Calories – we most worry about
When we refer the calories in food, what do we mean? A calorie is a unit of measurement — but it doesn’t measure weight or length. A calorie is a unit of energy. When you hear something contains 100 calories, it’s a way of describing how much energy your body could get from eating or drinking it.
All food items have a a set energy value which determines the amount of energy it can give us once consumed. The more active your lifestyle is the higher your energy needs are going to be.
The energy all food contains is usually measured in Calories (with a represented as C) which is short for kilocalories. 1 Kilocalorie = 1000 calories (small c) = 1 Calorie (capital C).
What is one Calorie? It’s a measure of energy. A calorie is a unit that is used to measure energy. The Calorie you see on a food package is actually a kilocalorie or 1,000 calories. A Calorie (kcal) is the amount of energy needed to raise the temperature of 1 kilogram of water 1 degree Celsius. Sometimes the energy content of food is expressed in kilojoules (KJ), a metric unit. One kcal equals 4.184 kj. So the Calorie on a food package is 1,000 times larger than the calorie used in chemistry and physics.
How Calorie of food is is determined? The Calorie level placed on a packaged food can be calculated from food components. Most of the calorie values on industry food tables are based on an indirect calorie estimation made using the so-called Atwater system. In this system, calories are not determined directly by burning the foods. Instead, the total caloric value is calculated by adding up the calories provided by the energy-containing nutrients: protein, carbohydrate, fat and alcohol. Since carbohydrates contain some fiber that is not digested and utilized by the body, the fiber component is usually subtracted from the total carbohydrate before calculating the calories.
The Atwater system uses the average values of 4 Kcal/g for protein, 4 Kcal/g for carbohydrate, and 9 Kcal/g for fat. Alcohol is calculated at 7 Kcal/g. (These numbers were originally determined by burning and then averaging.) Thus the label on an energy bar that contains 10 g of protein, 20 g of carbohydrate and 9 g of fat would read 201 kcals or Calories.
In order for body to process food it has to go through the processing cycle and this processing requires energy that is subtracted from the food itself. Roughly 10% of the total energy value consumed will be used up in order to metabolize it but different types of food will be processed differently due to different cellular structure and use up more or less energy. The list below gives you an idea of the percentage of a food’s intake that goes into processing it fully:
Protein: 20% to 35% of the energy consumed
Carbohydrates: 10% to 15% of the energy consumed
Fats: at most 5% to 15 % of the energy consumed
These values may vary based on various factors but in nutshell when we count our calorie intake then we must allow ourselves a margin of error.
Not all the energy is available to us right away after eating, this is because different food types require different levels of enery to digest, for example protein takes longer to digest the energy is released slower keeping us fuller longer. Carbs, on the other hand are digested faster as they serve as main source of energy and very little are wasted in the process and they release instant energy to be used right away, which is why we love eating a bread or a bar of chocolate before a long run.
When our body doesn’t need to spend energy, that energy is reserved for later use, thus it goes into the fat cells. Any energy that is not wasted is kept by the body no matter where that energy came from – protein, carbs or fat. That’s why it is preferable to eat less meat and more vegetables and fruits. Meat will keep you full for a while whereas you will still be hungry in 30 minutes after you have eaten a plate full of fruits.
Thus, the conclusion is, it can be stressful and it can take the joy out of every meal if you count every calorie. Eating should ideally be mindful and we must control portion intake. There is a reason we opt for healthier whole foods and stick to high protein eating patterns – because no one enjoys misery and certainly no one can stick to it long-term. The more protein you have in your diet the fuller you will feel and as a result you are less likely to add a snack. Eat local and eat home cooked food, that is the mantra I follow.