Expert Nutrition

Understanding the Energy Content of Food

healthy choice

The energy content of food, more commonly known by health professionals as energy density is an important concept for you to understand regardless of whether you are trying to lose weight, put on weight, maintain weight, or require extra energy for sports performance.

To start with not all foods are created equal in regards to energy content and just because you’re not full that doesn’t mean you haven’t eaten enough. In fact some snack foods contain more energy than a complete sit down meal.

Weight Loss Tip - High calorie foods don’t necessarily fill you up. Just because you’re not full that doesn’t mean you haven’t eaten enough.

Which foods have the highest calories?

Before scrolling down to look at the table which summaries the energy content of food, why not test your current knowledge.

Which of the following foods has the greatest energy content per gram (energy density)?
A. Carbohydrates
B. Fats and oils
C. Alcohol
D. Protein
E. They are all the same.

This question is one we quiet often ask during our nutrition seminars and you’d be surprised to see many people get it wrong. Unfortunately when it comes to diet, media controls the masses and given the all the attention towards Low Carb Diets in recent years, most people choose either A. Carbohydrates or C. Alcohol, and just like the majority of the population if you were to choose either of these answers you would be wrong. The correct answer is B. Fats and Oils, which are the hands down winners of energy density.

For a more detailed answer, the energy content of food is summarised in the table below.

Energy Content of Food

Food (per gram) Energy Density
Fats 9 Cals (37.7kj)
Alcohol 7 Cals (29.3kj)
Protein 4 Cals (16.7kj)
Carbohydrates 4 Cals (16.7kj)
Fibre neg.
Vitamins and Minerals Nil

When reviewing the content of the table above not only do we need to take into consideration the energy content of food but also the role of each food within the body and its potential to be used as an energy source.

Fats and oils contain the highest energy content with 9 Calories per gram. Despite the high energy content fats and oils require more oxygen to break them down and therefore are a poor source of fuel and are preferably stored as body fat. Fat is predominately only used as a fuel source when the demand for oxygen is low such as that experienced during light intensity activity (eg walking, cooking, cleaning, sitting, reading, watching TV etc.), therefore the good news is, that because you are probably sitting down to read this webpage you are currently burning fat as your main source of fuel. More on this later.

Alcohol also contains a lot of energy, approximately 7 Calories per gram, the problem with alcohol is that it can accumulate to toxicity and as such the good news is that the body doesn’t like to store it. Therefore a beer gut isn’t really a beer gut, think about it if you could store alcohol you’d be drunk forever!

Because your body doesn’t want alcohol to accumulate to toxicity, the body preferably tries to metabolise it straight away and as a result every other source of energy that you have eaten throughout the day is now put on the back burner. So basically it’s not the alcohol that gets stored as fat but everything else you’ve eaten throughout the day. In particular alcohol combined with fatty food is not the best cocktail if your trying to lose weight.

Carbohydrates are the body’s most ideal source of fuel as they are easily broken down into glucose, which your brain cannot function without. Carbohydrates have less than half the energy content of fats and oils with only 4 Calories per gram and are the body’s preferred source of fuel, particularly during exercise. Therefore we should be very careful of any diet plan that tells us to cut out carbohydrates before the fat.

Protein has many structure roles within in the body and as such the body preferably likes to use it for growth and repair and not as a fuel source. Protein contains 4 Calories per gram and is pretty much only used for fuel as a last resort.

Fibre fills us up so we don’t eat as much, keeps our bowels healthy and helps to lower our cholesterol. Even better news is that fibre basically has no energy in it. Good weight loss diet plans normally focus on reducing fat (because of the high energy) content whilst increasing the amount of fibre (healthy, low calorie and filling). This will be discussed in the coming pages.

Vitamins and minerals play many very important roles in the body, one of which includes helping to convert fuel sources like fat, carbohydrates and protein into a useable energy source for the body. Despite their important role in the conversion of energy, vitamins and minerals themselves do not contain any energy.

Water is another essential nutrient for good health and once again the good news is that water contains no energy, so drink as much as you like.

Now that we have summarised the energy content of food, let’s see how this knowledge can help us to achieve our desired energy levels and body weight goals. Please follow the link below which is most relevant to your goal.

Learn more about energy density and how to use the energy content of food to assist you to Lose Weight

Learn more about energy density and how to use the energy content of food to assist you to Gain Weight (coming soon)

Page copy protected against web site content infringement by Copyscape


New! Comments

Have your say about what you just read! Leave me a comment in the box below.

Please share our website with your friends

SiteSell Hosting

Site Build It!

[?] Subscribe To
This Site

Add to Google
Add to My Yahoo!
Add to My MSN
Add to Newsgator
Subscribe with Bloglines

Copyright  © 2008 -2011 - All Rights Reserved