A calorie is a unit of measurement for energy.
Technically saying one gram calorie equal to the energy needed to increase the temperature of 1 gram
of water by 1 °C and One kilogram calorie equal to the energy needed to increase the temperature of 1
kg of water by 1 °C and this is equal to 1000 calories.
However when we are discussing the word calorie in food and nutrition terms, nutritional calories
are not measured amounts of energy, but are calculated from food composition.
Nutrient Calories per gram
Carbohydrate 4 kcal
Protein 4 kcal
Fat 9 kcal
Alcohol 7 kcal
1 kg of body-fat tissue has roughly the caloric energy of 870 g of pure fat, or 7800 kcal.
In theory one has to create a 7800 kcal deficit to lose 1 kg of body-fat.
Our bodies use the energy found in the food we eat to keep us moving and store any excess energy as
body fat for future use.
When we spend the more energy or when we are burn more calories than we eat, then our bodies look
forward towards our fat stores in our body to find the additional energy they require.
So for simple understanding when we eat more calories than we need or spend, we gain weight, and
when we burn more calories than we eat we lose weight.
A pound of body fat equal to approximately 3500 calories. So if you have a calorie deficit of 500 calories
each day you would lose approximately one pound per week: 500 x 7 = 3,500