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Mars Duo
Mars Duo by Mars provides 172 kcal per 100 g, with 24 g of sugars and 1.8 g of protein. That is 48% less sugar than the average product in this category. Its Nutri-Score is D and it is classified as NOVA 4 (ultra-processed food). It is listed in the Caramel chocolate bars category and comes in a 78,8g (2 x 39,4g) pack. Contains: eggs, gluten, milk, soybeans.
Nutrient levels per 100 g
Levels use UK front-of-pack reference thresholds.
Nutrition facts
Serving size: 1 bar (39.4 g)
| Nutrient | Per 100 g | Per serving | % DV* | Category avg |
|---|---|---|---|---|
| Calories | 172 kcal | 68 kcal | 474 −64% | |
| Total fat | 6.3 g | 2.5 g | 3% | 24.1 −74% |
| Saturated fat | 3 g | 1.2 g | 6% | 13.5 −78% |
| Carbohydrates | 27 g | 10.6 g | 4% | 58.3 −54% |
| Total sugars | 24 g | 9.5 g | 46.6 −48% | |
| Added sugars | 25.6 g | 10.1 g | 20% | 44.3 −42% |
| Protein | 1.8 g | 0.7 g | 1% | 6.6 −73% |
| Salt | 0.7 g | 0.3 g | 0.4 +54% |
*% Daily Value for a serving, based on a 2,000-calorie diet (FDA reference values). Category average across 97 Caramel chocolate bars products on Foodmetria.
Compared with other caramel chocolate bars
Bar shows the share of products in this category that contain less of the nutrient.
Ingredients
Sugar, glucose syrup, skimmed milk powder, cocoa butter, cocoa mass, sunflower oil, whey permeate (milk), palm fat, milk fat, fat-reduced cocoa powder, barley malt extract, salt, emulsifier (soya lecithin), egg white powder. (May contain: peanuts and other nuts).
- Allergens
- EggsGlutenMilkSoybeans
- May contain traces
- NutsPeanuts
Additives 2
Overexposure risk is based on EFSA evaluations as recorded by Open Food Facts.
Product details
- Quantity
- 78,8g (2 x 39,4g)
- Serving size
- 1 bar (39.4 g)
- Sold in
- United Kingdom
- Barcode
- 5000159551724
Prices reported by shoppers
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Frequently asked questions
How many calories are in Mars Duo?
Mars Duo contains 172 kcal per 100 g and about 68 kcal per serving (1 bar (39.4 g)).
How much sugar is in Mars Duo?
Mars Duo has 24 g of sugars per 100 g, which is considered high by UK front-of-pack guidelines.
Is Mars Duo healthy?
It has a Nutri-Score of D (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.
Is Mars Duo vegan?
Based on its ingredient list, it is not vegan.
What allergens does Mars Duo contain?
According to the label data it contains: Eggs, Gluten, Milk, Soybeans. It may also contain traces of nuts, peanuts. Recipes change — always check the package label.
Source: Open Food Facts (ODbL). Last updated June 17, 2026. Spotted a mistake? Edit this product on Open Food Facts. Not medical advice — always check the package label.
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