Adults limiting sugar in their drink
If you want a sparkling drink with little or no sugar, compare the caffeine in the whole can as well as the nutrition panel. A 250ml can and a 500ml can need not provide the same caffeine serving.
Who is choosing?
People stocking a shared office fridge
A mix of can sizes and flavours may suit different preferences. Check ingredients, caffeine warnings and best-before dates for each variant before committing to a multipack.
Adults who prefer a regular sweetened drink
If a regular recipe appeals more than a zero-sugar one, compare sugars per can rather than judging the drink by its fizz or can size.
What should you compare?
Start with the drink you would finish at one break, then check its caffeine and sugar figures for that full serving.
| Priority | What to check | Your needs |
|---|---|---|
| Caffeine per can | Compare the full-can amount, not just mg per 100ml. Sainsbury's lists 32mg per 100ml for Red Bull Sugarfree 250ml, equivalent to 80mg per can; Monster Energy UK lists 150mg for Monster Ultra 500ml. Check the exact variant's label. | I want to know what one can adds when I might also have coffee, tea or another caffeinated drink. |
| Sugars and sweeteners | Read sugars per 100ml and per can, and check the ingredients for sweeteners. Monster Energy UK lists 0g sugar for Monster Ultra 500ml; Tesco lists 19g sugars for Relentless Origin 500ml. | A zero-sugar drink may suit my preference, but I also want to know whether it uses sweeteners. If I choose a regular recipe, I want its full-can sugar figure. |
| Can and pack size | Check whether each can is 250ml, 355ml or 500ml, then compare pack counts and best-before dates. Size alone does not establish the caffeine amount. | For a short break, I may prefer a smaller can; for a shared fridge, I need a pack that fits the available space and will be used in time. |
| Ingredients and warnings | Check the exact can for ingredients and its high-caffeine warning. UK food-labelling guidance requires specified warning wording on drinks containing more than 150mg caffeine per litre. | When buying for colleagues, I cannot assume one recipe suits everyone's ingredient preferences or circumstances. |
What is easy to overlook?
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Comparing caffeine only per 100ml
Finishing a larger can can mean consuming a different amount of caffeine, even when two labels look similar at first glance. Monster Energy UK lists 150mg for a 500ml Monster Ultra; Red Bull lists 80mg for a 250ml Original can.
Use the full-can figure for the exact variant, and consider other caffeinated drinks you plan to have that day.
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Assuming a sparkling drink has little sugar
Fizz does not identify the sugar content. Tesco lists 19g sugars per 500ml Relentless Origin, while Monster Energy UK lists 0g for 500ml Monster Ultra.
Compare sugars for the whole can and read the ingredients separately if sweeteners matter to you.
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Buying a large multipack before checking the cans
Colleagues may have different preferences about caffeine, sweeteners and other ingredients. A multipack also takes up storage space until it is used.
Check the exact variant's ingredients, warnings, pack count and best-before date before stocking a shared fridge.
Cans that colleagues do not want still occupy fridge or cupboard space.
Brand and retailer references
These ranges illustrate differences worth checking on individual cans; a brand name alone does not identify the recipe or serving size.
Red Bull
The 250ml Original and Sugarfree cans provide smaller-format comparisons for an office break.
- Red Bull states that Original contains 80mg caffeine and 27g sugars per 250ml can. Sainsbury's lists 32mg caffeine per 100ml for Sugarfree.
- Sugarfree uses sweeteners and carries a high-caffeine warning; check the exact can's ingredients and nutrition panel.
Monster Energy
Monster Ultra is a larger, zero-sugar sparkling option in a 500ml can.
- Monster Energy UK describes Monster Ultra as citrus-flavoured and lists 0g sugar and 150mg caffeine per 500ml can.
- Check the caffeine figure on the exact variant you intend to buy; a larger can should not be treated as the same serving as a 250ml option.
Relentless
Relentless Origin is a 500ml carbonated option for someone who prefers a recipe containing sugar and sweetener.
- Tesco lists caffeine, taurine, guarana and B vitamins in Relentless Origin, with 19g sugars per 500ml can.
- Its sugar figure makes it a different choice from the zero-sugar options; compare the full nutrition panel.
Lucozade
Lucozade Alert offers a sparkling, caffeinated drink for someone seeking that range's flavour profile.
- Lucozade describes Alert as a high-caffeine sparkling range. Joybuy's product information for Alert Original lists 19.1g sugars per 500ml.
- Check the current can's nutrition panel and warning rather than applying Alert Original's figures to every variant.
Tesco
Tesco's drink listings provide product-level information for comparing different brands and can sizes.
- Its energy-drink category includes Red Bull, Monster Ultra and Relentless listings.
- Read the individual product and pack labels: a category listing does not make recipes or serving sizes interchangeable.
Joybuy options for office snacks
These Joybuy listings cover smaller and larger sparkling energy-drink cans, including sugar-free and sweetened options. Compare the exact can's caffeine, sugars and ingredients before choosing a multipack for an office.
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Red Bull Sugarfree Energy Drink 250ml, pack of 24
The 250ml cans offer a smaller sparkling serving for an office break. Sainsbury's lists 32mg caffeine per 100ml for Red Bull Sugarfree, equivalent to 80mg per can; check the can's ingredients if sweeteners matter to you. Check best-before dates before stocking the 24-can pack.
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CELSIUS Kiwi Guava, 12 × 355ml
The 355ml can sits between the smaller and larger formats shown here. For this 12-can pack, check caffeine and sugars for the full can, along with the ingredients, warnings and best-before date.
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Rockstar Blueberry & Pomegranate, 12 × 500ml
This 12-pack provides larger cans. If you expect to finish one at a break, check the exact label for caffeine and sugars per 500ml can rather than relying on per-100ml figures; also check its warning and best-before date.
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Monster Ultra White, 12 × 500ml
This is a larger zero-sugar option in a 12-can pack. Check caffeine on the exact can before choosing it for a shared fridge: figures for this listing and Monster Energy UK's Ultra information differ. Check the ingredients for sweeteners and the pack's best-before date.
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Red Bull Energy Drink 250ml, pack of 12
This 12-pack offers a smaller can in a regular, sugar-containing recipe. Red Bull states 80mg caffeine per 250ml Original can; check the current can's nutrition panel for its full-serving sugar figure before comparing it with Sugarfree.
Common questions
How do I compare caffeine in 250ml and 500ml cans?
Use the caffeine amount for the whole can, then consider any other caffeine you consume. Red Bull states 80mg per 250ml Original can, while Monster Energy UK lists 150mg per 500ml Monster Ultra can; check the exact variant's label before using either figure for a purchase.
Does sparkling mean an energy drink contains little sugar?
No. Carbonation does not tell you the sugar content: Monster Energy UK lists 0g sugar per 500ml Monster Ultra, while Tesco lists 19g per 500ml Relentless Origin. Compare sugars for the full can and check for sweeteners separately.
What does the high-caffeine warning on a can mean?
UK food-labelling guidance requires drinks with more than 150mg caffeine per litre to carry the wording “High caffeine content. Not recommended for children or pregnant or breast-feeding women”. Check the exact pack's warning, ingredients and serving size when buying for a shared office.
What should I check before stocking an office multipack?
Check the can size, pack count, ingredients, caffeine and sugars per can, warnings and best-before dates. Choose a quantity that fits the available storage space and is likely to be used before its date; follow the storage instructions on the pack.