Counting Calories Part 1
Understanding how to work out calories

In the quest for a better body most people will sooner or later cross paths with counting calories in their diet. Here are some basics surrounding the concept that will help you better understand what this is all about.

All out food is made up of various components, but the three we are mostly interested in is the Protein, carbohydrate and fat content. The reason for this is that these are the only ones that have a nutrient or caloric value. If you take a fruit for instance, it is made up of mostly water and fibre and fruit sugars. The sugar component is the one that you have to count when you are dieting by the numbers.

This essentially means that you have to know what the breakdown of nutrients is in the food you are eating. This is mostly found on the label of nutritional values on the packaging, but there are also various generic values for things like red meat, vegetables and so on. The first thing to understand is that most often these values are based on 100g of the substance, but sometimes they are nice enough to give you the serving size. In the case of say vegetables you have to weight the actual food to be able to work out the calorie value.

Example: (values are not real)
On one of the values charts you’ll find that potatoes have a calorie breakdown of the following per 100g:

Protein: 0g
Carbohydrates: 50g
Fat: 0g

This simply means that for every 100g of potatoes, you’ll have 50g of carbohydrates. You can work out the same for protein and fats if they where present. This is the first step. Now it becomes more interesting. In the case of protein and Carbohydrates, each gram represents 4 calories. (There are some arguments about this as some people say 3 and some 4 anyway I stick to 4.) For the example above you’ll find that means there is 4 x 50g = 200 calories for each 100g of potatoes you eat. If there was protein you can work that out as well.

In the case of fats, the calorie yield is much higher at 9 calories per 1g of fat. To get the total calorie value of the food you are eating you would have to work out the amount or serving you are eating. To do this you need the actual weight of your portion. If we use the following example:
The chart list the food values per 100g as:

Protein: 15g
Carbohydrates: 25g
Fat: 2.5g

Your portion is 45g and you now have to convert this to calorie value. Firstly you need to apply the values to the amount you are consuming 45g. To do this you need to factor the values with the weight of the food. Basically this means you divide the values with 100 because they where for 100gs and this will turn them into a percentage you can then apply to the weight of your portion. This mean that the gram value for protein for your serving will be 15g/100 = 0.15. And by multiplying this factor with your serving weight: 45g x 0.15 = 6.75g of protein in 45g of food you ate. You can do the same for Carbohydrates and you should get a value of 11.25g and for fats it will be 2.5/100 = 0.025 x 45g = 1.125g of fat.

The next step here is to work out the calorie value. With Protein and Carbohydrates it is simple because you can add the gram values together and multiply by 4. This means 6.75g of protein and 11.25granms of carbohydrates for a total of 18g, this multiplies by 4 gives us 72 calories. Now we need to add the fat calories. This is done by taking the fat value in grams of 1.125 and multiplying by 9 for a total of 10.125 calories. Finally we add the values together to get the total caloric value; 10.125 + 72 = 82.125
calories per 45g serving.

The breakdown for calories then:
Protein: 27 calories
Carbohydrates: 45 calories
Fats: 10.125
Total calories: 82.125 calories per 45grams

For some people this will be fine but for most people on a diet you need to take this a step further and work out percentages. This is where people make a major mistake sometimes. Often what happen is that people work out the percentage in grams of each one of the food components? This is a mistake because you really want to work out the percentage of calories to get to the real figures you want. If you worked out according to weight you would get the following values; for protein it would look like 11.25g/45g x 100 for percentage = 25% of total, for carbs it would look like 55.5% and for fats 5.5%.

This means that the food look like it as 5.5% fat and this is often what manufacturers use to tell you their food is low in fat. What is the real fat here? What is real that as a percentage of weight per substance in your food these figures are correct, but what happens when you display them as a nutritional value of the same portion of food? Lets see;

For protein the figure would be worked out as follows; the total caloric value is 27 calories, so for protein calories would be 27/82.125 x 100 = 32.87% of overall caloric value. Carbs are then in the same way comes to; 45/82.125 x 100 = 54.7% and for fat it would be 10.125/82.125 x 100 = 12.32%. Now lets paint the real picture about nutritional value of the food;

The serving has 12.32% of fat for a nutritional point of view and this is nowhere near as good looking on paper as the 5.5% on the label. I hope you can see how clever marketing figures can be, but don’t be fooled by it!