Choose a zero-sugar energy drink for lunch if you want caffeine as well as no sugar, but compare the amount in the whole can. Red Bull Sugarfree contains 80 mg in a 250 ml can, according to Red Bull; Monster Energy lists 150 mg for a 500 ml Ultra can and 160 mg for a 500 ml Zero Sugar can. The smaller can gives you a lower stated caffeine serving, while either 500 ml option calls for more careful accounting of coffee, tea and other caffeine consumed that day.
If you want an energy drink with no sugar alongside lunch, compare caffeine as well as the sugar declaration. Red Bull and Monster Energy list 80 mg per 250 ml Red Bull Sugarfree can, 150 mg per 500 ml Monster Ultra can and 160 mg per 500 ml Monster Energy Zero Sugar can, respectively.
If coffee or tea is already part of your day, count the caffeine in the full can before choosing a lunch drink. A 250 ml Red Bull Sugarfree can has a lower stated caffeine amount than either of the 500 ml Monster examples.
If caffeine is not the reason for your choice, a drink from the Lucozade Zero sparkling soft-drink range is another zero-sugar option, according to Lucozade. Check the particular pack if its caffeine content matters to you.
Start with whether you want an energy drink at all, then compare sugar, caffeine and can size for the product you would actually drink.
| Priority | What to check | Your needs |
|---|---|---|
| Type of drink | Decide whether you want an energy drink or a zero-sugar sparkling soft drink. If caffeine matters, check the specific pack rather than relying on “Zero” in its name. | I want something to drink with lunch, but I do not necessarily want an energy-drink caffeine serving. |
| Sugar and sweeteners | Read the sugars declaration and ingredients separately. The Red Bull Sugarfree product description identifies sucralose and acesulfame K. | A zero-sugar drink suits my lunch choice, and I also want to know which sweeteners it contains. |
| Caffeine per can | Compare the full container: Red Bull states 80 mg per 250 ml Sugarfree can; Monster Energy states 150 mg per 500 ml Ultra can and 160 mg per 500 ml Zero Sugar can. | If I will finish the can at lunch, the whole-can amount matters more to me than a figure per 100 ml. |
| Other caffeine | Include coffee, tea and other caffeine consumed that day. EFSA’s assessment of caffeine addresses intake from all dietary sources; its figures for healthy, non-pregnant adults are not targets to reach. | My lunch drink needs to fit alongside what I have already had and might drink later. |
| Pack warnings | Read the individual product warning. Sainsbury’s Red Bull Sugarfree listing carries a high-caffeine warning and says the drink is not recommended for children or pregnant or breastfeeding women. | I need to check who the pack says the drink is intended for before buying it for someone else. |
Red Bull Sugarfree and the two Monster zero-sugar energy drinks listed here all contain caffeine, according to their manufacturers.
Check caffeine for the full can and include other caffeine sources in your day.
Can size changes the amount you consume if you finish the drink: the stated examples contain 80 mg caffeine per 250 ml Red Bull can and 150 mg or 160 mg per 500 ml Monster can.
Compare whole-can amounts for the containers you are considering, alongside the sugar declaration.
The Red Bull Sugarfree product description identifies sucralose and acesulfame K in a drink without sugars.
Read the ingredients if the type of sweetener affects your choice.
These examples show why the exact drink and can size matter; a brand name alone does not establish that every product in its range is zero sugar.
Red Bull Sugarfree is a 250 ml energy-drink example for comparing a smaller can with the 500 ml options below.
Monster Energy lists two distinct zero-sugar, 500 ml energy drinks with different caffeine amounts.
Lucozade describes its Zero range as zero-sugar sparkling soft drinks, an option when an energy drink is not the aim.
The 500 ml Relentless Cherry drink listed by Sainsbury’s provides a contrast with the zero-sugar choices, not another zero-sugar example.
These options cover a 250 ml zero-sugar energy drink and two 500 ml zero-sugar energy drinks. Compare the caffeine in one can even when buying a multipack.
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A smaller-can choice when you want a zero-sugar energy drink with a stated amount of caffeine for lunch. Red Bull states 80 mg caffeine per 250 ml can; the product description identifies sucralose and acesulfame K. Count other caffeine sources and check the pack warning.
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This case suits someone choosing the 500 ml zero-sugar can rather than a smaller lunch drink. Monster Energy states 0 g sugar and 150 mg caffeine per 500 ml Ultra can. Account for the full can and consider whether the case size fits how you buy drinks.
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Another 500 ml zero-sugar energy-drink option for lunch, supplied as a four-pack. Monster Energy gives 160 mg caffeine per 500 ml for Zero Sugar and notes that its figures may vary by region. Check the purchased pack’s label and count caffeine from other drinks.
No. Red Bull states that a 250 ml Sugarfree can has 80 mg caffeine, while Monster Energy lists 150 mg for a 500 ml Ultra can and 160 mg for a 500 ml Zero Sugar can. Check caffeine separately from the sugar declaration.
Compare the caffeine in each full can if that is how much you expect to drink. The manufacturers state 80 mg for Red Bull Sugarfree 250 ml, 150 mg for Monster Ultra 500 ml and 160 mg for Monster Energy Zero Sugar 500 ml.
Yes. EFSA’s caffeine assessment considers all dietary sources. For healthy, non-pregnant adults, it concluded that single doses up to 200 mg and habitual intake up to 400 mg a day do not raise safety concerns; those figures are not intake targets, and its conclusions do not assess people with medical conditions or caffeine taken with medicines.
Do not assume so. In its September 2025 outcome, the Department of Health and Social Care confirmed a planned ban in England on sales to under-16s of drinks other than tea or coffee containing more than 150 mg caffeine per litre. The outcome does not establish an implementation date or rules for Scotland, Wales and Northern Ireland. Check the current requirements in the relevant nation and the retailer’s age policy.