Foods have a different caloric density made up from a combination of carbohydrates, protein and fats. Exactly how many calories are present in each food or product will depend on several factors. Generally, processed or convenient foods contain more calories than their natural counterparts. This is usually because food manufacturers add extra sugar and/or fats to enhance the taste, or they use a certain cooking technique that adds extra oils to the overall product.
As an example, a pasta bake ready-meal will usually have a higher caloric content than the same meal prepared at home using dry pasta and the same basic ingredients. For a cooking example, vegetables roasted in a little oil will always contain more calories than the same vegetables prepared by steaming or boiling. Many tinned products are the same, a canned vegetable stew will often contain higher calorie values than the same recipe of vegetable stew that has been prepared at home and using the same cooking methods.
The same recipe can also differ in the energy value if there’s a different proportion of ingredients used. For example, if a meat pie has a higher percentage of meat than a cheaper version of the same pie, then it will probably contain a greater energy content. This is because most red meats are high in fat and calories. So buying the most expensive food products may not be the best choice when trying to reduce calorie intake to lose weight. It may be best to try and balance the cost to energy content by comparing the choices.
All foods have a unique combination of macronutrients, carbohydrates, proteins and fats. The proportion of these nutrients present in each food will produce a certain level of energy. Many items that are considered high-fat foods such as hard cheese, double cream, nuts, chocolate and many red meats tend to have a high calorie level. This is because fat contains more than double the energy content of either protein or carbohydrates. Looking at the chart below you can see the different energy content per gram for each of the basic macronutrients.
Basic Energy Value for each Macronutrient (per gram):
- Carbohydrates: 4 calories per gram
- Protein: 4 calories per gram
- Fat: 9 calories per gram
- Alcohol: 7 calories per gram
Many foods that are considered a carbohydrate source, such as fruit, vegetables and natural grains, tend to be lower in energy content. This is because carbohydrates only contain 4 calories per gram, plus their sugar content is naturally lower than many common foods. However, modern food products that are predominantly carbohydrate sources now have a lot more sugar added, often to improve the taste, and unfortunately this has pushed up their energy content from low calories to medium. Some are even categorized as a high calorie food after much processing.
Energy in alcoholic drinks
The most obvious point to consider with the calorie values of drinks is their sugar levels. Many soft drinks like sodas tend to have extra calories from the large amounts of sugar added to the drink. It is also very easy to ingested lots of these empty calories during a day and can easily contribute lots of additional energy to the diet.
Other drinks to consider when dieting are the alcoholic drinks. Alcohol contains a high energy content compared to carbohydrates and protein, see the chart above for details. If you regularly drink alcohol then it can affect how much weight you will be able to lose. It may necessary to cut out drinking alcohol until the weight has been lost.
The bottom line when looking at the caloric density of foods is to read the labels carefully and compare like for like. Also, try to eat a diet that is mostly made up of natural foods and ingredients as these will often have a lower calorie content overall.