Shoppers stocking up on energy drinks
If you buy several cans at once, compare the number of cans, their volume and the caffeine in each can. A larger pack does not tell you whether its serving size suits you.
Who is this choice for?
Shoppers who prefer smaller cans
Red Bull states that Sugarfree contains 80mg of caffeine in a 250ml can. Monster Energy states 150mg for a 500ml Ultra can and 160mg for a 500ml Energy Zero Sugar can, so the amount per can matters alongside pack size.
Shoppers choosing a zero-sugar soft drink
If you do not specifically want an energy drink, compare soft drinks separately. Lucozade describes its Zero range as zero-sugar sparkling drinks; that description does not make them equivalent to the energy drinks discussed here.
What should you check before buying?
Start with the drink type and its exact sugar declaration, then compare the caffeine in the can you would actually drink and the quantity you would bring home.
| Priority | What to check | Your needs |
|---|---|---|
| Sugar declaration | Read the exact sugar claim, nutrition panel and ingredients on the chosen variant. Red Bull lists sucralose and acesulfame K for Sugarfree; Monster states 0g sugar for its specified 500ml Ultra and Energy Zero Sugar cans. | I want to identify the sugar claim on the particular can, and check its sweeteners if I avoid any of them. |
| Caffeine per can | Compare the stated amount for the whole can: Red Bull Sugarfree has 80mg per 250ml; Monster Ultra has 150mg per 500ml; Monster Energy Zero Sugar has 160mg per 500ml. Include caffeine from other drinks when considering your total. | A 250ml can may fit the portion I intend to drink, or I may specifically want a 500ml can. I need to compare their caffeine amounts, not just their size. |
| Pack quantity | Check the number and volume of cans on the exact listing, then confirm that the pack and delivery option still suit your shop. | For a weekly shop, I want enough cans without choosing a case that takes more storage space than I have. |
| Drink type | Check whether the product is presented as an energy drink or a sparkling soft drink. Lucozade describes Zero as a zero-sugar soft-drink range, not as an equivalent to the specified Red Bull and Monster energy drinks. | If I mainly want a zero-sugar soft drink, I can compare those options without assuming they serve the same purpose as an energy drink. |
What is easy to overlook?
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Assuming zero sugar means little or no caffeine
The stated amounts still vary considerably by can: Red Bull Sugarfree contains 80mg per 250ml, while Monster Ultra and Monster Energy Zero Sugar contain 150mg and 160mg respectively per 500ml, according to the brands.
Check caffeine per can and remember other sources, including tea and coffee, when considering what you will drink during the day.
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Assuming a retailer listing will stay the same
A category listing may show a useful pack format, but the exact variant and its availability can change before you complete a weekly shop.
Confirm the product name, can count, can volume and delivery eligibility on the current product page.
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Treating every zero-sugar drink as an energy drink
Lucozade presents Zero as a sparkling soft-drink range, whereas the specified Red Bull and Monster energy drinks publish caffeine amounts for their cans.
Decide which type of drink you want, then check the exact label rather than relying on the sugar claim alone.
Brand and retailer references
Red Bull
Red Bull Sugarfree is a smaller-can option: Red Bull states 80mg of caffeine per 250ml can.
- Red Bull lists sucralose and acesulfame K among Sugarfree’s ingredients.
- Check the caffeine total on a different can size rather than applying the 250ml figure to it.
Monster
Monster states 0g sugar for its specified 500ml Ultra and Energy Zero Sugar cans.
- Monster states 150mg of caffeine per 500ml Ultra can and 160mg per 500ml Energy Zero Sugar can.
- The figures apply to those specified products and can sizes; check the label of the variant you buy.
Relentless
Relentless named a 500ml Zero Sugar Raspberry can in its Great Britain promotional terms in 2025.
- The name identifies a zero-sugar variant to look for if you prefer that flavour.
- Check the current can’s nutrition and caffeine label, and confirm the pack format before comparing it with other options.
Lucozade
Lucozade describes Zero as a zero-sugar sparkling soft-drink range.
- It offers a separate type of zero-sugar drink to consider for a weekly shop.
- Do not assume the range is equivalent to a caffeinated energy drink; check the particular product if caffeine matters to your choice.
Tesco
Tesco’s UK energy-drink listings include sugar-free multipacks, including Red Bull Sugar Free and Monster Energy Zero Sugar.
- Its listings provide pack counts and can volumes to compare for a weekly shop.
- Confirm the exact variant, local availability and delivery options when you shop.
Joybuy options for a weekly shop
These listings include energy-drink multipacks in different can sizes and a Pepsi Max soft-drink pack. Check the exact product and pack details before treating any option as a substitute for another.
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Monster Energy Ultra Zero Sugar 6 × 4 × 500ml
This case format is worth checking if you are stocking up on 500ml energy drinks. Monster states 150mg of caffeine per 500ml Ultra can; confirm that the listed case quantity suits your storage and intended use.
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CELSIUS Kiwi Guava 12 × 355ml
The 12-can, 355ml format offers a different pack size to compare for a weekly shop. Check the exact can’s sugar declaration, ingredients and caffeine amount before choosing it for a zero-sugar energy-drink shop.
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Pepsi Max 24 × 550ml
This is a 24-bottle, 550ml soft-drink pack, not a substitute to choose solely from energy-drink caffeine comparisons. Check the particular bottle’s label if its ingredients or caffeine content matter to you.
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Red Bull Sugarfree Energy Drink 250ml 24 Pack
The named pack offers 250ml cans for shoppers who prefer that portion size. Red Bull states 80mg of caffeine per 250ml Sugarfree can; confirm the pack count on the current listing before ordering.
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Monster Ultra White 12 × 500ml
The 12-pack consists of 500ml cans, a larger single-can portion than the 250ml options discussed above. Check the caffeine amount on this exact variant’s current can label before deciding how it fits your plans.
Questions about zero-sugar drinks
Do “no added sugar” and “zero sugar” mean the same thing?
Do not treat the claims as interchangeable when filling a weekly basket. Check the exact front-of-pack wording, nutrition panel and ingredients: the specified Monster 500ml cans state 0g sugar, while Red Bull uses the Sugarfree name and lists sucralose and acesulfame K.
Which of these energy drinks has less caffeine per can?
Of the specified Red Bull and Monster products, Red Bull states the smaller amount: 80mg in a 250ml Sugarfree can. Monster states 150mg in a 500ml Ultra can and 160mg in a 500ml Energy Zero Sugar can; compare the can you intend to drink, not just the multipack.
Is Lucozade Zero a direct alternative to a zero-sugar energy drink?
Not necessarily. Lucozade presents Zero as a zero-sugar sparkling soft-drink range, so choose it as a soft drink rather than assuming it matches the specified energy drinks’ caffeine amounts.
Is there already a UK-wide ban on selling energy drinks to under-16s?
No UK-wide ban follows from the England-specific government announcement. In July 2026, the Department of Health and Social Care and Department for Education announced a proposed ban on sales of high-caffeine energy drinks to under-16s in England from April 2027, subject to Parliamentary approval. Check the applicable rules and retailer requirements when purchasing.