Is a Calorie a Calorie?
Over the past few weeks there has been a constant stream of news stories all focusing on the amount of sugar in our diet. Stories ranged from monkeys being banned from consuming bananas as these are too high in sugar, through to an expert committee being set up in the UK to try and cut the amount of hidden sugars in our diet. Whilst this is all positive news we here at Natural Ketosis welcome, there is unfortunately still some disagreement regarding the issue of either reducing the amount of sugar in items, or simply reduce the overall number of calories in products.
The term calorie is used both in physics and nutrition where in both cases it is a measure of energy. The nutrition calorie is based on the physics calorie whereby it is the amount of energy needed to increase the temperature of 1 kilogram of water by 1o Celsius (Kcal). Whilst in an abstract world this form of energy conversion is quite straightforward, it gets quite more complicated when this notion of energy conversion is applied to complex beings such as humans.
In the food manufacturing business, the food used to be placed in a sealed container surrounded by water. The food was then burned completely to raise the water temperature thus resulting in the amount of calories (energy) available in the food. Nowadays however this is no longer done. The total calorie amount of a processed food is determined by taking the individual calorie content of the ingredients and added together .
In animal biology, when researchers are the studying calorie intake of animals, the only way to clearly ascertain energy intake and usage is to weigh the food prior to consumption and then weigh and analyse the contents of the animals’ excretion. It is for this very reason that when calories are used to determine energy intake from a human perspective, the concept is wrong and misguided .
The way an individual makes use of the calorific energy found in food varies from person to person and is dependent on a number of things such as type of food eaten as well as type of bacteria present in the gut. Processed foods are very easily digested and do not require a lot of effort whilst green vegetables, nuts and meat require a lot more energy to be properly digested and generally provide much better amounts of vitamins, minerals and nutrients, both for your body but also for your gut bacteria .
The human digestion process is an intricate mechanism, one which can not be simplified to mere calories in and calories out.
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