Anna Rangan

Dairy consumption and overweight and obesity: a systematic review of prospective cohort studies

A comprehensive literature search was undertaken to examine the relationship between dairy consumption and overweight/obesity in prospective cohort studies. A literature search from 1980 through to April 2010 was conducted. Nineteen cohort studies met all the inclusion criteria and were included in the systematic review. Of the 19 cohort studies, 10 were among children and adolescents (aged 2 to 14 years, n = 53 to 12 829, follow‐up 8 months to 10 years) and nine among adults (aged 18 to 75 years, n = 248 to 42 696, follow‐up 2 years to 12 years). A range of dairy food exposure measures were used. Eight studies (three out of 10 studies involving children and five out of nine studies involving adults) showed a protective association against increasing weight gain (measured in various ways); one reported a significant protective association only among men who were initially overweight; seven reported no effect; one reported an increased risk (among children), and two reported both a decreased and increased risk, depending on the dairy food type. The evidence from prospective cohort studies for a protective effect of dairy consumption on risk of overweight and obesity is suggestive but not consistent, making firm conclusions difficult.

Consumption of 'extra' foods by Australian children: types, quantities and contribution to energy and nutrient intakes

Objective:To measure the types and quantities of energy-dense, nutrient-poor ‘extra’ foods consumed by Australian children and adolescents and their contribution to total energy and nutrient intakes.Design, setting and subjects:We used data from 3007 children, aged 2–18 years, who participated in the nationally representative 1995 National Nutrition Survey. Intake was determined by 24-h recall and ‘extra’ foods were defined using principles outlined in the Australian Guide to Healthy Eating (AGHE) and by applying cut points for maximum amounts of fat and sugar within each food category.Results:All children (99.8%) consumed at least one ‘extra’ food and the most commonly consumed were margarine, sugar-sweetened soft drinks, cordials and sugar. ‘Extra’ foods contributed 41% of daily energy intake. Those foods contributing most to energy intake were fried potatoes (4.2%), sugar-sweetened soft drinks (3.3%), ice cream/ice confection (3.1%) and cordials (2.7%). Age and sex were important determinants of ‘extra’ food intake, with males and older children generally consuming more and different types of, ‘extra’ foods than females and younger children. ‘Extra’ foods contributed 19% protein, 47% total fat, 47% saturated fat, 54% sugar, and approximately 20–25% of selected micronutrients to the diet. Calcium and zinc intakes from core foods were below 70% of the recommended dietary intakes for adolescent girls.Conclusions:‘Extra’ foods are over-consumed at two to four times the recommended limits and contribute excessively to the energy, fat and sugar intakes of Australian children, while providing relatively few micronutrients. This is of concern in terms of childrens weight and nutrient status.Sponsorship:DR was on placement at NSW Centre for Public Health Nutrition as part of the NSW Health Biostatistical Officer Trainee Program.

Consumption of ‘extra’ foods by Australian adults: types, quantities and contribution to energy and nutrient intakes

Objectives:To identify the types and quantities of ‘extra’ foods, or energy-dense, nutrient-poor foods, consumed by Australian adults, and assess their contribution to total energy and nutrient intakes.Subject/Methods:We used 24-h recall data from 10 851 adults, aged 19 years and over, who participated in the nationally representative 1995 National Nutrition Survey. ‘Extra’ foods were defined using principles outlined in the Australian Guide to Healthy Eating and by applying cut points for maximum amounts of fat and sugar within each food category.Results:‘Extra’ foods contributed to 36% of daily energy intake with the highest contributors being fried potatoes (2.8%), margarine (2.6%), cakes and muffins (2.5%), beer (2.4%), sugar-sweetened soft drinks (2.4%), and meat pies (2.2%). Both age and sex were important determinants of ‘extra’ foods intake; younger adults were more likely to consume sugar-sweetened soft drinks, fried potatoes, meat pies and savoury pastries, pizza, crisps, lollies and chocolate; whereas older adults were more likely to consume sweet and savoury biscuits, cakes and muffins, margarine and butter. In all age groups, ‘extra’ foods contributed more to energy intake for men than women. Overall, ‘extra’ foods contributed 16% protein, 41% total fat, 41% saturated fat, 47% sugar and approximately 20% of selected micronutrients to the diet.Conclusions:‘Extra’ foods contribute excessively to the energy, fat and sugar intakes of Australian adults, while providing relatively few micronutrients. This is of concern for the increasing risk of overweight and chronic disease and poor micronutrient status.

Higher regular fat dairy consumption is associated with lower incidence of metabolic syndrome but not type 2 diabetes

BACKGROUND AND AIMS Limited evidence suggests habitual dairy consumption to be protective against metabolic syndrome (MetSyn) and type 2 diabetes among older adults. We assessed the association of baseline consumption of dairy products with the incidence of MetSyn and type 2 diabetes among a cohort of Australian adults aged 49 years and over. METHODS AND RESULTS A validated 145-item semi-quantitative food frequency questionnaire was used to assess food and nutrient intake at baseline. Ten-year incidence of MetSyn and type 2 diabetes were obtained from 1807 and 1824 subjects respectively. Odds ratios (OR) were calculated by discrete time logistic regression modelling. Compared with subjects in the lowest intake quartile of regular fat dairy products, those in the highest quartile had a 59% lower risk of MetSyn (multivariate adjusted OR: 0.41; 95% CI: 0.23-0.71; p(trend) = 0.004), after adjustment for risk factors. Among obese subjects, an association between a high intake of regular fat dairy foods and reduced risk of type 2 diabetes was also found (age and sex adjusted OR 0.37; 95% CI: 0.16-0.88; p(trend) = 0.030), but the association did not persist after adjustment for additional confounders. There was no association between total dairy consumption and risk of MetSyn or type 2 diabetes. CONCLUSIONS We found an inverse association between regular fat dairy consumption and risk of MetSyn among Australian older adults. Further studies are warranted to examine the association between weight status, dairy consumption and risk of type 2 diabetes.

A systematic methodology to estimate added sugar content of foods

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.

Misreporting of Energy Intake in the 2007 Australian Children’s Survey: Identification, Characteristics and Impact of Misreporters

Misreporting of energy intake (EI) is a common problem in national surveys. The aim of this study was to identify misreporters using a variety of criteria, examine the impact of misreporting on the association between EI and weight status, and to define the characteristics of misreporters in the 2007 Australian Children’s Survey. Data from the 2007 Australian Children’s Survey which included 4800 children aged 2–16 years were used to examine the extent of misreporting based on EI, physical activity level (PAL), age, gender, height and weight status. Three options for identifying misreporters using the Goldberg cut-offs were explored as was direct comparison of EI to energy expenditure (TEE) in a subset of children. Linear regression was used to determine the impact of misreporting on the association between EI and weight status. The prevalence of under-reporting among all children varied from 5.0% to 6.7%, and over-reporting from 1.6% to 3.0% depending on the option used. Direct comparison of EI to TEE revealed similar results. Regression analysis showed that excluding misreporters provided the best model to examine cross-sectional associations between EI and BMI. Characteristics associated with under-reporting included older age, female, higher BMI, higher PAL, living in an urban location, lower parental education level and feeling unwell on the survey day. Over-reporting was more common among children with a lower BMI and lower PAL. In conclusion, misreporting of EI is present among various subgroups of the 2007 Australian Children’s Survey. The impact of misreporting on the association between EI and body weight should be recognised by users of this survey.

Substitution of Sugar-Sweetened Beverages with Other Beverage Alternatives: A Review of Long-Term Health Outcomes

BACKGROUND Excessive consumption of sugar-sweetened beverages (SSBs) has become an intractable public health concern worldwide, making investigation of healthy beverage alternatives for SSBs imperative. AIM To summarize the available evidence on the effects of replacing SSBs with beverage alternatives on long-term health outcomes. METHOD We systematically retrieved studies from six electronic databases from inception to November 2013. Prospective cohort studies and randomized controlled trials (RCTs) examining the effects of substituting beverage alternatives for SSBs on long-term health outcomes in both children and adults were included. The quality of included studies was assessed using the Scottish Intercollegiate Guidelines Network 50 methodology checklists. RESULTS Six cohort studies and four RCTs were included in the systematic review with the quality rating ranging from acceptable to high. Evidence from both cohort studies and RCTs showed substitution of SSBs by various beverage alternatives was associated with long-term lower energy intake and lower weight gain. However, evidence was insufficient to draw conclusions regarding the effect of beverage substitution on other health outcomes, and which beverage alternative is the best choice. CONCLUSIONS Although studies on this topic are sparse, the available evidence suggests a potential beneficial effect on body weight outcomes when SSBs are replaced by water or low-calorie beverages. Further studies in this area are warranted to fully understand the long-term health implications of beverage substitutions.

Sugar-sweetened beverages consumption in relation to changes in body fatness over 6 and 12 years among 9-year-old children: the European Youth Heart Study

Background/Objectives:In parallel with the obesity epidemic, consumption of sugar-sweetened beverages (SSB) has risen over the same period. Our aim was to investigate associations between the consumption of SSB in childhood and adolescence with subsequent changes in body fatness in early adulthood.Subjects/Methods:A longitudinal study of 9-year-old children (n=283) enrolled in the Danish part of the European Youth Heart Study with a 6-year and 12-year follow-up. Data were collected at ages 9, 15 and 21 years. Multivariate regression analyses with adjustment for potential confounders were used to evaluate the effect of SSB consumption at 9 and 15 years and change in SSB consumption from 9–15 years on subsequent change in body fatness until 21 years.Results:Subjects who consumed more than one serve of SSB daily at age 15 years had larger increases in body mass index (BMI) (β=0.92, P=0.046) and waist circumference (WC) (β=2.69, P=0.04) compared to non-consumers over the subsequent 6 years. In addition, subjects who increased their SSB consumption from age 9–15 years also had larger increases in BMI (β=0.91, P=0.09) and WC (β=2.72, P=0.04) from 15–21 years, compared to those who reported no change in consumption. No significant association was observed from 9–21 years.Conclusion:This study provides new evidence that SSB consumption in adolescence and changes in SSB consumption from childhood to adolescence are both significant predictors of change in body fatness later in early adulthood.

Dietary intake and food sources of added sugar in the Australian population.

Previous studies in Australian children/adolescents and adults examining added sugar (AS) intake were based on now out-of-date national surveys. We aimed to examine the AS and free sugar (FS) intakes and the main food sources of AS among Australians, using plausible dietary data collected by a multiple-pass, 24-h recall, from the 2011-12 Australian Health Survey respondents (n 8202). AS and FS intakes were estimated using a previously published method, and as defined by the WHO, respectively. Food groups contributing to the AS intake were described and compared by age group and sex by one-way ANOVA. Linear regression was used to test for trends across age groups. Usual intake of FS (as percentage energy (%EFS)) was computed using a published method and compared with the WHO cut-off of <10%EFS. The mean AS intake of the participants was 60·3 (SD 52·6) g/d. Sugar-sweetened beverages accounted for the greatest proportion of the AS intake of the Australian population (21·4 (sd 30·1)%), followed by sugar and sweet spreads (16·3 (SD 24·5)%) and cakes, biscuits, pastries and batter-based products (15·7 (sd 24·4)%). More than half of the study population exceeded the WHOs cut-off for FS, especially children and adolescents. Overall, 80-90% of the daily AS intake came from high-sugar energy-dense and/or nutrient-poor foods. To conclude, the majority of Australian adults and children exceed the WHO recommendation for FS intake. Efforts to reduce AS intake should focus on energy-dense and/or nutrient-poor foods.

Substituting sugar-sweetened beverages with water or milk is inversely associated with body fatness development from childhood to adolescence

OBJECTIVE The aim of this study was to examine the association between different types of beverage intake and substitution of sugar-sweetened beverages (SSBs) by water, milk, or 100% fruit juice in relation to 6-y change in body fatness. METHODS A cohort of 9-y-old children (N = 358) who participated in the Danish part of the European Youth Heart Study was followed for development of body fatness over 6 y. Multivariate linear regression was used to examine the associations between beverage intake at baseline and change in body fatness (body mass index z score [BMIz]), waist circumference (WC), and sum of four skinfolds (Σ4SF) over 6 y with adjustment for potential confounders. Substitution models were used to evaluate various beverages as alternatives to SSBs. RESULTS SSB intake at age 9 y, but not intake of other beverages, was directly associated with subsequent 6-y changes in BMIz (β = 0.05; P = 0.02) and Σ4SF (β = 0.86; P = 0.02). Daily substitution of 100 g water for 100 g SSB was inversely associated with changes in BMIz (β = -0.04; P = 0.02), WC (β =-0.29; P = 0.04), and Σ4SF (β = -0.91; P = 0.02) over 6 y. Daily substitution of 100 g milk for 100 g SSB was also inversely associated with changes in BMIz (β = -0.05; P = 0.02), WC (β = -0.33; P = 0.046), and Σ4SF (β = -0.79; P = 0.06). No effect was observed for substitution of SSB by 100% fruit juice. CONCLUSION Our results suggest that SSB intake is associated with long-term changes in body fatness in children, and replacing SSBs with water or milk, but not 100% fruit juice, is inversely associated with body fatness development.