For a zero-sugar energy drink at a UK airport, Red Bull Zero is a 250 ml option with 80 mg caffeine per can; Monster Energy lists 150 mg for its 500 ml Monster Ultra, so check the exact variant’s label before choosing a larger can. Lucozade Zero offers a zero-sugar soft-drink alternative, but do not assume it is caffeine-free. GOV.UK says containers over 100 ml cannot pass through security at most UK airports: check your airport’s rules or buy your drink after security.
If you want caffeine without sugar in the drink, compare the whole can as well as the sugar claim. Red Bull lists 80 mg caffeine in a 250 ml Red Bull Zero can; Monster Energy lists 150 mg in a 500 ml Monster Ultra can.
Can size and variant matter when comparing caffeine servings. For pregnancy, the NHS advises no more than 200 mg caffeine a day from all sources, including energy drinks, tea and coffee; product warnings also need checking.
If you plan to carry a drink in hand luggage, check the rules at your departure and any connecting airport. GOV.UK says containers larger than 100 ml cannot pass through security at most UK airports, even when partly full.
Start with the drink’s sugar and caffeine information, then consider its container size and when you will pass through security.
| Priority | What to check | Your needs |
|---|---|---|
| Sugar and ingredients | Check sugars on the exact variant’s nutrition label and read its ingredients if sweeteners matter to you. A zero-sugar claim does not describe the caffeine content. | I want a drink without sugar, but I still need to know whether it contains caffeine or sweeteners. |
| Caffeine per can | Compare the stated amount for the whole can, not just per 100 ml. Red Bull lists 80 mg for Red Bull Zero 250 ml; Monster Energy lists 150 mg for Monster Ultra 500 ml and 160 mg for Monster Zero Sugar 500 ml. Check the exact variant’s label. | A smaller single-can caffeine serving matters to me, particularly if I have had other caffeinated drinks. |
| Security screening | Check the departure and transfer airports’ liquid rules before carrying a drink through security. According to GOV.UK, containers over 100 ml cannot pass through security at most UK airports, even if partly full. | I need to know whether the can I buy before security can travel in my hand luggage. |
| Product warnings | Read the warning on the particular can. Tesco’s Red Bull Zero listing says it is not recommended for children or pregnant or breast-feeding women; the NHS advises no more than 200 mg caffeine a day from all sources during pregnancy. | Suitability warnings affect my choice, regardless of whether a drink contains sugar. |
Zero-sugar energy drinks can still contain caffeine. Red Bull lists 80 mg per Red Bull Zero can, while Monster Energy lists 150 mg per Monster Ultra can and 160 mg per Monster Zero Sugar can in the stated sizes.
Compare caffeine per can on the exact product and account for other caffeine consumed that day.
GOV.UK says containers larger than 100 ml cannot pass through security at most UK airports, even if the container is partly full.
Check the rules for departure and any transfer airport. Where the usual restriction applies, buy a drink after security rather than packing a larger can in hand luggage.
A 500 ml can contains more drink than a 250 ml can, but the caffeine amount also depends on the variant. Monster Energy lists 150 mg for Monster Ultra 500 ml, compared with Red Bull’s 80 mg for Red Bull Zero 250 ml.
Use the caffeine figure for the whole can when deciding whether a larger format suits you.
Relentless lists sucrose in the ingredients for its Guava drink, so that product does not fit a zero-sugar requirement.
Check the sugar information for the exact flavour and variant rather than relying on the brand name.
Red Bull Zero is a compact zero-sugar energy-drink option for comparing caffeine by the can.
Monster’s zero-sugar energy-drink variants include 500 ml cans with different stated caffeine servings.
Lucozade describes its Zero range as zero-sugar sparkling drinks, offering a soft-drink route rather than a specified energy-drink caffeine serving.
Check Relentless flavours individually when looking for a zero-sugar drink.
Tesco’s online grocery information can help identify variants to compare, but it does not establish what a particular airport shop stocks.
These packs offer different can sizes for comparing drinks before an airport journey. Check the individual label for sugar, caffeine and suitability information; a product listing does not establish what is stocked at an airport terminal.
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A 250 ml can provides a compact zero-sugar energy-drink option. Joybuy’s product information lists 0 g sugars, while Red Bull lists 80 mg caffeine per can. Check the can’s high-caffeine warning; a 250 ml container exceeds the usual 100 ml limit at most UK airport security checkpoints.
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This 12-can pack has 355 ml cans. If you are choosing it for a zero-sugar drink, check the exact can’s nutrition, caffeine and suitability information before buying. A 355 ml container exceeds the usual 100 ml limit at most UK airport security checkpoints.
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A zero-sugar Monster variant to consider if you want a larger can. Joybuy describes this pack as twelve 500 ml cans; check the exact can for its caffeine and energy values rather than treating other Monster variants’ figures as interchangeable. A 500 ml container exceeds the usual 100 ml limit at most UK airport security checkpoints.
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This pack contains twelve 500 ml zero-sugar energy drinks. Check the exact can’s caffeine figure before comparing it with a smaller serving: the product listing and Monster Energy’s information for Monster Ultra give different amounts. A 500 ml container exceeds the usual 100 ml limit at most UK airport security checkpoints.
At most UK airports, not in a container larger than 100 ml, even if it is partly full, according to GOV.UK. Check the rules at your departure airport and any airport where you will pass through security again.
No. Red Bull lists 80 mg caffeine in a 250 ml Red Bull Zero can; Monster Energy lists 150 mg in a 500 ml Monster Ultra can and 160 mg in a 500 ml Monster Zero Sugar can. Check the exact variant’s label before comparing servings.
Check the caffeine amount and the product warning. The NHS advises no more than 200 mg caffeine a day from all sources during pregnancy, and Tesco’s Red Bull Zero listing says that product is not recommended for pregnant or breast-feeding women.
An online grocery listing does not establish stock at a particular airport terminal. If you need a specific drink after security, check the retailer at that terminal before relying on it.