactly 4.1868 joules (J), while a kilocalorie (kcal) is exactly 4.1868 kilojoules (kJ).
The importance of calories
The notion of calorie is important to explain the functioning of the food process. Living beings need energy to survive; This energy is obtained from food. Food, therefore, is the most relevant source of energy for living organisms.
The energy obtained from the nutrients found in food is converted into calories or, more precisely, into kilocalories (that is, thousands of calories). The body uses calories in diseases, stress situations and metabolic processes.
Calories and nutritional properties of food.
The number of calories present in a food must be specified on its label. This amount is responsible for informing what the energy value of the food is and is very important both to maintain the ideal weight and figure, and to try to recover them. When preparing a dish, it is essential to know how to differentiate between the different types of ingredients, use the appropriate proportion of each one and choose the best cooking mode.
Understanding the nutritional properties of food is essential to steer our diet in a healthy direction and to make this become a lifestyle and not a mere passing practice. To understand each of the values indicated on packages, jars and wrappers it is highly advisable to ask a nutritionist for help.
Many times, due to lack of information and tools to understand the energy value of foods, they are misjudged and more calories are ingested than expected. A clear example is avoiding eating a chocolate cookie and replacing it with twenty cereals.
It is very important to know the distribution of the so-called macro nutrients in each food and the number of calories per gram they provide: carbohydrates and proteins, 4; fats, 9; and alcohol, 7. To facilitate the comparison of the caloric content of various products, it is always calculated based on 100 grams of the food in question.
The more water a food contains, the less energy it provides; in the case of vegetables, for example, almost 95% of their weight is wet. On the contrary, products such as bread and nuts have a high energy value, given the small proportion of liquid present in their composition. Fats, on the other hand, are the nutrients that add the most calories; This is the case of oils, butter and margarine, among others.
How to calculate the calories you eat
How many calories should you eat to maintain your weight? Here's a trick to figure out how many calories you should eat to maintain your weight.
Ideal weight (in kg) x 30 = Calories
Get your ideal weight and multiply it x 30. This should be the number of calories you can eat in a day. Of course, this is not very accurate, as it does not involve important factors such as lifestyle and gender.
Factors that influence the number of calories you should eat:
· Male Female.
· Active / sedentary lifestyle.
The United States Department of Health and Human Services recommends the following numbers:
Sedentary lifestyle (less than 30 minutes of moderate physical activity / day)
· Men 18-30 years: 2400 calories
· Women 18-30: 2000 calories
· Men 31-50: 2,200 calories
· Women 31-50: 1800 calories
· Male 50+: 2,000 calories
· Woman 50+: 1600 calories
More active lifestyle (more than 30 minutes of moderate physical activity / day)
· Men 18-30 years: 2600-3000 calories
· Women 18-30: 2000-2400 calories
· Men 31-50: 2400-3000 calories
· Women 31-50: 2000-2200 calories
· Male 50+: 1800-2200 calories
· 50+ Woman: 2200-2800 calories
These numbers will maintain your current weight
To lose weight, you must increase physical activity and reduce calorie consumption. Try to eat 400 calories less than what you are used to and soon you will start to lose weight. It is always advisable to consult a nutrition specialist to control your weight loss saludbale.