New research reveals so-called ‘healthy’ snack bars loaded with hidden sugar

A new nationwide survey by Action on Salt and Sugar at Queen Mary University of London has exposed just how misleading many so-called ‘healthy’ snack bars really are. Despite their wholesome image, more than a third (37%) are high in sugars even under the UK’s already generous and outdated traffic-light labelling system. When judged against the tougher Chilean warning label criteria[i], the picture is even more alarming – a staggering 68% would carry a “high in sugar” warning. This matters. Recent modelling comparing traffic-light labels with stricter nutrient-warning labels shows the latter could have almost double the impact: cutting obesity rates by 4 percentage points and preventing around 110,000 obesity-related deaths.[ii]

Published to coincide with Sugar Awareness Week (w/c 17 November), the research examined 458 snack bars sold across ten of the UK’s leading supermarkets.[iii]

Despite being promoted as ‘convenient’ and ‘nutritious’, Action on Salt and Sugar’s analysis revealed wide variations in nutritional quality – with products ranging from 62 to 378 kcal in just one serving.

Using the UK’s traffic light nutrition labelling system[iv], the survey found that while some bars (28%) were considered low in total sugars, on average, each serving contained 7g of sugar – that’s nearly 2 teaspoons of sugar and equivalent to almost one-third (29%) of a 7–10-year-old child’s maximum daily limit of free sugars!

Over half (55%) were high in saturated fat. In addition, the findings reveal how misleading marketing and weak policy oversight are fuelling excess sugar intake, particularly among children and young people, through claims such as ‘source of protein’, ‘source of fibre’, ‘no added sugar’ and ‘made with whole grains’. Among those carrying “high in fibre”, nearly one-third (31%) were also high in sugars. To put this into context, M&S Dark Chocolate Date Bar contained 26.5g of sugar per serving – almost seven teaspoons – while Kellogg’s Rice Krispies Squares Caramel & Chocolate Snack Bars contained 14g per serving. Among the products with protein claims, Deliciously Ella Roasted Peanut Protein Ball contained 16g of sugars per serving. Consumers should be aware these are snack products, contain free sugars and should be consumed occasionally and in small amounts.

Table 1. Examples of higher total sugars snack bars per 100g*

*Product examples are based on per 100g to make direct and fair comparisons across products.

By comparison, the bar with the lowest sugars content was Grenade Dark Chocolate Mint Flavour 60g at 0.4g per serving (See Table 2 for further examples).[v]

Equally concerning, all products surveyed contained an average 175 kcal and 7.2g of total fat per serving.[vi] The highest-calorie product was Chia Charge Chia Seed Flapjack With Sea Salt Flakes 80g at 378 kcal per serving, followed by Chia Charge Chia Seed Flapjack With Banana 80g at 357 kcal and H&B Ginger Flapjack 80g at 347 kcal, while Skinny Crunch Light Salted Caramel 19g had the lowest at 62 kcal per serving.

Government guidance advises snacks and drinks should make up no more than 20% of our daily calories – roughly equating to two 200 kcal snacks for a moderately active woman.[vii] Yet nearly a third (32%) of the products surveyed exceeded this limit, pushing excess calories well beyond what’s recommended.

The analysis revealed that an alarming almost two-thirds (64%) of snack bars would be classified as a ‘less healthy’ product.[viii] As a result, many of these products have rightly been restricted from in-store promotion since 2023[ix] and will be banned from TV and online advertising before 9pm from January 2026. [x]

In response to the findings, Action on Salt and Sugar is urging the Government to act urgently to protect children’s health, with a clear set of policy measures to drive meaningful change. The organisation is urging ministers to:

1. Make front-of-pack labelling mandatory: Require clear, consistent colour-coded or warning labels on all food and drink (including the out-of-home) so consumers can spot unhealthy options easily.
2. Stop misleading claims: Restrict health and nutrition claims to products genuinely low in salt, sugar and saturated fat, ending the “health halo” effect.
3. Use taxes: Building on the success of the Soft Drinks Industry Levy, introduce targeted levies on foods high in salt and sugar to spur reformulation and shift shoppers towards healthier choices.

The UK’s voluntary sugar reduction programme, launched in 2016, aimed for a 20% reduction in sugar by 2020 across key food categories contributing most to children’s sugar intake. Yet the results have been dismal. Between 2016 and 2020, the average total sugar in biscuits (including cereal bars) fell by just 3.1% – far short of the target. Protein bars, despite their booming popularity and the use of the “protein” claim as a powerful marketing tool, are not clearly categorised within the sugar reduction programme, making it uncertain which, if any, guideline should apply to them. While the programme’s new product development guidance groups energy bars with cereal bars under the biscuit category, it remains unclear how bars carrying protein claims should be classified. This lack of clarity is concerning, given the rapid growth of the protein-bar market, and our findings show that although most products meet the calorie cap, 28% were still above the 20% sugar guideline for biscuits.

Dr Kawther Hashem, Senior Lecturer in Public Health Nutrition and Head of Research and Impact at Action on Salt & Sugar based at Queen Mary University of London says: “Parents and young people are being misled into believing these products are healthy when many contain excess sugar and calories. The Government must take more assertive action by mandating clear front-of-pack labelling and tightening the sugar thresholds, introducing levies on unhealthy foods, and setting ambitious healthy sales targets to truly protect children’s health.”

Nourhan Barakat, Nutritionist at Action on Salt & Sugar based at Queen Mary University of London explains: “We, as consumers, deserve honesty from food businesses and shouldn’t have to decode confusing or misleading claims. Phrases like ‘natural ingredients’, ‘high in fibre’ and ‘high protein’, can be deceptive as many of these bars can be high in sugar and saturated fat. It’s unacceptable that an average serving provides nearly one-third of a child’s recommended daily sugar intake, putting young children at risk of diet-related health conditions that they could carry with them for life.”

References

[i] Rebolledo, N., Ferrer-Rosende, P., Reyes, M., Smith Taillie, L., & Corvalán, C. (2025). Changes in the critical nutrient content of packaged foods and beverages after the full implementation of the Chilean Food Labelling and Advertising Law: a repeated cross-sectional study. BMC medicine, 23(1), 46. ed.
Table 2. Phase 3 of Chilean warning labels criteria per 100g

[ii] Evans, R., O’Flaherty, M., Putra, I. G. N. E., Kypridemos, C., Robinson, E., & Colombet, Z. (2025). The estimated impact of mandatory front-of-pack nutrition labelling policies on adult obesity prevalence and obesity-related mortality in England: a modelling study. The Lancet Regional Health–Europe.

[iii] About the product survey

• The survey looked at ‘healthy’ snack bars. ‘Healthy’ snack bars included products primarily made from cereals, oats, nuts, fruits or combinations (Table 3) and bars carrying explicit “high protein” or “protein” on pack, regardless of base ingredients. This included bars formulated with added protein (e.g. whey, soy, or pea protein) as well as protein-labelled chocolate or brownie-style bars.
• Data collection: Products were selected according to the inclusion and exclusion criteria in table 3. Full nutrition information per 100g and serving was collected or acquired between June and September 2025 from the ten retailers (Aldi, Asda, Iceland, Lidl, Marks & Spencer Morrisons, Sainsbury’s, Tesco, The Co-operative and Waitrose). We collected data online for Asda, Sainsbury’s, Tesco, Morrisons, Marks & Spencer, Iceland, Co-op and Waitrose. Aldi and Lidl provided us with their own-brand data directly, while the remaining nutrition and on-pack claims data were collected during in-store visits. M&S and Holland & Barrett products were collected from Ocado.
• Data verification: The nutrition information of the nine high sugars per 100g and the three high calorie per serving were checked online and in-store in November 2025. All retailers with five or more products were contacted for verification. Manufacturers with five or more products that are featured in this press release were contacted for verification ahead of publication. Aldi, Lidl, M&S, Asda and Kellanova confirmed their data.
• Data analysis: Nutrient Profiling Model (NPM) was applied to assess the nutritional quality of food and drink products, primarily developed for regulating advertising to children. The model assigns a score based on the balance of positive nutrients (fruit, vegetables, nuts, fibre, and protein) and negative nutrients (energy, saturated fat, total sugars, and salt). Assumptions were made when estimating fruit, vegetable, and nut content based on information declared in the ingredient lists. Dates and date paste were treated as dried or pureed fruit, and desiccated coconut was treated as a dried For products where ingredient percentages were not declared, the proportion of dates (listed as the first ingredient) was assumed to be 40%, allowing the total composition to sum to 100%.

Table 3: Data – inclusion and exclusion criteria

[iv] Department of Health. Guide to creating a front of pack nutriton label for pre-packed products sold through retail outlets. November 2016. https://assets.publishing.service.gov.uk/media/5a80cd03ed915d74e33fc7c5/FoP_Nutrition_labelling_UK_guidance.pdf

[v] Table 4 Examples of snack bars with lower sugars per 100g

[vi] In 2018, Public Health England communicated a simple rule of thumb to help people be more aware of and reduce how many calories they consume from the 3 main meals of the day, when eating on the go. The simple rule was 400:600:600 – people should aim for 400 calories from breakfast and 600 each from lunch and dinner. Behind the headlines: calorie guidelines remain unchanged – GOV.UK

[vii] BNF. Healthy Snacking at Home. https://www.nutrition.org.uk/media/jjfb3ifj/healthy-snacking-for-adults.pdf

[viii] Department of Health and Social Care, 2011. Nutrient Profiling Model (NPM). https://www.gov.uk/government/publications/the-nutrient-profiling-model The NPM considers multiple nutritional elements of a product, including energy, saturated fat, sugars and salt content, and amount of fruit, vegetable and nuts, protein and fibre to create an overall assessment of nutrition quality. The NPM is used to help determine whether a product within certain food categories would ‘fail’ and be classified as less healthy and therefore not be allowed to advertise on TV during children’s viewing time.

[ix] Gov.UK. Restricting promotions of products high in fat, sugar or salt by location and by volume price. 2023. https://www.gov.uk/government/publications/restricting-promotions-of-products-high-in-fat-sugar-or-salt-by-location-and-by-volume-price

[x] Gov.UK. 2025. Restricting advertising of less healthy food or drink on TV and online: products in scope. https://www.gov.uk/government/publications/restricting-advertising-of-less-healthy-food-or-drink-on-tv-and-online-products-in-scope/restricting-advertising-of-less-healthy-food-or-drink-on-tv-and-online-products-in-scope