What are calories?

The nutritional information on all food packaging will advise how many calories it contains.

Most people only associate calories with food and drink, but anything that contains energy has calories. 1 kilogram (kg) of coal, for example, contains 7,000,000 calories.

There are two types of calorie:

  • A small calorie (cal) is the amount of energy required to raise the temperature of 1 gram (g) of water by 1º Celsius (º C).
  • A large calorie (kcal) is the amount of energy required to raise 1 kilogram (kg) of water by 1º C. It is also known as a kilocalorie.

1 kcal is equal to 1,000 cal.

The terms "large calorie" and "small calorie" are often used interchangeably. This is misleading. The calorie content described on food labels refers to kilocalories. A 250-calorie chocolate bar actually contains 250,000 calories.

Daily requirement

Research as shown that the average man needs 2,700 kcal per day and the average woman needs 2,200 kcal per day.

Not everybody needs the same number of calories each day. People have different metabolisms that burn energy at different rates, and some people have more active lifestyles than others.

The recommended intake of calories per day depends on several factors, including:

  • overall general health
  • physical activity demands
  • sex
  • weight
  • height
  • body shape

Calories and health

The human body needs calories to survive. Without energy, the cells in the body would die, the heart and lungs would stop, and the organs would not be able to carry out the basic processes needed for living. People absorb this energy from food and drink.

If people consumed only the number of calories needed every day, they would probably have healthy lives. Calorie consumption that is too low or too high will eventually lead to health problems.

The number of calories in food tells us how much potential energy they contain. It is not only calories that are important, but also the substance from which the calories are taken.

Below are the calorific values of three main components of food:

  • 1 g of carbohydrates contains 4 kcal
  • 1 g of protein contains 4 kcal
  • 1 g of fat contains 9 kcal

As an example, here is the breakdown of how a person would get calories from one cup of large eggs, weighing 243 g:

Fat: 23.11 g

23.11 g x 9 kcal = 207.99 kcal

Protein: 30.52 g

30.52 x 4 kcal = 122.08 kcal

Carbohydrate: 1.75 g

1.75 x 4 kcal = 7 kcal

243 g of raw egg contains 347 kcal. 208 kcal comes from fat, 122 kcal is taken from protein, and carbohydrate provides 7 kcal.

Empty calories

Empty calories are those that provide energy but very little nutritional value. The parts of food that provide empty calories contain virtually no dietary fiber, amino acids, antioxidants, dietary minerals, or vitamins.

According to ChooseMyPlate.gov, a diet management tool from the USDA, empty calories come mainly from solid fats and added sugars.

  • Solid fats: Although these exist naturally in many foods, they are often added during industrial food processing, as well as during the preparation of certain foods. Butter is an example of a solid fat.
  • Added sugars: These are sweeteners that are added to foods and beverages during industrial processing. They are filled with calories. In the U.S., the most common types of added sugars are sucrose and high-fructose corn syrup.

Added sugars and solid fats are said to make foods and drinks more enjoyable. However, they also add many calories and are major contributors to obesity.

Alcohol can also contribute empty calories to the diet. One normal serving of beer can add 153 kcal to a person's intake for the day.

If beer is not your drink of choice, you can use this calorie calculator provided by the National Institute on Alcohol Abuse and Alcoholism to work out how many calories alcohol adds to your diet.

Sources of empty calories

The following foods and drinks provide the largest amounts of empty calories:

Solid fats and added sugars

  • ice cream
  • donuts
  • pastries
  • cookies
  • cakes

Solid fats

  • ribs
  • bacon
  • hot dogs
  • sausages
  • cheese
  • pizza

Added sugars

  • fruit drinks
  • sports drinks
  • energy drinks
  • soda

Summary

What should i be eating when it comes to losing or putting on weight? Losing weight requires a clean source of protein,carbs & fats within a calorie content lower then your daily requirement. This does not mean starve your self and infact means you need to eat clean meals more reguarly ( usually 4-6 meals a day ) this will in return help speed your metabolism. If your daily calorie intake requirment is approx 2,000cals then start by lowering your calories by 100-200calories with each week being monitered.

I am looking to put on Weight but don't know how? You will need to eat more then your daily requirement. For example if your daily requirement is 2,000 calories then you will need to put more then this by increasing your food intake. Try and keep it clean as you do not want to resort to sugary treats. Increasing Carbohydrates is the easiest way i.e Sweet potato, Rice etc. Protein shakes is also a easy way to gain extra calories. Try increasing by 200calories, slowly increasing weekly.

 

INDEX: some of the content and research is by medicalnewstoday.com