This study consisted of a within-subjects experiment that investigated whether the presence of the claim 'no added sugar' on a prototype chocolate-flavoured filled biscuit label with an attractive design for children influences its perception of healthiness, intention to purchase the children's carers, and size of the portion to be consumed. This cross-sectional study was conducted between March and July 2022 using a questionnaire. The qualitative analysis showed that, when evaluating the 'no sugar added' prototype, carers described these foods as 'healthier' and 'good for health', attributing greater healthiness. Further, compared with the traditional biscuit, the intention to buy and recommend to other carers, and size of the portion was higher for the prototype with the claim of 'no sugar added'. In summary, while Brazilian legislation regulates the use of this claim, its presence on food labels can mislead consumers. This can favour the greater consumption of these industrialised foods.