Empty nesters stocking a small home bar
If you make drinks only occasionally, compare individual cans or bottles with a larger bottle you would need to store after opening. Choose a pack size around how often you actually use mixer.
Who are these mixers for?
Sugar-conscious gin and tonic drinkers
If reducing sugar from the mixer is your main aim, compare the stated sugars per 100ml. Tesco Finest Light and Schweppes Slimline list 0g; Sainsbury's Diet lists less than 0.5g.
Flavour-first shoppers considering a lighter tonic
If you do not require a sugar-free drink, compare tonic styles as well as their nutrition panels. A lighter-sounding name does not settle the sugar question: Fentimans Naturally Light lists 3.4g sugars per 100ml.
What matters when choosing a mixer?
Start with the sugar requirement, then compare ingredients and the amount you are likely to pour or finish after opening.
| Priority | What to check | Your needs |
|---|---|---|
| Sugars | Compare sugars per 100ml, not just “diet” or “light” on the front. Tesco Groceries lists 0g for Tesco Finest Light and Schweppes Slimline; Sainsbury's lists less than 0.5g for its Diet Indian Tonic. Fentimans lists 3.4g for Naturally Light and 4.4g for Premium Indian Tonic. | I want to know whether I am choosing a tonic with 0g listed sugars, one with a small listed amount, or one that still contains several grams per 100ml. |
| Energy | Read kcal per 100ml on the current label and consider the amount poured. Tesco Groceries lists 0kcal per 100ml for Tesco Finest Light and 2kcal for Schweppes Slimline; Fentimans lists 18kcal for Naturally Light. | For an occasional drink, I want to compare the mixer contribution using the serving size I actually pour. |
| Sweeteners | Check the ingredient list for the named sweetener. Tesco Finest Light lists sucralose; Schweppes Slimline lists aspartame and carries a phenylalanine statement; Sainsbury's Diet lists acesulfame K and sucralose. | A zero-sugar label is not enough for me if I need to avoid a particular ingredient or prefer a different sweetener. |
| Tonic ingredients | Check whether the drink is tonic water and read its ingredients for quinine. A UK leaflet published by the electronic Medicines Compendium explicitly mentions quinine in tonic water in its allergy warning. | If quinine has caused a reaction, I need to check the mixer itself rather than assume all non-alcoholic mixers have the same ingredients. |
| Pack size | Compare the size of each can or bottle, the number in the pack and the label's instructions after opening. Consider whether a larger opened bottle fits your usual drinking pattern. | Individual portions may be easier for my occasional single serves, but I also need to consider how many come in the pack. |
| Whole drink | Consider the spirit separately from the mixer. The NHS notes that mixers can add calories; Drinkaware says a typical-strength 25ml measure of gin contains about one unit of alcohol. | Choosing a diet tonic does not change the alcohol in my gin, so I want to keep track of what goes into the whole drink. |
Common buying mistakes
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Assuming “light” means zero sugar
A lighter tonic can still contain sugar: Fentimans lists 3.4g sugars per 100ml for Naturally Light.
Compare sugars per 100ml on the nutrition panel. If 0g listed sugars is your requirement, check for that figure rather than relying on the product name.
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Assuming diet tonics use the same sweetener
The listed recipes differ. Schweppes Slimline contains aspartame and carries a phenylalanine statement, while Tesco Finest Light lists sucralose.
Read the current ingredient list if a particular sweetener or phenylalanine statement matters to you.
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Counting the mixer but not the spirit
Changing tonic does not remove alcohol from a mixed drink. Drinkaware puts a typical-strength 25ml gin measure at about one unit of alcohol.
Measure the spirit separately and consider both parts of the drink when comparing servings.
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Opening a large bottle for one occasional serve
Leftover mixer needs to be stored according to its label and may not fit how often you make drinks.
Check the instructions after opening, then compare a larger bottle with the individual portions you are likely to use.
Brand ranges to compare
Fever-Tree
Its Refreshingly Light Indian Tonic is an option for shoppers comparing a lighter tonic with the brand's regular Indian Tonic.
- Fever-Tree says Refreshingly Light Indian Tonic has 50% fewer calories than its Premium Indian Tonic.
- That brand comparison does not mean the light tonic is sugar-free; check the nutrition panel for the variant you choose.
Schweppes
Slimline Tonic is a 0g-sugars-per-100ml option for shoppers prioritising the mixer's sugar listing.
- Tesco Groceries lists 0g sugars and 2kcal per 100ml for Schweppes Slimline.
- It contains aspartame; Coca-Cola Great Britain also states that it contains a source of phenylalanine.
Fentimans
Naturally Light and Premium Indian Tonic give shoppers two tonic recipes to compare when sugar-free is not essential.
- Fentimans lists 3.4g sugars and 18kcal per 100ml for Naturally Light, compared with 4.4g sugars and 20kcal per 100ml for Premium Indian Tonic.
- Naturally Light still contains sugar, so it is not a substitute for a 0g-sugars choice.
Tesco Finest
Light Indian Tonic is a 500ml bottle to compare with individual-serve formats.
- Tesco Groceries lists 0g sugars and 0kcal per 100ml and names sucralose as its sweetener.
- For occasional single drinks, check whether you would use a 500ml bottle after opening.
Sainsbury's
Diet Indian Tonic Water is a 1L bottle for shoppers comparing larger formats with their usual serving size.
- Sainsbury's lists less than 0.5g sugars and 2kcal per 100ml, with acesulfame K and sucralose among its ingredients.
- If drinks are infrequent, check the bottle's storage instructions and consider whether you would finish it after opening.
Joybuy mixers for smaller serves
These Joybuy options include Slimline tonic, light-labelled tonics and a ginger ale in individual cans or bottles. If eliminating mixer sugar matters, check the nutrition panel for the particular drink rather than treating all of these names as equivalent.
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Schweppes Slimline Tonic Water, 12 × 150ml
The 150ml cans provide individual mixer portions for occasional drinks. Tesco Groceries lists 0g sugars and 2kcal per 100ml for this pack; it contains aspartame, and Coca-Cola Great Britain states that Slimline Tonic contains a source of phenylalanine.
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Fever-Tree Refreshingly Light Mediterranean Tonic Water, 8 × 150ml
This Mediterranean tonic comes in eight individual 150ml portions. If you are considering it instead of a zero-sugar tonic, compare sugars and energy per 100ml on this variant's label; the word “Light” does not establish a 0g-sugars formulation.
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Fever-Tree Naturally Light Tonic Water, 8 × 150ml
The eight 150ml portions offer an alternative to opening one larger tonic bottle. For a sugar-based decision, check this variant's nutrition and ingredient labels rather than assuming “Naturally Light” means sugar-free.
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Fever-Tree Refreshingly Light Ginger Ale, 8 × 150ml
This is a ginger ale rather than a tonic, supplied as eight 150ml cans for individual serves. Compare its own sugars and energy per 100ml with any tonic you are considering; a light-labelled ginger ale is not automatically a zero-sugar mixer.
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Double Dutch Skinny Tonic, 24 × 200ml
The 200ml bottles provide individual portions, though a 24-bottle pack is worth weighing against how often you make drinks. Check sugars and kcal per 100ml on the current nutrition label before comparing it with zero-sugar or other light-labelled tonics; “Skinny” alone does not give those figures.
Questions about diet mixers
Does “light” tonic always mean sugar-free?
No. Fentimans lists 3.4g sugars per 100ml for Naturally Light, while Tesco Groceries lists 0g for Tesco Finest Light and Sainsbury's lists less than 0.5g for its Diet Indian Tonic. Check sugars per 100ml on the product you intend to buy.
Does diet tonic make a gin and tonic low-calorie?
A diet tonic can change the mixer's contribution, but it does not remove calories or alcohol units from the gin. The NHS notes that mixers can add calories, while Drinkaware puts a typical-strength 25ml gin measure at about one unit of alcohol; consider the amount of each ingredient poured.
Why check tonic water for quinine?
Quinine matters if you have previously reacted to it. A UK leaflet published by the electronic Medicines Compendium explicitly includes quinine in tonic water in its allergy warning. Read the mixer's ingredients, and seek advice from a clinician or pharmacist if you have had a reaction or are uncertain about its relevance to you.
What should I do with a large tonic bottle after opening?
Follow that bottle's storage instructions. If you make only occasional single drinks, compare how much you are likely to use after opening with the convenience of individual cans or bottles.