European Journal of Clinical Nutrition (2015) 69, 154–161 © 2015 Macmillan Publishers Limited All rights reserved 0954-3007/15 www.nature.com/ejcn ORIGINAL ARTICLE A systematic methodology to estimate added sugar content of foods JCY Louie1,2,3, H Moshtaghian1, S Boylan2, VM Flood4,5, AM Rangan3, AW Barclay3,6, JC Brand-Miller2,3 and TP Gill2 BACKGROUND/OBJECTIVES: The effect of added sugar on health is a topical area of research. However, there is currently no analytical or other method to easily distinguish between added sugars and naturally occurring sugars in foods. This study aimed to develop a systematic methodology to estimate added sugar values on the basis of analytical data and ingredients of foods. SUBJECTS/METHODS: A 10-step, stepwise protocol was developed, starting with objective measures (six steps) and followed by more subjective estimation (four steps) if insufficient objective data are available. The method developed was applied to an Australian food composition database (AUSNUT2007) as an example. RESULTS: Out of the 3874 foods available in AUSNUT2007, 2977 foods (77%) were assigned an estimated value on the basis of objective measures (steps 1–6), and 897 (23%) were assigned a subjectively estimated value (steps 7–10). Repeatability analysis showed good repeatability for estimated values in this method. CONCLUSIONS: We propose that this method can be considered as a standardised approach for the estimation of added sugar content of foods to improve cross-study comparison. European Journal of Clinical Nutrition (2015) 69, 154–161; doi:10.1038/ejcn.2014.256; published online 17 December 2014 INTRODUCTION remain inconsistent and most methods require a high level of The term ‘added sugar’ is usually understood to mean sugar understanding of food composition to make subjective decisions, added to foods during processing. In many countries, the majority or they require additional data from the food industry. For of sugar added to food is in the form of refined sucrose, but it may example, the 59-step method proposed by Roodenburg et al.19 include other monosaccharides and disaccharides containing used average values (as proportion of total sugars) for many of the ingredients such as glucose and fructose (and their syrups), as packaged foods, for example, canned vegetables in syrup and well as corn syrup or high-fructose corn syrup (used more cornflakes, as well as data from the food industry. Many steps in regularly in the United States of America).1 Added sugar is a prime that method are also specific to a single food group. On the other target for nutrition intervention, as it provides ‘empty calories’,or hand, the method used by the US Department of Agriculture calories with little or no associated nutrients. Studies have shown (USDA) was not outlined in detail,11 precluding adoption by other that a high intake of added sugar (e.g., 420% of energy) can – researchers. Differences in product formulations between dilute the nutrient content of the diet2 5 and increase the total 22 6 7 countries also mean that methods based on food composition daily energy intake, potentially resulting in weight gain. Limiting are unlikely to be reliable in other countries without further the intake of added sugar has been advocated by many key fi 8–10 modi cation. government and public health agencies. Newer analytical methods that allow the amount of individual fi Dietary intake of added sugar is dif cult to assess accurately, as sugars to be quantified using high-performance liquid there are no analytical methods that distinguish between added chromatography23 have been incorporated in some sugar and naturally occurring sugars such as those in fruits, methods,11,19 improving the reliability of estimating added sugar vegetables and milk. Largely for this reason, the provision of content of foods. It should be noted that although high- added sugar content on food labels is not mandatory. Several performance liquid chromatography is able to identify individual countries have attempted to provide food composition databases with added sugar values estimated from the combined composi- types of sugars, it is still unable to distinguish between naturally tion and ingredient lists provided by food manufacturers.11–13 This occurring sugars and added sugars. In some cases, individual has enabled the exploration of the association between added sugar types could reasonably be assumed to be naturally sugar and health outcomes.14–18 Unfortunately, in many other occurring, for example, lactose in dairy foods. The high cost countries, including Australia, such information is not readily associated with high-performance liquid chromatography makes available. testing every single food item in the food composition database Various methods to estimate added sugar contents of foods prohibitively expensive. As a result, database providers such as have been described previously.11,19–21 Although the principle of Food Standards Australia and New Zealand have prioritised their added sugar estimation of these methods is the same, that is, laboratory testing to examine foods that are likely to contain added sugars = total sugars − naturally occurring sugars, they different types of sugars.24 1School of Medicine, Faculty of Science, Medicine and Health, The University of Wollongong, Wollongong, NSW, Australia; 2Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders, The University of Sydney, Sydney, NSW, Australia; 3School of Molecular Bioscience, The University of Sydney, Sydney, NSW, Australia; 4Faculty of Health Sciences, The University of Sydney, Sydney, NSW, Australia; 5St Vincent Hospital, Sydney, NSW, Australia and 6Australian Diabetes Council, Glebe, NSW, Australia. Correspondence: Dr JCY Louie, School of Molecular Bioscience, The University of Sydney, Level 4 East, The Hub, D17 Charles Perkins Centre, Sydney, NSW 2006, Australia. E-mail: [email protected] Received 29 May 2014; revised 9 October 2014; accepted 15 October 2014; published online 17 December 2014 Method for estimating added sugar content JCY Louie et al 155 To provide reliable between-country comparisons of added excluded, as some of them may also be yeast-free, meaning that all sugars sugar intake, a standardised objective methodology that allows for added to the recipe serve only as a sweetener and not as a processing aid. the differences in product formulation and cultural preparation of Pastries with dried fruits and/or nuts were excluded from this step, as dried foods is required. The aim of this study was to develop a fruits containing added sugar may be used, and some pastries with fillings systematic methodology to estimate added sugar values on the tend to be sweetened with sugars, and hence the group is not homogeneous; another subsequent step that can correctly take these basis of analytical data and ingredients in food products. This into consideration (e.g., step 4) should be used to estimate their added methodology was then applied to an Australian food composition 25 sugar content. table to estimate added sugar values for all foods. Step 3: Assign 100% of total sugars as added sugar for foods in the following food groups: MATERIALS AND METHODS (a) All confectionery except those containing dairy products such as fudge Definition of added sugar and chocolate. In this work, the term ‘added sugar’ was defined similarly to that used by (b) Breakfast cereals and cereal bars without fruits, chocolate, dairy or milk the USDA—that is, refined sugars added during cooking or solids. manufacturing.11 By using this definition, the following sweeteners are (c) Coffee and beverage base with no milk solids, dry or made up considered added sugars: sugar (granulated (sucrose), brown, powdered with water. and maple); monosaccharides and disaccharides (e.g., fructose, lactose, (d) Crumbed/battered meat and seafood. maltose, glucose (dextrose)); single-ingredient syrups (light corn, dark corn, (e) Processed meats. fl high-fructose corn, maple, malt, sorghum); honey and molasses; and (f) Regular soft drinks, sport drinks, avoured water and non-fruit-based maltodextrin. Despite being used as sweetening agents in some foods, energy drink. sugar alcohols were not included as added sugars in this definition, (g) Savoury biscuits, sweet biscuits, cakes and buns, donuts and batter- because they are not monosaccharides or disaccharides, and thus they are based products that do not contain fruit, chocolate or dairy products. not normally considered as ‘sugars’, such as in the Australian and New (h) Soy beverages and soy yoghurt without added fruits. Zealand Food Standards Code.26 In line with the approach of the USDA11 (i) Stock powder. and Somerset,27 undiluted fruit juice concentrate was considered as added (j) Sugar and syrups. sugar in this definition, whereas diluted fruit juice concentrates were considered to have no added sugar. This is because diluted fruit juice These food groups were selected as they contain minimal amounts of concentrates have similar composition to normal fruit juices, where the naturally occurring sugars—for example, the sugar content of plain sugar content by weight is low, making them ineffective as sweeteners. wheat flour (used in biscuits and so on) or soya beans is negligibly low 24,28 Products sweetened only with low-energy sugar substitutes (intense (o0.5 g/100 g); therefore, most, if not all, of the sugars present are sweeteners) were considered to have no added sugar. likely to be added. Step 4: Calculation based on standard recipe used in the food composition database—proportioning method where added sugar con- Proposed methodology for estimating added sugar content of tents of ALL ingredients were available from steps 1 to 3 foods Added sugar per 100 g (AS100 g) is given by the following formula: The following process outlines the methodology that we propose for – Pj estimating the added sugar content of foods, in which steps 1 6 were ´ – Wi ASi considered to be objective and steps 7 10 were considered subjective. ¼ AS ¼ i 1 Derivation of formulas used in steps 4, 5 and 6 and worked example of 100g Pj steps 4–9 are provided in Online Supplementary File 1.