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Diet tonic
Diet tonic by Marks & Spencers provides 3 kcal per 100 g, with 0.1 g of sugars and 0.1 g of protein. That is 98% less sugar than the average product in this category. Its Nutri-Score is C and it is classified as NOVA 4 (ultra-processed food). It is listed in the Tonic water category.
Nutrient levels per 100 g
Levels use UK front-of-pack reference thresholds.
Nutrition facts
| Nutrient | Per 100 g | Category avg |
|---|---|---|
| Calories | 3 kcal | 26 −88% |
| Total fat | 0.1 g | 0 +158% |
| Saturated fat | 0.1 g | 0 +507% |
| Carbohydrates | 0.1 g | 6 −98% |
| Total sugars | 0.1 g | 5.9 −98% |
| Added sugars | 0 g | 5.6 −100% |
| Protein | 0.1 g | 0 +119% |
| Salt | 0.1 g | 0 +302% |
*% Daily Value for 100 g, based on a 2,000-calorie diet (FDA reference values). Category average across 230 Tonic water products on Foodmetria.
Compared with other tonic water
Bar shows the share of products in this category that contain less of the nutrient.
Ingredients
Carbonated Water Lemon Concentrate (0.5% • Acid: Citric Acid • Flavourinas (With Quinine) • Preserva ive: E202, E242 • Sweetener:sucralose, Suitable for vegetarians : IMPORTANT This is a pressurised container. Open withcare• :Avoidp ical impact and extremes of temperatureasthlSS iweaken e bottle. When opening hold cap point away from people and tragile objects. IINFORMATION This product contains naturally occyrringse SERVING Best served chilled.
Additives 4
Overexposure risk is based on EFSA evaluations as recorded by Open Food Facts.
Product details
- Labels & certifications
- VegetarianGreen DotNo added sugar
- Sold in
- France, United Kingdom
- Barcode
- 00797399
Prices reported by shoppers
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Frequently asked questions
How many calories are in Diet tonic?
Diet tonic contains 3 kcal per 100 g.
How much sugar is in Diet tonic?
Diet tonic has 0.1 g of sugars per 100 g, which is considered low by UK front-of-pack guidelines.
Is Diet tonic healthy?
It has a Nutri-Score of C (A is best, E is worst); it is in NOVA group 4 — ultra-processed food. Scores describe nutritional quality and processing, not suitability for your individual diet.
Source: Open Food Facts (ODbL). Last updated March 20, 2026. Spotted a mistake? Edit this product on Open Food Facts. Not medical advice — always check the package label.
Reviews
Compare & rankings
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