Using a legal standard for scrutinising the regulation of food label claims, this study assessed whether consumers are misled about wholegrain (WG) content and product healthfulness based on common product labels.

First, a discrete choice experiment used pairs of hypothetical products with different amounts of WG, sugar and salt to measure effects on assessment of healthfulness; and second, a WG content comprehension assessment used actual product labels to assess respondent understanding.

Online national panel survey.

For a representative sample of US adults (n 1030), survey responses were collected in 2018 and analysed in 2019.

First, 29–47 % of respondents incorrectly identified the healthier product from paired options, and respondents who self-identified as having difficulty in understanding labels were more likely to err. Second, for actual products composed primarily of refined grains, 43–51 % of respondents overstated the WG content, whereas for one product composed primarily of WG, 17 % of respondents understated the WG content.

The frequency of consumer misunderstanding of grain product labels was high in both study components. Potential policies to address consumer confusion include requiring disclosure of WG content as a percentage of total grain content or requiring disclosure of the grams of WG v. refined grains per serving.

To develop and validate a Dental Nutrition Knowledge Competency Scale to assess dental health-related nutrition knowledge of low-income women.

This is a cross-sectional study. A literature search for foods/dietary practices related to dental caries was conducted and the items were incorporated into an initial questionnaire. A panel of ten nutrition experts evaluated it for its content, readability and relevance, and a focus group of six low-income women determined its readability and comprehension. Then the questionnaire was administered to 150 low-income women. Construct validity was evaluated by item difficulty, item discrimination and factor analysis. Internal consistency reliability was tested via Cronbach’s α. In a sub-sample of forty women, test–retest reliability was established. Paired-sample t tests were conducted to examine differences between test scores at the two time points, 2 weeks apart.

Community centres in low-income housing in Central Texas, USA.

A total of 150 low-income women, aged 18–50 years; annual household income <250 % of the federal poverty level.

Item difficulty and discrimination analysis resulted in elimination of eight questions. Factor analysis identified twenty-four items that loaded on three factors related to knowledge. These included foods/dietary practices that affect dental caries, added sugars in foods and on food labels, and recommended frequency of oral hygiene practices. The subscales and the completed scale exhibited good internal consistency (mean 0·7 (sd 0·97)) and test–retest reliability (mean 0·8 (sd 0·013)).

The Dental Nutrition Knowledge Competency Scale is a validated and reliable instrument to assess nutrition knowledge related to dental health in low-income women.

To examine the ways in which sugar-containing beverages are being portrayed as ‘better-for-you’ (BFY) via features on product labels.

Cross-sectional audit of beverage labels.

Adelaide, Australia. Data on beverage labels were collected from seventeen grocery stores during September to November 2016.

The content of 945 sugar-containing beverages labels were analysed for explicit and implicit features positioning them as healthy or BFY.

The mean sugar content of beverages was high at 8·3 g/100 ml and most sugar-containing beverages (87·7 %) displayed features that position them as BFY. This was most commonly achieved by indicating the beverages are natural (76·8 %), or contain reduced or natural energy/sugar content (48·4 %), or through suggesting that they contribute to meeting bodily needs for nutrition (28·9 %) or health (15·1 %). Features positioning beverages as BFY were more common among certain categories of beverages, namely coconut waters, iced teas, sports drinks and juices.

A large proportion of sugar-containing beverages use features on labels that position them as healthy or BFY despite containing high amounts of sugar.

The study examined two components of consumer understanding of food energy information: understanding the concept of energy and its quantity. Using this new framework, we investigated whether activity-equivalent labels facilitated interpretations of food energy compared with calorie labels and whether an image format would strengthen this facilitative effect compared with text.

We assessed the effect of energy representation and format in a 2 (activity v. calories)×2 (image v. text) between-subjects design. Conceptual understanding of energy was measured in terms of level of understanding and personal engagement. Quantitative understanding was measured in terms of participants’ estimations of a food’s contribution to their recommended daily intake and perceptions of energy values as precise or single-bound interval estimates.

The experiment was conducted online through Qualtrics.

Eight hundred and twelve participants (55 % female, age range 18–74 years) were recruited through a national survey panel in the UK.

Participants were twice more likely to have a stronger conceptual understanding of energy and four times more likely to personally engage with activity labels v. calorie labels. Participants did not differ across labels in their estimations of energy quantities; however, they inferred quantities to mean exactly the stated number of calories, but at least the stated activity duration. There were no added benefits in presenting an image over the text format.

Activity labels can facilitate conceptual understanding of energy, but may be subject to quantitative misinterpretations. Nutrition communication should consider what people infer from quantities represented on labels.

To identify ingredients from products and by-products derived from GM crops in packaged food products and to analyse the presence of these ingredients in the foods most commonly consumed by the Brazilian population.

Cross-sectional study.

A search of the scientific literature to identify the use of products and by-products derived from GM crops in foods in Brazil and a study of food labels in a supermarket belonging to one of the ten largest supermarket chains in Brazil.

To identify the ingredients present in packaged food products and their nomenclatures, the labels of all packaged food products available for sale in a supermarket were analysed. Subsequently, the presence of potential GM ingredients in the foods most commonly consumed by the Brazilian population was analysed.

A total of twenty-eight GM crops’ by-products with applications in the food industry (from soyabeans, corn, cotton and a yeast) were identified. Such by-products are presented as food ingredients or additives on food labels with 101 distinct nomenclatures. Most of the variety (63·8 %) and the quantity (64·5 %) of the foods most commonly consumed by Brazilians may contain a least one GM ingredient.

The presence of at least one potential GM ingredient was observed in more than half of the variety of foods most commonly consumed by the Brazilian population. Such ingredients were identified with distinct nomenclatures and incomplete descriptions, which may make it difficult to identify potential GM foods and confuse consumers when making food choices.

To analyse the Na content and labelling of processed and ultra-processed food products marketed in Brazil.

Cross-sectional study.

A large supermarket in Florianopolis, southern Brazil.

Ingredient lists and Na information on nutrition labels of all processed and ultra-processed pre-prepared meals and prepared ingredients, used in lunch or dinner, available for sale in the supermarket.

The study analysed 1416 products, distributed into seven groups and forty-one subgroups. Five products did not have Na information. Most products (58·8 %; 95 % CI 55·4, 62·2 %) had high Na content (>600 mg/100 g). In 78·0 % of the subgroups, variation in Na content was at least twofold between similar products with high and low Na levels, reaching 634-fold difference in the ‘garnishes and others’ subgroup. More than half of the products (52·0 %; 95 % CI 48·2, 55·6 %) had at least one Na-containing food additive. There was no relationship between the appearance of salt on the ingredients list (first to third position on the list) and a product’s Na content (high, medium or low; P=0·08).

Most food products had high Na content, with great variation between similar products, which presents new evidence for reformulation opportunities. There were inconsistencies in Na labelling, such as lack of nutritional information and incomplete ingredient descriptions. The position of salt on the ingredients list did not facilitate the identification of high-Na foods. We therefore recommend a reduction in Na in these products and a review of Brazilian legislation.

To study consumer knowledge and use of food labels.

A cross-sectional study employing both quantitative and qualitative methods. Intercept interviews were conducted with 1832 consumers at supermarket sites selected using a stratified random sampling procedure. This information was triangulated with twenty-one focus group discussions.

New Delhi and Hyderabad, two metro-cities from north and south India.

Adolescent (10–19 years), adult (20–59 years) and elderly (≥60 years) consumers.

While the national urban literacy rate is 84 %, about 99 % of the study participants were educated. About 45 % reported that they buy pre-packaged foods once weekly and about a fifth buy them every day. Taste, quality, convenience and ease of use are the main reasons for buying pre-packaged foods. Although 90 % of consumers across the age groups read food labels, the majority (81 %) looked only for the manufacturing date or expiry/best before date. Of those who read labels, only a third checked nutrition information and ingredients. Nutrient information on labels was not often read because most consumers either lacked nutrition knowledge or found the information too technical to understand. About 60 % read quality symbols. A positive association was found between education level and checking various aspects of food labels. Women and girls concerned about ‘fat’ and ‘sugar’ intake read the nutrition facts panel.

The intention of promoting healthy food choices through use of food labels is not being completely met. Since a majority of people found it difficult to comprehend nutrition information, there is a need to take up educational activities and/or introduce new forms of labelling.

The present study investigated how trans-fat is reported on the packaging of foods sold in a Brazilian supermarket.

The present descriptive, cross-sectional study analysed the ingredient list, nutrition facts label and claims of no trans-fat on the packaging.

A large supermarket in Florianópolis, Brazil.

All food products available at the supermarket.

Of the 2327 study products, more than half had components containing trans-fat in the ingredient list, especially hydrogenated vegetable fat and its alternative names. A small percentage of food products reported some trans-fat content on the nutrition facts label and roughly a quarter of the food products claimed to contain no trans-fat on the front of the packaging. There was very low agreement among the trans-fat content reported in the nutrition facts label, claims of no trans-fat made on the packaging and the ingredient list.

There was low agreement among the different ways of reporting trans-fat, suggesting that it is not possible to rely on the nutrition facts label or no trans-fat claims printed on the packaging of Brazilian food products. Hence, the Brazilian legislation on food labels needs to change to improve the reliability of food labels and to help control the trans-fat intake of the population.

The purpose of this study was to measure the reported use of nutrition information on food labels by a population of university students and to determine if label users differed from non-users in terms of gender and specific beliefs related to label information and diet–disease relationships, specifically fat and heart disease and fibre and cancer.

A single-stage cluster sampling technique was used. Data was obtained using a self-administered, validated questionnaire.

The present investigation took place at the University of Saskatchewan, Canada in the autumn of 1997.

A total of 553 students in randomly selected classes in the College of Arts and Science took part in the survey (92% response rate). The sample consisted of roughly equal numbers of males and females, most between the ages of 18 and 24.

There were approximately equal numbers of label users and non-users among males, while label users outnumbered non-users by almost four to one among females. The importance of nutrition information on food labels was the only belief that differed significantly between label users and non-users for both sexes. For females, no other beliefs distinguished label users from non-users. However, for males, significant differences were found between label users and non-users on the beliefs that nutrition information is truthful and that a relationship between fibre and cancer exists.

Females appear to use food labels more often than do males. The only consistently observed difference between label users and non-users (male and female) was that users believed in the importance of nutrition information on food labels while non-users did not.