Evaluation of the nutrient content of yogurts: a comprehensive survey of yogurt products in the major UK supermarkets

Abstract

Objectives: To comprehensively survey the sugar and nutrient contents of yogurt products available in UK supermarkets, in particular those marketed to children.

Design: A cross-sectional survey of yogurt products available in the UK's supermarkets in November 2016.

Methods: Data were collected from five major online UK supermarkets and a process flow strategy was used to place yogurts into eight categories: children's, dairy alternatives, dessert, drinks, fruit, flavoured, natural/Greek style and organic. A comprehensive database of product information for 921 unique products was created and analysed.

Results: The total sugar, fat, protein, calcium and energy contents were highly variable across categories, and the ranges were extremely broad. Although lower than the dessert category, the medians (range) of the total sugar content of children's (10.8 g/100 g (4.8-14.5)), fruit (11.9 g/100 g (4.6-21.3)), flavoured (12.0 g/100 g (0.1-18.8)) and organic (13.1 g/100 g (3.8-16.9)) yogurt products were all well above 10 g/100 g, and represented >45% of total energy. Only two out of 101 children's yogurt and fromage frais products surveyed qualified as low sugar (≤5 g/100 g). Natural/Greek yogurts had dramatically lower sugar contents (5.0 g/100 g (1.6, 9.5), largely lactose) than all other categories. While low-fat (<3 g/100 g) products had less sugar and energy than higher fat yogurts, nonetheless 55% (285 of 518 low-fat yogurts) contained between 10 and 20 g sugar/100 g. Within the children's category, fromage frais had higher protein (5.3 g/100 g (3.3, 8.6) vs 3.2 (2.8, 7.1); p<0.0001) and calcium contents (150 mg/100 g (90, 240) vs 130.5 mg/100 g (114, 258); p=0.0015) than yogurts.

Conclusions: While there is good evidence that yogurt can be beneficial to health, products on the market vary widely in total sugars. Fewer than 9%, and only 2% of the children's, products surveyed were low enough in sugar to earn 'green' in UK front of the pack labelling. Reformulation for the reduction of free sugars in yogurts is warranted.

Keywords: children; obesity; sugar; yogurts.

Figure 1

Process flow diagram of category decisions. Data were collected using yogurt as a search term within the UK’s top five online supermarkets between 7 October 2016 and 16 November 2016. Products were classified into different categories as shown.

Figure 2

Nutrient and energy contents of UK yogurt products across categories. (A) Sugar. (B) Fat. (C) Protein. (D) Calcium. (E) Energy. (F) Energy/serving. Data were tested for normality and analysed using the Kruskal-Wallis and Dunn’s multiple comparison tests; categories with unlike letters were significantly different. Median is indicated by black line. Dashed lines indicate thresholds defined by European Union (EU) regulations for nutrition claims for low sugar (A) and low fat (B).

Figure 3

Macronutrients compared across low-fat (≤3 g/100 g; n=530) and higher fat (>3 g/100 g; n=383) products. (A) Sugar. (B) Fat. (C) Protein. (D) Energy. Data were tested for normality and analysed using the Mann-Whitney test. Median is indicated by black line. ****P<0.0001.

Figure 4

Nutrients in children’s yogurt (n=39) and fromage frais (F Frais; n=62) products. (A) Sugar. (B) Fat. (C) Protein. (D) Calcium. (E) Energy. (F) Energy/serving. Data were tested for normality and analysed using the Mann-Whitney test. Median is indicated by black line. **P<0.01; ***P<0.001; ****P<0.0001.