For an adult choosing one can with less caffeine at weekend breakfast, Red Bull Sugarfree contains 80 mg per 250 ml can; Monster Energy lists 150 mg for a 500 ml Ultra can and 160 mg for a 500 ml Zero Sugar can. A larger can may suit someone who wants that serving size, but compare the caffeine on the specific pack and count coffee, tea or other caffeine consumed that day. If the exact words ‘no added sugar’ matter to you, check the individual UK label rather than assuming they follow from ‘Sugarfree’ or ‘Zero Sugar’ in a product name.
The useful distinction at breakfast is the amount in the can you intend to drink, not just whether its name says sugar-free.
Red Bull Sugarfree is a 250 ml option with 80 mg caffeine per can, according to Red Bull. It gives you a smaller single-can serving than the compared 500 ml Monster drinks, although any other caffeine that day still counts.
Monster Energy lists 500 ml Ultra and Zero Sugar drinks with 150 mg and 160 mg caffeine per can respectively. Check the caffeine figure on the particular pack you buy, especially if you also have coffee or tea.
Red Bull says its sugar-free products use sweeteners instead of sugars, while a Tesco listing for Monster Energy Zero Sugar names several sweeteners. If you need the precise ‘no added sugar’ wording or avoid a particular ingredient, read the current individual label.
Start with the sugar wording you require, then compare caffeine per can rather than can size alone.
| Priority | What to check | Your needs |
|---|---|---|
| Sugar wording | Read the individual UK pack’s claim, ingredient list and nutrition panel. A product named ‘Sugarfree’ or ‘Zero Sugar’ does not, by its name alone, establish that its label says ‘no added sugar’. | I need to see the exact ‘no added sugar’ claim before choosing, rather than relying on a shop category or search result. |
| Caffeine per can | Compare both can size and caffeine on the pack. 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 have coffee or tea with breakfast, I want to account for the energy drink’s full per-can caffeine amount alongside them. |
| Ingredients | Check the current list for sweeteners and other ingredients that matter to you. Red Bull describes sweeteners in its sugar-free range; Tesco lists erythritol, sucralose, acesulfame K and guarana seed extract for a Monster Energy Zero Sugar multipack. | Zero sugar does not answer my question about which sweeteners or other listed ingredients are in the drink. |
| Pack format | Confirm whether the listing is for 250 ml or 500 ml cans and how many cans are in the pack. Use the single-can information when comparing what you plan to drink at breakfast. | A multipack may be convenient, but I am choosing the size of one serving, not comparing the total volume of two packs. |
A shopper who needs that particular wording could pick the wrong drink by relying on a product name or category filter.
Inspect the current individual UK pack or retailer label for the claim, ingredients and nutrition information you require.
Red Bull lists 80 mg caffeine in a 250 ml Sugarfree can, while Monster Energy lists 150 mg or 160 mg in the compared 500 ml zero-sugar cans. Those are different contributions from one can at breakfast.
Check caffeine per can on the pack and include other sources, such as coffee and tea, when considering your day’s intake.
Red Bull describes sweeteners in its sugar-free range, and Tesco’s Monster Energy Zero Sugar ingredient listing names erythritol, sucralose and acesulfame K.
Read the current ingredient list if you avoid a particular sweetener or want to check for ingredients such as guarana seed extract.
These references help distinguish named drinks and listings; a brand name alone does not establish the sugar claim or caffeine content of every product it sells.
Red Bull Sugarfree is a 250 ml sugar-free option.
Monster Energy describes both Ultra and Monster Energy Zero Sugar as 500 ml zero-sugar drinks.
Relentless is another energy-drink brand to assess product by product.
Lucozade describes Alert as a high-caffeine drink.
Tesco’s sugar-free energy-drink category includes listings for named Red Bull and Monster products.
These packs offer a smaller Red Bull Sugarfree can and larger Monster zero-sugar cans for the breakfast choice. Check each pack’s current label if the exact ‘no added sugar’ claim or a particular caffeine figure is decisive.
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The smaller-can option if you plan to drink one can at breakfast. Red Bull states that Sugarfree contains 80 mg caffeine per 250 ml can. Check the current pack if you need the exact ‘no added sugar’ wording or want to review its sweeteners.
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A four-pack for someone choosing a 500 ml zero-sugar can rather than a smaller serving. Read this pack’s caffeine information before deciding how it fits alongside coffee, tea or other caffeine; also check its label if you require the exact ‘no added sugar’ claim.
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This pack offers four 500 ml zero-sugar cans. Monster Energy states 150 mg caffeine per 500 ml Ultra can, but the caffeine figures associated with this listing differ; check the current can label before relying on a per-can amount. Check the same label if the precise ‘no added sugar’ wording matters to you.
Do not assume the exact ‘no added sugar’ wording from ‘Zero Sugar’ or ‘Sugarfree’ in a product name. If that claim is a requirement for your purchase, check the current individual UK pack or retailer label before buying.
Red Bull states that Sugarfree contains 80 mg per 250 ml can, compared with Monster Energy’s figures of 150 mg per 500 ml Ultra can and 160 mg per 500 ml Zero Sugar can. These are manufacturer figures for the named drinks; check the particular can’s label, especially where a retailer listing gives different information, and account for other caffeine consumed that day.
No. The NHS lists energy drinks among caffeine sources and advises no more than 200 mg caffeine a day during pregnancy. Sugar-free wording does not remove caffeine, so check the drink’s label and caffeine from other sources; ask your midwife about your circumstances.