/ Food & Drink, Health, Shopping

Food labels – do we need calories and kilojoules?

A food label showing calories

Most of us know how to work with calories. I know I can consume around 2,000 kcal a day as a woman, and that men are recommended 2,500 on average. So will a law to add kilojoules to packaging confuse shoppers?

For years now, we’ve gotten used to seeing the energy content of food shown in calories (kcals), and most of us understand the concept. Recipes give energy information in calories, ready meals state how many calories they contain and, more recently, a number of restaurants have started to display the calorie content of their meals.

Simpler food labels

At Which?, we’ve been campaigning for simple food labelling that gives people the information they need to help them make healthy choices. Currently, most front-of-pack labelling gives the energy content of the food in calories and the sugar, fat, saturated fat and salt in grams.

This is great news for shoppers – especially as all the major retailers have now committed to traffic light labelling as well. This means that people will finally be able to tell at a glance whether the food they’re choosing is high, medium or low in various nutrients.

However, new EU legislation will now make it compulsory for food manufacturers to label the energy content of foods in kilojoules (kJ) as well as calories. At the moment, kJ are already provided on the back-of-pack labelling. But under the new rules, if there is a front of pack label, then the energy content will have to be displayed both front and back. Those that fail to do so will be breaking the law.

Over-packing the packaging

Although kJ may be the correct scientific way to represent energy, I question how useful it will be to people. After all, how many of us really know how many kJ we should consume a day, or how many kJ are in a kcal? When we asked over 2,000 people in an online poll last August, 61%  wanted to see kcal displayed on food labels by itself. An additional 22% wanted kcal and kJ displayed together, but only 1% wanted kJ alone.

Many food manufacturers have said they’re concerned that this extra information on the front of food packages may confuse people, as well as overcrowding the packaging. Obviously, in this matter, the manufacturers’ hands are tied.

As the legislation has passed, we will soon have to get used to seeing both kJ and kcals on food packaging. But even so, I think I’ll stick to using the kcals to make a quick and informed decision about whether to buy or not. Do you use kcals, kilojoules or both when choosing your food? Do you think the extra info will crowd the packaging, or provide useful information?

What information would you like to see on food packaging?

Calories (kcals) (62%, 190 Votes)

Both calories and kilojoules (28%, 86 Votes)

Kilojoules (kJ) (10%, 29 Votes)

Total Voters: 309

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We seem to have both kJ and kcal on a lot of labels at present. That’s fine but hopefully we will move to kJ when we finally make a move to complete metrication. Those who are attempting to lose weight can have over four times as many kJ as kcal 🙂

I don’t think anyone is going to confuse a calorie and kilocalorie (kcal) but the latter is often distinguished by using a capital: Calorie.


I don’t think anyone is going to confuse a calorie and kilocalorie (kcal).

I do not agree with that, it was only recently when the joules issue started that I even knew about the kcal. I had often wondered how we humans managed to live on such a small amount of power, I now know it is 1,000 times more.

Malc.Moore says:
29 January 2013

When buying food i have always had a glance at fat Content and amount of Calories yet another grey area if one is buying Tinned Food its per 100grams or 1/2 a tin.However the likes of Tesco;Asda etc have Raised prices so much on Tinned food i no longer buy as much tinned food as i did.The Food industry spends far to much on Colorful Packaging.On frozen fish why on earth such Colorful boxes. Fish is Fish one does not need such Colorful Packaging which must add a lot to the Manufacturing costs.


At least either unit is precisely defined and we know exactly what it means, unlike ‘portion’ which seems mean whatever you want it to mean.


The portion size will be on the label, perhaps in small print. By making the portion size small it may encourage you to think that choosing that product will help you lose weight.

Look at the ‘serving suggestion’ on the front of a packet and it might just be more than a portion. 🙂


“Although kJ may be the correct scientific way to represent energy, I question how useful it will be to people.”

So, scientists are not people?? That is a new one.

The law is already there, kJ is what it will be.
The only point to make is to get rid of the redundent units and get used to it.
This rather perverse idea that we should continue to burden ourselves with dual labeling on everything is something I fail to understand.
That there should be one set of units for scientists and another set of units for people is even more perverse.
The world is moving towards one set of units, we should try to join that world, not continue to live in our own little island of “this is how we like to be”.


I’m as fed-up with lack of progress with completion of metrication as you are Brian, but there is no need to twist Shefalee’s words. 🙂

In the run-up to decimalisation in 1971 we had prices shown in both the old and new system and pounds, shillings and pence disappeared not long after. Many foods show both kJ and kcal, so it should not be a major problem to phase out the old units, though I suggest this would best be done at the same time as we tackle other aspects of metrication. We had a lot of fuss about removal of leaded petrol and that is now long forgotten for the vast majority of the population.

Malc.Moore says:
30 January 2013

Your post is rather like the Americans use the word FASCIA on Cars when the majority know it as Dashboard plain daft.

Malc.Moore says:
30 January 2013

Common sense should tell you that metrication is not popular in the UK.


The calorie was defined by a Frence physisist as “The energy requiered to raise 1 gram of water by 1 Kelvin ..etc “that sounds like metric to me.
The Joule is defined by an English scientist and is also metric.
So take your pick, metric and French or metric and English.
Either way, the joule is the SI unit now used. The calorie or Calorie (kcal or Cal) is no longer defined.
The Joule is what it is, I just detest dual labeling.


If you really want a non-metric unit then may I suggest the Btu?

Now according to a recent post I have seen, everyone in the UK knows exactly what that is.

Everyone that is except me.


Btu? I hope you are not going to start a heated argument. 🙂


Malc: Metrication is only unpopular in the UK because successive gutless governments have allowed the issue to be dragged out over at least 45 years (and still counting) rather than do what should have been done, finishing the issue in the 1970’s.

However, that’s irrelevant in this story as both calories and Joules are metric, it’s just become a case that the food and slimming industries have muddied the water, mixing up calories and kilocalories to a point that no-one knows what’s being discussed any more. Additionally, as stated elsewhere, the calorie was never the best unit for energy measurement anyway – it messed up energy itself with the effect energy has on the temperature of water (which is non-linear).

Better by far to state “Energy per 100g: 15.2kJ”. All you’ve got to do (as you do now if you’re watching your energy intake) is to tot up the Joules, and compare with your recommended daily or weekly amount (also in Joules of course).

It only gets hard if (say) the slimming industry decide (as they probably will) to mess everything up and stick with “calories” when all the food labelling is in Joules. Notice that the slimming industry already make it hard for everyone by continuing to bang on about peoples’ weights in stones and gravel despite whenever you go to the gym (or the doctors’) you weigh yourself (or get weighed) in kilos. And have done for years.


“At least either unit is precisely defined and we know exactly what it means”.

According to Wikipedia there are 8 definitions for the calorie, multiply that by two to allow for the Cal and cal confusion that makes 16 definitions. Hardly a precise unit. As its value depends on ambiant temperature it can never be precise.

That is why it has been replaced by the Joule. Love it or hate it it is here to stay.

But yes, I certainly agree those awful portions and such forth should be binned and banned in all walks of life.


This could be a very short Conversation or one that is hijacked into discussion of the merits of metrication. I would like to take it a little off-topic and ask how the energy content of food is measured and whether this is regarded as reasonably accurate. Whether we use kJ or kcal, it is useful if the figures are reasonably accurate.

I am assuming that the energy content of food is estimated from the carbohydrate/fat/protein content (Atwater system) with some corrections made to account for the presence of non-digestable fibre, etc. It is not necessary to know much about human metabolism or the bugs that form a vital part of our digestive system to realise that there are big differences between individuals. We all know people that can eat far more food than nutritional guidelines say they need and equally, there are others who hardly need to look at food to put on weight.

I can see the value of restricting the amount of fat, saturated fat and salt according to the government guidelines but I wonder if the quoted energy value of food is as useful if eating a certain number of kJ or kcal has a different effect in individuals. I suspect that some people derive more energy from dietary fibre than others.


Although a physicist myself I fully understand that for everyday living the unit used for Energy in food labelling is immaterial.
The only need is for a number that can be compared across products and with daily recommended values.
As everyone is used to Calories we should just use them and not confuse the issue with SI units.

There is absolutely no need as far as the public is concerned for the Energy to be expressed in a SI unit (kJ) to allow easy scientific calculations to be performed.
Given the tiny print often used on food labels it is all too quite to read the wrong value – keep it simple.


Another one that considers scientists and people to be a different species.
Do you not think that us plebs out here sometimes want to try to work things out also?

To be able to relate the energy used to boil a litre of water in a kettle, (Joules, Watt seconds), to the energy required to propel a 70 kg man (say) 1 km (in joules, calories are meaningless), should be a fundamental human right for all of us.

Also to relate the cost of producing that energy (for electricity and thankfully now gas in kW/h directly convertible to Joules), and the cost of food to produce the same energy is a lot easier than trying to work in Btu, kW/h, calories, feet and inches and any other daft units you experts like dream up in the pretence it makes life easier for us.

Life should not be shrouded in mystery units that most of us have no hope in remembering, understanding or converting. As a septuagenarian I would like the benefits of your advanced education to be used to better effect, not used to continue to hold the country back in the “good old days”.
The SI system has evolved and changed over many years, it is there to help us all understand the world no matter where we are or who we are. Let us all use it.


Those of us who are keen to move to kJ could do with a more convincing argument (rather than sensible suggestions) than anything I have seen so far. For me, getting rid of pounds, ounces, feet and inches is a much greater priority, and here there are plenty of excellent reasons.

Incidentally, it is kWh and not kW/h


..or 3.6 Mj (I think)


3.6 MJ actually. (Better me nitpicking than some confounded imperialist)


Brian AC if you want to work things out and relate different energy production/consumption situations then you fall into the “scientist” camp and whatever you may think you are in the minority of the population who can handle equations and understand simple scientific principles – most people cannot and do not want to.


Rarrar: you claim to be a physicist – have you wondered where physicists (and all the other scientists) come from? Yeah – they’re ordinary people who have trained up to become like that. Like you did.

The choice of what units to use for a purpose should not be up to whether or not any of the intended users are “scientists”. Choose the unit for good (scientific) reasons. That way, if a scientist wants to make use of the information, he/she can. As for everyone else, well it’s just a number to be totted up, in this case to see if you’re eating too much.

Since it’s “just a number” then a scientifically-good number should surely be preferable to a less scientifically good number? Some “ordinary” children will grow up (as you did) to become scientists (even physicists!) The fact that a mother used to tot up kJ on the food labels to keep an eye on her weight means that her children are at least basically familiar with the Joule and its multiples, and later when they train up to become scientists, that’s not an issue they’ll have to dwell on for long.

It’s the same argument for metricating the roadsigns. 99% of people won’t care, the distances and speeds on the signs are just numbers. But for those people who are (or will become) engineers it *is* important – it gets them familiar with the system they need in the “real world”. You know – the “real world” outside Britain, the one that uses km and km/h in daily life for everything involving distances and speeds. The “real world” with whom we do most of our trade and for whom we want to be building stuff, designing stuff and generally making Britain Great again.

D*mn! I just mentioned the “M” word. Forget that – the food labelling question has nothing to to do with being metric or not (both alternatives are metric). Sorry!


While I agree that in the perfect world we would all be using proper SI units and agree that moving to kilometers would be a good idea – because most of the world uses them and maps do; I see little advantage in dumping Calories in favour of kJ for food data.

Stan says:
31 January 2013

The joule is a much better unit than the calorie. The joule is derived directly from the metre kilogram and second whereas the calorie is based on the thermal properties of water, which is harder to reproduce because it requires special apparatus separate from everything else. That is why the calorie is now obsolete.
If people don’t know haw many kJ they use in a day they can soon learn and get used to it.The consumer association should not panda to people’s natural reluctance to change. Sometimes it is better to do so and any proposed changes should be considered on merit not ignorance.


You are absolutely right that reluctance to change is the biggest problem here. An accurate conversion is not needed, so if I should eat 2,500 kcal a day, I can have 10,000 kJ instead. It would be good if government did something to help move us forward. The NHS advice does not mention kJ, kcal or even Calories, but uses ‘calories’.

But I’m not sure if Which? has any involvement with endangered bamboo-eating mammals. 🙂


Wavechange, yes you are right.
The luddite government, NHS and even worse the D(a)fT all holding out for good old fashioned daft units.
Confusion conquers the masses


This ignorant human being looks at all the technical arguments above and muses quietly. I could, if I so wish, access conversion tables and work out to the nearest kJ or kcal what I should be eating, (and no doubt, for some medically challenged individuals this is essential) but, when I go shopping what I want to know is what percentage of my recommended daily allowance in fat, sugar etc I’m buying. I can then do the simple maths and balance the diet accordingly. I’m happy to leave the rest to science and the scientists. Is this so wrong, or am I missing something?


You are missing the same fact as most of the others.
If we all used the same universally derived units of measurements then the conversion tables would not be nessesary.
It is so ingrained into our (UK) culture (from the use of the Imperial system) that we need to convert everything to something else before we can use it, that we seem to loose sight of the fact that by using a standardised set of units these conversions are not requiered.
This helps us medically, mentally and mathematically challenged old folk to at least understand in part the meaning of life.


Getting back on subject, I can find no direct information regarding the EU requiring both Joules and Calories on FOP. It seems rather a strange thing for them to do, they are not usually that stupid.
My cynical guess would be if this is factual, then it is a sop to the UK government as they are the only ones in EU daft enough to want this to happen.
Where is this legislation to be found?
Personally I never even look at the calorie information for two reasons, one I don’t care and secondly I never understood it.
I would however make the effort to understand something understandable such as Joules. So, adding Joules makes a lot of sense, but only it the calorie, or is that Calorie or cal or Cal or kcal is removed as superfluous.


As mentioned above, the NHS could do with encouragement, but it would help to get those who write books and magazines about food and slimming on our side.


In answer to my own question

Article 6 on page 6
1. The declaration of the energy value and of the proportion of
nutrients or their components shall be numerical. The units to be used
are the following:
— energy — kJ and kcal
— protein
— carbohydrate
— fat
— fibre
— sodium
— cholesterol milligrams (mg)
— vitamins and minerals the units specified in the Annex

2. Information shall be expressed per 100 g or per 100 ml. In
addition, this information may be given per serving as quantified on
the label or per portion, provided that the number of portions contained
in the package is stated.

This comes into effect on 12th December 2014


Perhaps Which? could ask Flora light (“margerine”) why the FoP gives this information per 10 g on the lid and on the bottom of pack the same information it is per 100 g.
Talk about over doing the information, duplicity and confusion.
Yes, I know it is only a decimal point, but I can hardly read either even with reading glasses.
What chance would I have in store with my standard glasses?


I imagine that 10 g is considered to be a portion. Other brands of spread have a portion size of 12 g, so I guess that the manufacturer decides on portion size. Having all manufacturers give nutritional information based on 100 g makes sense.

Chuck it in the bin and relish the taste and texture of nice bread without ghastly grease. 🙂


Brian – Well done finding this on the EU Law website. I gave up trying. Having both kJ and kcal is a sensible start, in my view. Hopefully kcal will disappear in the next revision.

It’s good to see the use of sodium rather than salt, for the reason I explained elsewhere. I did manage to find how the nutritional value of fibre is calculated, which I have been wondering about for some time.


Can someone please explain how food is labelled in other countries? This might be relevant to our discussions.


I’m looking at a 500g (and that is the only weight given) box of Jordans Supreme Muesli, produced in the UK, but in Canadian bi-lingual English / French retail packaging.

The Nutrition Facts panel species the energy content “Per 3/4 cup (55 g)” for “Cereal only” and “With 1/2 cup 2% milk”.

The units are in Calories – 210 and 280 respectively.

Yes, you read that correctly. The energy content is expressed in Calories per fractional cup (6 fluid ounces of cereal and 4 fluid ounces of milk). So much for Canada being totally metric.


I have just checked a jar of French honey in my cupboard. All that has on it is the weight of 500g and a best before date of 05 May 2009, so no nutritional values back then. Maybe I should bin that someday, along with all my French 2 pin plugs. Nice Acacia honey though.


‘Wavechange’ probably poses the most sensible question yet: what does everyone else do?

After all, when it comes to road speed-limit signs, the metric counties all use km/h. Now, that’s not the S.I. unit for speed (or velocity to be precise), but it is metric, and it is the same choice of unit for the 95% of the world. Had some countries plumped for m/s instead of km/h the usefulness of everyone’s signs would have been diminished, despite it (again) being a metric vs. metric issue.

So whether that labelling is strictly S.I, I’d agree is less important than what everyone else does, but it would be sad to have to agree to use an inferior unit that suffers from such a fundamental disorder as the “calorie vs. kilocalorie vs. Calorie” naming screwup.

Even if kcal did prevail, could it please be enacted in whatever laws are applicable that the label must read “Energy content (per serving/per 100g/per kg): 200kcal” rather than the current convention which seems to be “Calories per : 200” which fails to inform its readers that these “Calorie” things (whatever sort we’re even talking about) are a unit of energy in the first place. Labelling it with the words “Energy content” does at least make people aware that it isn’t pixie dust….

I’d rather see “Energy content (per serving/per 100g/per kg): 840kJ”, but that’s just me. Whatever happens, *one* system must be decided-upon and used, not another hellish “supplementary units” compromise cop-out of the sorts our government is famous for….


wavechange.. asks how food is labelled in other countries.
The following link has a short video on how to read food panels and nutrition panels in Australia and NZ. In the examples given kilojoules (kJ) are mandatory and kilocalories (kcal) or Calories (Cal) can be supplementary. These values are always shown as being units of energy unlike the example in the photo in the Which Conversation article here which just shows a number. This puzzles me, by displaying the world “Calories 150” its just a number. Calories, kilocalories, and kilojoules must always be shown as units of energy.

Sadly the Australians are way ahead of us on this matter. They have no hesitation on displaying energy as kilojoules, the SI unit for energy. I have also been told that some organisations such as the Diabetes Foundation in both Australia and NZ, have changed their brochures, pamphlets, etc from Calories to kilojoules. This is a direct result of kilojoules only, being on nutrition labels. Its part of the public education of SI energy units.


I like the example provided by w j g. The New Zealand website not only uses kJ but shows the sodium content of food rather than salt content. It is only the sodium content of salt (sodium chloride) that is a health issue. How long will it take for the world to wake up to the fact that there are other sources of sodium in food?

Malc.Moore says:
1 February 2013

I have come to the conclusion that it’s the total it’s the total kilojoules that matter most for weight loss.I am 61 and yes it will take some time to get use to but we all look at these labels because we are people who actually care about what we want to buy many just buy by taste.I find some parents disgusting with their attitude saying i buy loads of biscuits for the kids it fills them up and its CHEAP walk into most Aldi stores and you have to walk past loads of Biscuits and i see quite a few loading there trolleys with Biscuits.Its fine eating Biscuits sometimes but not everyday to fill children up.Health starts with the youngsters at school they should be taught about kilojoules along with Budgeting hopefully the NHS will then have less overweight patients money saved can then be used for other areas that badly need it.

Malc.Moore says:
2 February 2013

I have just e-mailed Lidl to ask if they know what the German Law is on Food Labellings hopefully i will get a response in a few days time.Germany is usually very strict on Food so one hopes to learn what their take on the subject is should be interesting.


Many decades ago a recommendation was made by The Royal Society to do away with Calories /calories. In a 1972 report on nutritional sciences, it identified the problem of the continued use of calories to describe energy content of food.
“We are very much aware of the problems that arise because as a result of 30 years of education the public has an awareness of the term ‘calorie’. We cannot see any easy solution to the problem of substituting the concept that man has a requirement for the energy-yielding constituents derived from food, and this is measured in joules, …”
The Royal Society recommended editors should not allow the use of the word ‘calorie’ and provided some obvious alternatives :
for ‘calorie intake’ use ‘energy intake’
for ‘calorie requirement’ use ‘ energy requirement’


This makes a good point.
It is the mis use of words by the media that perpetuates problems.
Simply by using a different, more correct word, most of the problem is solved and a terminology issue does not arise.

Malc.Moore says:
3 February 2013

Report this comment
BrianAC You’re comment Posted 3 February 2013 at 3:58 pm about actual size of information very important not only for those with poorer eyesight for the busy mother with children has not got minutes to work out what the information is while keeping an eye on infants (What chance would I have in store with my standard glasses) whatever information given it should be a reasonable size it matters to us all whatever our opinion on actual content.I hope everyone agrees on this.Supermarkets always having to put calls out for parents when infants get lost.


Brian and Malc have made comments about text being difficult to read on food packaging. There is a good case for statutory information (ingredients, nutritional information, etc.) to be in a standard size and format so that it is easy to read. The name of the product and pictures can easily be cut down in size.

As an example of inadequate size of text, take a box of Pringles. If you can read that, your eyesight is either good or your reading glasses are the right prescription. Warning – if you read what they contain, you might not want to eat Pringles again.

Malc.Moore says:
4 February 2013

I agree wavechange but isn’t it a FACT government run scared of the Food Industry&Lobby?


I don’t know Malc, but in view of the fact that the EU has decided what information should be given to consumers (see above) they might take care of ensuring that the print is big enough to read. The EU has its uses sometimes.


With reference to my earlier comment about the recommendation made in 1972 by The Royal Society, it would be great if the EDITORS at WHICH? followed this advice.
They should not refer to food energy as calories.
Shefalee Loth, Which’s senior food researcher should ‘shed calories’ and help ensure far more people become familiar with GDA values for energy in kilojoules (kJ) and megajoules (MJ). Shefalee previously worked in the NHS so perhaps she might at least attempt to persuade NHS editors to also do away with Calories/calories.


The way most of the which? articles are written I don’t think progressive thinking is likely to happen.


After all the comments here, I was sad to see that my latest copy of “Which?” magazine featured a review of various competing chocolate digestive biscuits which mentioned how many calories each one “contained”.

It seems that most postings here show support for the idea that, regardless of whether it’s calibrated in kcal or kJ, the energy content of food should be labelled as “Energy content per 100g: “. Can’t the editors of “Which?” even reflect *that* much of the debate taking place here into the magazine??

Gordon says:
21 February 2013

This is EU wide legislation and most of europe already work in kilojoules while we insist on retaining our imperial measures. Therefore there are 3 options being: –
a. The EU imposes kilojoules on the minority that do not use them;
b. The EU imposes kilocalories on the vast majority who do not use them;
c. The EU insists on both.

The only other alternative is to have different requirements for different countries depending on their choice of units. This is a nonsense and will be used to justify higher prices, especially for those who are in the minority. I have therefore assumed this to be a non-starter.


Gordon: This is nothing to do with imperial measures…….


If the quest to use SI units were serious then we’d be buying electricity in kJ instead of kWh. The key thing here is meaningfulness. Calories, despite their quirky definition, are understood in popular culture. There’s no instance of Joules being understood in popular culture. Why throw away one of the few measurement units that people seem to be able to understand?


“There’s no instance of Joules being understood in popular culture”.

Well, that’s a problem, and that (if true) is a good reason to change. Our youngsters need to understand Joules along with the rest of the weights and measures system or we’ll never be able to generate sufficient scientists and engineers to drive our nation up in the world rankings and out of this recession.

Martin F says:
24 February 2013

We need to move to kJ and forget about Calories, an old and outdated way of trying to measure energy, from some weird equipment used to measure bombs in the early 1900s. Look up Atwater system: Totally inadequate for our modern dietary needs.


Malc.Moore says:
24 February 2013

New York State Claim using Calories is starting to change American Attitudes to-wards eating; even the Big Burger firms are supporting the introduction of how many Calories in their menu; which is a surprise there is talk that it is to go Countrywide. kilojoules will be rejected by the British Public if this happens most Ethnic British whites regard America as Britain’s Allie much more than the E.U.


“most Ethnic British whites regard America as Britain’s Allie (sic) much more than the E.U. ”

Sorry – what’s the E.U. got to do with the fact that the Joule is the S.I. unit of energy?


Do we need calories and kilojoules?
Do we need calories or kilojoules?
My thoughts on this matter is very clear, and its probably contrary to the thoughts of the good people at Which?
Food labels (nutritional labels) should have the word “Energy” on them, and the value of the energy should be in kilojoules (kJ) only.
1… The unit calorie is a metric unit, but from the older centimetre-gram-second (cgs) era of metric development. It is not a modern metric (SI) unit.
2… The UK is officially metric. It uses the modern metric system (SI). That is the standard that has been set (ie SI). Any metric labelling should be SI.
3… The SI unit for energy is the joule (kilojoule).
4… It’s always important to get it right first time. Regardless of the popularity of the older calorie unit, the joule (or kilojoule) is the correct unit.
5… Food labelling especially nutritional labelling, is not a popularity contest. It’s very important for the nations health that information on the labels use the correct units. 
Thanks for the opportunity to comment..


The joule (kilojoule) and the calorie (kilocalorie) are now starting to appear on supermarket and shop shelves.

The following link connects to an article by UKMA.



This is being driven by a new EU requirement to show both kJ and kcal. Hopefully the next step will be to get rid of kcal.

Malc.Moore says:
10 May 2013

When i read a food product information 1st i look for salt content then fat.I was horrified in Ready meals the salt content is so high i dropped the Ready meal like a hot piece of metal.I cannot understand why a can of baked beans with lower sugar&salt costs more than an ordinary can of beans surely they should be less or the same?.


It costs as much as they can get you to pay for it, that’s called capitalism. Though they probably loss lead ordinary beans a bit if they are likely to end up something like a Which? comparison shopping basket or if the industry has got one of its “1000 cheapest items” price war going on.


The UK and the US are only partially metricated, and have confused nutritional labels on packaged foods, whereas Australia that has metricated, (although not totally metric), and has clear SI units on nutritional labels.

The US has similar nutritional labeling problems to the UK, whereas Australia have no problem.

Australia has set the example that the UK and US should follow.

The following is an article from US blogger The Metric Maven it has a picture of the clear SI labeling used in Australia.



As a subscriber to “Which?” magazine, I am disappointed to learn from that article at the UKMA’s site, that the Consumers’ Association apparently lobbied the goverment to try and keep the confusing status quo mess involving kCal.

And at the expense of kJ too. What were you thinking, you guys??

It seems fairly obvious to me reading here that no-one has an issue with kJ being involved, the question seems to me mostly whether you want “just kJ” or “kJ plus kCal”.

So what the hell were the CA doing lobbying for just kCal (and getting *all* the abbreviations for just about all the units wrong too!).


The problem is that the vast majority of people are familiar with ‘calories’. I think this should always be written as Calories or kcal to distinguish them from the calorie that a scientist would use. Incidentally, it’s kcal and not kCal.

It seems logical to label food with kJ and kcal to help the public make the transition to kJ only. Prior to decimalisation in 1971, prices were shown in the new and old system for at least a year and the old £sd gradually disappeared after the changes had been introduced. This change was helped through by the fact that we had to use the new currency.

When we have labelling in kJ and kcal, those writing cookery books and recipes should get on and support the move to kJ. I am not optimistic because many writers stuck with Fahrenheit and I think it was that the oven manufacturers that helped us to move to from Fahrenheit to centigrade.


Asda now shows energy values in kilojoules (kJ) on the front of products, for example ‘Mexican Chilli Chicken’.

Daniel Clad says:
1 November 2013

1 kilojoule = 239.005736 calories. You can visit online tools to calculate kilojoules to calories

The whole concept is flawed says:
30 June 2015

The whole concept is flawed as food manufacturers and labelers have absolutely no idea of energy units. They just put what looks or sounds good.

I am a man so on average I need between 2200-2500 calories to survive. This translates to 2.2-2.5 Kcal. Let’s go with the lower figure for the moment but any one would do.
I need 2.2 Kcal. I bought a packet of ‘3 minute’ noodles which has 492 Kcal per 100 gm. The packet is 60 gm so the actual energy content of the packet is 60% of 492 = 295.2 Kcal.

Weheyyyyyyyy :)) This small 60 gram packet of ‘3minute’ noodles will last me for 134 days supplying the full amount of energy that my body needs for this period.

This labelling is not just on these noodles but on ALL products.

Before anyone has a go, let’s clarify somethinf. I am a physics graduate with a Master’s degree in Thermal Energy so I work with Joules, Calories, BTU, and their Kilo counterparts on a daily basis.

The labelling should remove the Kcal and just call it cal if that is what is meant.


Nutrition labels – who checks the quality of information provided?

Compare two bottles of distilled malt vinegar:
Same product – one with an energy value 3 times the energy value of the other.
ASDA (bar code: 2100 6296) 586 ml bottle
Energy 26 kJ per 100 ml
SAINSBURY’S (bar code: 0189 3212) 586 ml bottle
Energy 77 kJ per 100 ml
It says the ASDA is produced in Spain. For the Sainsbury’s one it’s produced in the UK.

Are Local Authority Trading Standards Officers responsible for checking the accuracy of the values stated on the nutrition labels?

Is it possible for one type of distilled malt vinegar to have an energy value about three times greater than another sample?

The values for Fat, Carbohydrate, Fibre, Protein, etc. are very similar.
These values (in grams) are shown below:
Fat 0 [ASDA] < 0.5 [SAINSBURY’S]
Carbohydrates 1.0 [ASDA] < 0.5 [SAINSBURY’S]
Fibre 0 [ASDA] < 0.5 [SAINSBURY’S]
Protein < 0.5 [ASDA] < 0.5 [SAINSBURY’S]
Salt 0 [ASDA] < 0.01 [SAINSBURY’S]

For the Sainsbury’s product it also provides the values per tablespoon (15 ml), these are given below:
Energy 12 kJ, then in the same order Fat, Carbohydrate, etc
< 0.5; < 0.5; < 0.5; < 0.5; < 0.5;


I’m glad I’m not the only one who compares the nutritional information of products and wonders why similar products differ so much. Unlike the ‘non-brewed condiment’ used in fish & chip shops, proper vinegar is fermented and could contain different amounts of acetic acid, protein and carbohydrate. As explained on Wikipedia, the description ‘distilled malt vinegar’ is a misrepresentation, since vinegar is not distilled.

Trading Standards seem to devote their time on major issues such as dangerous counterfeit goods being imported in bulk, and I very much doubt that they would be interested in dodgy nutrition labels.


It seems the food industry uses kcals and cals interchangeably. Rather strange. I’ve wondered about that for a long time.


The easy way to avoid the confusion is to use Cal to represent kcal, or better to use kJ so there is no possibility of confusion.