Calories
All food and beverages have energy sealed in chemical bonds. When the drink or food is ingested, the body breaks down or metabolises it to release the accumulated energy.
The cells in the body then capture and utilise the released energy to fuel normal bodily functions required for survival. We use a unit known as a calorie to calculate the energy extracted and used from foods and drinks. To put it differently, a calorie is a basic measurement unit of energy.
Almost everything we eat has a calorie count, and those calories are attributed to three energy sources: carbohydrates, proteins and fats.
- Carbohydrates: 4 calories per gram
- Protein: 4 calories per gram
- Fats: 9 calories per gram
Carbohydrates
When you consume carbohydrates, the digestive tract breaks them into a sugar called glucose. Glucose is the fundamental fuel source for your brain, nervous system and red blood cells.
Carbohydrates can be classified into simple and complex depending on the number of sugar molecules they have. Simple carbohydrates, such as table sugar and fruit juice, can be broken down easily and used as energy; however, they can also cause a swift rise in blood sugar.
Simple carbs are also found in whole fruits because they are filled with dietary fibre, and the sugars are broken down slowly.
Complex carbohydrates are present in unrefined whole grains, vegetables and legumes. They are also broken down more slowly, giving long-lasting energy. For one gram of carbohydrate consumed, four kcal of energy is produced.
Fats
Dietary fats play an important role in safeguarding vital organs, producing harmones, insulating the body and assisting the body absorb vitamins A,D,E and K. They can also be broken down and utilised as a source of energy.
Even though carbohydrates are the body's favourable energy source, fats are more snugly packed and store bigger amounts of energy in less space.
Proteins
Even though energy can be acquired from protein, the body chooses to use this macronutrient to repair tissues, create enzymes, synthesise immune-protective antibodies, balance pH, produce hormones and transport nutrients in and out of your cells.
The protein is rarely used as an energy source. In order to save protein for its primary functions, fats and carbohydrates are utilised as fuel at first hand. Hence, consuming sufficient amounts of carbohydrates and fats is important to prevent extra protein from being converted into energy.
Nevertheless, if the body is not getting an adequate supply of calories from carbohydrates and fats, protein can be broken down to give 4 kcal per gram consumed. Protein-rich foods consist of dairy, meat, eggs, legumes, seeds and nuts.
How many calories do you need?
The total number of calories an adult aged 19 to 59 needs daily ranges from 1,600 to 3,000 kcal. Particularly, adult females need about 1,600 to 2,400 kcal per day, while adult males require around 2,000 to 3,000 kcal per day.
With respect to the calories consumed, 20% to 35% from fats, 45% to 65% must come from carbohydrates, and 10% to 35% from protein. To calculate your personalised caloric needs, it is vital to consider the following factors.
Fundamental Metabolic Functions
Your body needs a minimum number of calories to execute the essential metabolic functions that continue life. These fundamental functions include respiration, cell production, circulation, nutrient processing, protein synthesis and ion transport.
The minimum number of calories required to fuel these activities is called the basal metabolic rate (BMR). It represents 60% to 75% of the body's total energy expenditure.
Various factors influence BMR, such as age, weight, height, body temperature, body composition, climate, sex and hormone status. Thus, each individual's caloric needs are specific.
Exercises
Another main component of energy expenditure is exercise. Caloric requirements differ depending on the type, frequency, duration and intensity of physical activity.
For individuals who make exercise as a habit, energy requirements must be adequate to fuel and manage muscle mass. People with higher amounts of muscle mass are inclined to burn calories more quickly.
Conversely, people who are physically less active and have less muscle mass burn calories slowly. Henceforth, strength training exercises may assist in increasing the rate at which calories are burned.
Calorie vs. Nutrient Dense
A food or beverage is calorie-dense when it contains a high number of calories per serving, and some of these foods have few nutrients. These types of foods are often high in saturated fat, added sugars and sodium. Examples of calorically dense, nutrient-poor foods include cakes, candy, pastries, sugary drinks, fried food and highly processed meats.
On the contrary, nutrient-dense foods have high levels of nutrients, like minerals, vitamins, fibre, and phytochemicals, and sometimes have fewer calories. Nutrient-rich foods include vegetables, fruits, whole grains, nuts, legumes, seeds, dairy products, fish and unprocessed lean meat. These foods give fundamental nutritional components for good health.
The important part of creating a well-balanced diet is picking nutrient-dense foods and reducing calorie-dense foods that are also less nutritious within your caloric needs.
Link Between Calories and Body Weight
Although there are multiple factors to consider for weight management, calorie intake plays a major role. To manage a stable body weight, the amount of calories you take in must be equal to those you expend through fundamental metabolic functions and exercise. Nevertheless, if you like to gain or lose weight, these are things you should keep in mind.
Weight Gain
When your caloric intake is constantly higher than the number of calories you burn, you step into a calorie surplus and experience weight gain. If weight gain is your aim, not only is it required to consume more calories, but you should also consider weight training to raise your body mass in muscle.
To accomplish your daily caloric target, it may assist you in consuming five to six meals spread out throughout the day. It is also important to prioritise high-calorie foods that are also rich in nutrients to ensure your weight gain happens in a healthy way.
Summary
Calories are frequently associated with weight gain and obesity, but they are essential for health. Consuming more than the suggested amount may pose a health risk.
