Current food labelling practices in online supermarkets in Australia

BACKGROUND

Food product labelling can support consumer decision-making. Several food product labels (nutrition information panels (NIPs), ingredients lists, allergen declarations and country-of-origin) are mandated for physical product packaging in Australia, with a voluntary front-of-pack nutrition labelling system, Health Star Ratings (HSRs), also available. However, labelling requirements are not explicitly extended to online settings and the extent to which this information is available in these increasingly important food environments has not been assessed.

METHODS

Data from all individual food product pages was collected from the online stores of the two dominant supermarket retailers in Australia using automated web scraping in April-May 2022 (n = 22,077 products collected). We assessed the proportion of pages displaying NIPs, ingredients, allergens, country-of-origin and HSRs after excluding products ineligible to display the respective label. We also assessed whether HSRs were differentially available for higher- (healthier) and lower-scoring (less healthy) products, with HSR scores drawn from a comprehensive Australian food composition database, FoodSwitch. A manual inspection of randomly selected product pages (n = 100 for each label type per supermarket), drawn from products displaying the relevant label, was conducted to assess whether the labels were immediately visible to users (i.e. without scrolling or clicking). Differences in labelling prevalence and visibility were compared using chi-squared tests.

RESULTS

Across both supermarkets, country-of-origin labelling was almost complete (displayed on 93% of food product pages), but NIPs (49%), ingredients (34%) and allergens (53%) were less frequently displayed. HSRs were infrequently displayed (14% across both supermarkets) and more likely to be applied to higher-scoring products (22% on products with ≥ 3.5HSR v 0.4% on products with < 3.5HSR, p < 0.001). One supermarket was far more likely to make NIPs (100% v 2%, p < 0.001), ingredients (100% v 19%, p < 0.001) and allergens (97% v 0%, p < 0.001) information immediately visible, though the other made HSRs more apparent (22% v 75%, p < 0.001). Both supermarkets displayed country-of-origin labels prominently (100% v 86%, p < 0.001).

CONCLUSIONS

Food product labelling varies in online supermarkets in Australia overall and between supermarkets, while the design of online stores resulted in differences in labelling visibility. The near-complete display of country-of-origin labels and differential application of HSRs to higher-scoring products may reflect their use as marketing tools. Our findings highlight an urgent need for food labelling regulations to be updated to better account for online retail food environments.

The Association Between Coffee Consumption and Metabolic Syndrome in Adults: A Systematic Review and Meta-Analysis

Previous meta-analyses that found an inverse association between coffee consumption and metabolic syndrome pooled data from cross-sectional and longitudinal studies, which could lead to potentially misleading conclusions. Hence, this work aimed to reassess this association by analyzing data from the 2 types of studies separately and including recent studies. Online databases including PubMed, Scopus, Embase, The Cumulative Index to Nursing and Allied Health Literature (CINAHL) Plus, and Science Direct were searched for relevant studies published up to July 2020. Both cross-sectional and longitudinal studies were included if published after 1999, reported both effect estimates and CIs, and presented results adjusted for confounding variables. Data of the highest coffee consumption level in each study, as well as those of medium consumption levels in studies with ≥3 consumption categories, were pooled using random-effect models, with sex-stratified and sex-adjusted results being analyzed separately. Results were obtained based on data from 13 cross-sectional studies involving 280,803 participants and 2 longitudinal studies involving 17,014 participants. The overall sex-adjusted association of the highest consumption level was not significant (n = 9 studies; OR: 0.88; 95% CI: 0.70, 1.10; I2: 91.5%) and the 2 longitudinal studies both yielded no association. Subgroup analysis revealed inverse associations in both males and females, as well as in Caucasians with medium coffee consumption (n = 4 studies, OR: 0.88; 95% CI: 0.84, 0.93; I2: 0%). Although residual confounding could affect the results of this meta-analysis, our findings suggested with a low certainty that coffee consumption may not be associated with metabolic syndrome, a finding that is different from those of previous meta-analyses and could be due to variation in characteristics of study participants. More longitudinal studies are also needed to further assess the temporal association between coffee consumption and metabolic syndrome. This meta-analysis was registered at https://www.crd.york.ac.uk/prospero as CRD42018110650.

Trends in food sources of added sugar in Australian eating patterns between 1995 and 2012 using national consumption survey data

BACKGROUND

When aiming to develop dietary messaging to achieve reductions in added sugar intakes, it is necessary to identify key food contributors. Food contributors are not expected to remain static over time. Therefore, the present study aimed to compare the total added sugars (AS) intake and related food sources for adult respondents of two Australian national consumption surveys.

METHODS

Repeated 24-h recall data from the 1995 National Nutrition Survey (1995NNS, n = 10 851) and the 2011-12 National Nutrition and Physical Activity Survey (2012NNPAS, n = 9341) was used to estimate AS consumption. Food group sources of AS were examined per consumer and per capita and the food group predictors of energy provided by AS were determined.

RESULTS

A significant difference in total AS intake was identified by age and gender between the surveys (all P < 0.001). Increased variability in food group contributions per consumer was also identified. Nine of the top 20 food groups from the 1995NNS differed (P < 0.001) in their contribution to AS in 2012NNPAS per consumer. Fewer changes were apparent at the population level, with >40% AS coming from only three food groups. Age-stratified analyses showed that the 'sugar, honeys and syrups' and the 'sweetened beverages' food groups were the top contributors between the surveys up to the age group of 70 years. 'Sugar, honey and syrups', 'chocolate and chocolate-based confectionery,' and 'other confectionery' (all, P < 0.001) were significant predictors of AS intake (1995NNS, r²  = 0.755; 2012NNPAS r²  = 0.740).

CONCLUSIONS

At a population level, food group contributions to AS intakes for Australian adults have not changed substantially over time, yet notable shifts in AS can be seen when targeting only the consumers of these food sources. 'Cake type desserts' appear to be increasingly consumed though 'sweetened beverages' remain a major contributor to AS intakes warranting targeted public health strategies.

Methodology for the assessment of added/free sugar intake in epidemiological studies

PURPOSE OF REVIEW

High-sugar intake has been linked to increased risk of diseases but an accurate assessment of added/free sugar intake has always been a challenge in research. This review summarizes the methodologies for assessing added/free sugar intake reported in recent literature.

RECENT FINDINGS

Four different methods for added/free sugar-intake assessment are discussed, including the carbon isotope ratio (δC) method, Food Patterns Equivalent Database, disaggregation method and the 10-step systematic method. These methods have different strengths and limitations in terms of requirement for background knowledge, flexibility to sugar definition, level of subjectivity, accuracy and needs for recalculation/modification when used in different countries or food products.

SUMMARY

Although advances have been made in the methodologies for assessing added/free sugar intake, accurate assessment continues to be difficult. Of the methods reviewed, the 10-step systematic method could be a simpler method to provide relatively accurate estimation of added/free sugar intake. Further improvements or combining with other methods may allow more accurate and flexible estimation. Development of a completely objective biomarker for added/free sugar intake is unlikely to be achievable, therefore future research may need to focus on developing correction equations for use with biomarkers such as δC to improve their specificity to added/free sugar intake.

Effects of Lactic Acid Bacteria-Fermented Soymilk on Isoflavone Metabolites and Short-Chain Fatty Acids Excretion and Their Modulating Effects on Gut Microbiota

Lactobacillus rhamnosus strain ASCC 1520 with high soy isoflavone transformation ability was used to ferment soymilk and added to the diet of mice. The impact of L. rhamnosus fermentation on soy isoflavone metabolites and intestinal bacterial community, in conjunction with fecal enzyme activity and short-chain fatty acids (SCFA) excretion was evaluated. Antibiotics intervention resulted in a decrease in fecal enzyme activities and SCFA. Although long-term intake of soymilk or L. rhamnosus-fermented soymilk did not affect the fecal β-glucuronidase and β-galactosidase activities, it improved the β-glucosidase activity when antibiotics were concomitantly administered. Soymilk or fermented soymilk administration increased the isoflavone metabolites (O-DMA and equol) excreted in urine. Antibiotics decreased the daidzein excretion and its metabolites but showed little effect on glycitein and genistein excretion. Principal coordinates analysis (PCoA) of the 16s rRNA gene sequencing data found a remarkable shift in gut microbiota after soymilk administration and antibiotics treatment. Matastats test of the relative abundance of bacterial taxa revealed Odoribacter (Bacteroidales family), Lactobacillus (Lactobacillales order), and Alistipes (Rikenellaceae family) were enriched in soymilk while bacterial taxa from Bacteroides and Lactobacillus were enriched in L. rhamnosus-fermented soymilk. Furthermore, there was less decrease in bacterial taxa with fermented soymilk group even when antibiotics were concomitantly administered. Overall, this study revealed that the gut microbiota of a healthy host is enough for the whole isoflavone metabolism under normal conditions. Feeding mice with L. rhamnosus-fermented soymilk improved fecal enzyme activity and kept the balance of the gut mirobiota when antibiotics were used. PRACTICAL APPLICATION: Feeding mice with L. rhamnosus-fermented soymilk improved fecal enzyme activity and kept the balance of the gut mirobiota when antibiotics were used.

Explaining variance in self-directed learning readiness of first year students in health professional programs

BACKGROUND

Self-directed learning (SDL) is expected of health science graduates; it is thus a learning outcome in many pre-certification programs. Previous research identified age, gender, discipline and prior education as associated with variations in students' self-directed learning readiness (SDLR). Studies in other fields also propose personality as influential.

METHOD

This study investigated relationships between SDLR and age, gender, discipline, previous education, and personality traits. The Self-Directed Learning Readiness Scale and the 50-item 'big five' personality trait inventory were administered to 584 first-year undergraduate students (n = 312 female) enrolled in a first-session undergraduate interprofessional health sciences subject.

RESULTS

Students were from health promotion, health services management, therapeutic recreation, sports and exercise science, occupational therapy, physiotherapy, and podiatry. Four hundred and seven responses (n = 230 females) were complete. SDLR was significantly higher in females and students in occupational therapy and physiotherapy. SDLR increased with age and higher levels of previous education. It was also significantly associated with 'big five' personality trait scores. Regression analysis revealed 52.9% of variance was accounted for by personality factors, discipline and prior experience of tertiary education.

CONCLUSION

Demographic, discipline and personality factors are associated with SDLR in the first year of study. Teachers need to be alert to individual student variation in SDLR.

Pattern of omega-3 polyunsaturated fatty acid intake and fish consumption and retinal vascular caliber in children and adolescents: A cohort study

We aimed to investigate whether fish and long chain omega-3 polyunsaturated fatty acid (LCn-3 PUFA) consumption changed appreciably during adolescence. We also assessed whether these dietary variables are associated with retinal microvascular signs (possible markers of future cardiovascular disease risk). 633 children had dietary data at ages 12 and 17. Fish and LCn-3 PUFA [eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA)] intake was assessed by a food frequency questionnaire. Retinal vessel caliber was quantified from digital photographs using computer software. Mean energy-adjusted intakes (mg/day) of total LCn-3 PUFA, EPA, and DHA at age 12 were 297.1±261.1; 102.5±106.9; and 129.7±137.7, respectively; and this increased significantly at age 17 to: 347.0±324.0 (p<0.0001); 122.5±132.7 (p = 0.0001); and 160.3±171.4 (p <0.0001), respectively. Increasing quartiles of LCn-3PUFA intake were associated with widening of mean retinal arteriolar caliber among 17-year old girls ~3.9 μm (multivariable-adjusted P-trend = 0.001). Girls who consumed ≥2 serves of fish/week versus those who did not had ~2.1 μm wider retinal arterioles (p = 0.03). No associations were observed among boys or with retinal venules. Mean dietary intakes of LCn-3 PUFA increased during adolescence, but are still below recommended levels of consumption. These results suggest that LCn-3 PUFA and fish intake might have a beneficial influence.

Trends in added sugar intake and food sources in a cohort of older Australians: 15 years of follow-up from the Blue Mountains Eye Study

BACKGROUND

The trend of added sugar (AS) intake has not been investigated in the Australian population, including in older adults. The present study aimed to assess trends and food sources of AS intake among a cohort of older Australians during 15 years of follow-up.

METHODS

Dietary data from participants of the Blue Mountains Eye Study (1264 men and 1614 women), aged ≥49 years at baseline, were collected. Dietary intakes were assessed at 5-yearly intervals (1992-94 to 2007-09) using a 145-item food frequency questionnaire (FFQ). AS content of FFQ food items was estimated using a stepwise systematic method. Trends for AS intake between baseline and the three follow-up periods were assessed using linear mixed modelling.

RESULTS

In men, the mean (SEM) percentage of energy provided by AS intake (EAS%) declined from 10.4% (0.1%) at baseline to 9.4% (0.2%) at 15-year follow-up (P_trend = 0.028). Women's mean (SEM) EAS% intake at baseline and 15-year follow-up was 9.2% (0.1%) and 8.8% (0.2%), respectively (P_trend = 0.550). EAS% intake of men was significantly higher than that of women for 10 years (P < 0.05). Sugar products (table sugar, syrup, jam and honey) were the major sources of AS at all-time points and contributed to more than 40% and 35% of AS intake in men and women, respectively. Intake of sugar products decreased in men during follow-up (P_trend < 0.001).

CONCLUSIONS

An overall downward trend was observed in AS intake in both genders, however, was only significant for men during 15 years of follow-up. Table sugar and sugar-containing spreads represent the major source of AS in this cohort of older Australians.

Effects of a low-glycemic index diet during pregnancy on offspring growth, body composition, and vascular health: a pilot randomized controlled trial

BACKGROUND

Elevated maternal blood glucose concentrations may contribute to macrosomia, adiposity, and poorer vascular health in the offspring.

OBJECTIVE

The aim was to explore the effect of a low-glycemic index (low-GI) diet during pregnancy on offspring growth, adiposity, and arterial wall thickness during infancy.

DESIGN

This was a longitudinal follow-up study in a self-selected subgroup of mother-infant pairs (n= 59) participating in a larger randomized trial comparing the effects on perinatal outcomes of a low-GI diet and a conventional high-fiber (HF) diet during pregnancy. Infant anthropometric measurements were taken every month for 6 mo and then at 9 and 12 mo of age. Adiposity was assessed at birth and at 3 mo by air-displacement plethysmography by using the Pea Pod system (Cosmed) and at 6 and 12 mo by bioimpedance analysis (Bodystat). Aortic intima-media thickness was assessed at 12 mo by high-resolution ultrasound (Philips).

RESULTS

Maternal dietary GI was lower in the low-GI group than in the HF group (51 ± 1 compared with 57 ± 1;P< 0.001). No differences in neonatal outcomes were observed in the main trial. In the self-selected subsample, birth weight and length z scores were lower in the low-GI group than in the HF group (birth weight z score: 0.2 ± 0.2 compared with 0.7 ± 0.2, respectively;P= 0.04; birth length z score: 0.3 ± 0.2 compared with 0.9 ± 0.2, respectively;P= 0.04), but adiposity from birth to 12 mo of age and growth trajectories from 1 to 12 mo of age were similar. Aortic intima-media thickness was lower in the low-GI group than in the HF group (657 ±12 compared with 696 ± 12 μm, respectively;P= 0.02), which was partly mediated by differences in birth weight.

CONCLUSION

In women at risk of gestational diabetes mellitus, a low-GI diet influences offspring birth weight, birth length, and arterial wall thickness in early childhood, but not adiposity or growth trajectory during the first year of life. This trial was registered at anzctr.org.au as ACTRN12610000681055.

Dietary micronutrient intake during pregnancy is a function of carbohydrate quality

BACKGROUND

Despite normal gestational weight gain, dietary studies in pregnant women show intakes below the recommendations for energy and micronutrients.

OBJECTIVE

This study compared changes in dietary intake from the second to third trimester with emphasis on energy intake and carbohydrate quality.

DESIGN

These post hoc analyses were based on 566 women participating in the Pregnancy and Glycemic Index Outcomes study, a randomized controlled trial comparing the effect of low-glycemic index (GI) dietary advice with healthy eating advice on selected pregnancy outcomes. With the use of multilevel mixed-regression analysis, changes in total energy intake, starch, sugar, fiber intake, GI, and glycemic load (GL) were correlated with intake of different micronutrients.

RESULTS

Energy intake decreased in the third trimester, and most women did not meet the national recommended amounts for iron, folate, and dietary fiber from food sources alone. After adjustment for age, ethnicity, prepregnancy body mass index, and intervention group, change in energy intake was positively related to change in intake of all micronutrients (P < 0.001). GI, GL, and starch intake were inversely related to micronutrient intake (P < 0.001), whereas higher total sugars predicted higher intake (P < 0.001). Associations with dietary fiber were inconsistent.

CONCLUSIONS

Normal pregnancy can be associated with a decline in energy and micronutrient intake from diet. Low dietary GI and GL were the best predictors of a favorable micronutrient profile. This trial was registered at www.anzctr.org.au as ACTRN12610000174088.

Dairy food consumption, blood pressure and retinal microcirculation in adolescents

BACKGROUND AND AIMS

The relationship between dairy food consumption and dietary calcium intake, and vascular risk factors during adolescence remains unclear. We aimed to prospectively assess whether dairy food consumption (milk, cheese, yoghurt) is associated with blood pressure (BP) and retinal microvascular signs among adolescents.

METHODS AND RESULTS

As many as 2353 and 1216 participants aged 12 and 17, respectively, were examined. Longitudinal analyses involved 888 subjects with complete baseline and follow-up data. Dairy consumption was assessed from validated semi-quantitative food frequency questionnaires. BP information was collected and retinal vessel caliber was quantified from digital photographs using computer software. In girls, after multivariable adjustment, each serve/day increase in total dairy intake was concurrently associated with 1.04 (p = 0.03) and 1.10 mm Hg (p = 0.02) decreases in mean diastolic and arterial BP, respectively. Also in girls, each serve/day increase in cheese intake over 5 years was concurrently related to 7.18 (p = 0.001), 5.28 (p = 0.002) and 5.79 mm Hg (p = 0.001) decrease in mean systolic, diastolic and arterial BP, respectively. Among girls, each 100 mg/day increase in dietary calcium intake was associated with a concurrent 0.5 (p = 0.01) and 0.3 mm Hg (p = 0.02) decrease in mean systolic and arterial BP, respectively. Cross-sectionally, adolescents in the highest versus lowest tertile of yoghurt intake had ∼ 1.3 μm wider retinal arterioles (p = 0.05) and ∼ 2.0 μm narrower venules (p = 0.04).

CONCLUSIONS

Consumption of dairy products, particularly cheese, could have a beneficial effect on BP, particularly among girls.

Influence of obesogenic behaviors on health-related quality of life in adolescents

We aimed to prospectively examine the association between the combined effects of obesogenic behaviors on quality of life (QOL) in adolescents. Of 2353 Sydney schoolchildren surveyed (median age 12.7 years), 1,213 were re-examined 5 years later at age 17-18. Children completed activity and food-frequency questionnaires. An unhealthy behavior score was calculated, allocating 1 point for the following: <60 minutes of total physical activity/ day; ≥2 hours of screen time/ day; consumed salty snack foods and/or confectionery ≥5 times per week; ≥1 serves of soft drinks and/or cordial/ day; and not consuming both ≥2 serves of fruit and ≥3 serves of vegetables/ day. Health-related QOL was assessed by the Pediatric Quality of Life Inventory (PedsQL). The prevalence of 0, 1, 2, 3, 4, and 5 lifestyle risk factors was 4.2%, 17.1%, 30.7%, 30.5%, 13.9% and 3.6%, respectively. After multivariable- adjustment, children engaging in 5 versus 0 unhealthy behaviors had 9.2-units lower PedsQL physical summary score (ptrend=0.001), five years later. Boys reporting 4 or 5 lifestyle risk factors compared to their peers reporting none or one at baseline, had lower total and physical summary scores at follow-up, ptrend=0.02 and 0.01, respectively. Girls engaging in 4 or 5 versus 0 or 1 unhealthy behaviors, had 4.6-units lower physical summary score (ptrend=0.04), five years later. The number of obesogenic lifestyle risk factors was independently associated with subsequent poorer QOL, particularly physical health, during adolescence. These findings underscore the importance of targeting lifestyle behaviors to promote general well-being and physical functioning in adolescents.

Parental history of hypertension and dietary intakes in early adolescent offspring: a population-based study

We investigated the cross-sectional association between parental history of hypertension and dietary intakes among early adolescent schoolchildren. A total of 1845 participants aged 12 years had complete data on diet and parental medical history, and thus they were included in the final analyses. Dietary data were assessed from validated semi-quantitative food-frequency questionnaires. Parents completed questionnaires about their medical conditions. Cases where the biological mother and/or father had hypertension were classified as positive parental history of hypertension. After multivariable adjustment, participants with positive versus negative parental history of hypertension had 33% greater likelihood of consuming soft drinks ⩾1 per week. Boys with a parental history versus boys without a parental history of hypertension consumed more energy-dense, nutrient-poor foods: 379.4 g per day and 318.0 g per day, respectively, P=0.02. Girls with a positive versus a negative parental history consumed more vegetables: 164.1 versus 142.6 g per day, P=0.01. Significant associations were not observed between those with and those without a positive parental history in mean dietary intakes of carbohydrates, fats, sugars and sodium. Children with a positive parental history of hypertension were 67% more likely to simultaneously engage in three unhealthy lifestyle behaviors (excessive recreational screen viewing, high consumption of snacks and and high consumption of soft drinks). Parental hypertension was associated with unhealthy dietary behaviors among offspring, including higher consumption of soft drinks and energy-dense, nutrient-poor foods.

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.

Do we provide meaningful guidance for healthful eating? An investigation into consumers' interpretation of frequency consumption terms

OBJECTIVE

To investigate consumers' understanding of terms commonly used to provide guidance about frequency and quantity of food consumption.

METHODS

A survey of 405 shoppers explored how frequently consumers thought food labeled with the terms "eat often," "eat moderately," "eat occasionally," "a sometimes food," and "an extra food" should be eaten. In a separate phase, 30 grocery buyers responded to open-ended questions about their interpretation of these terms.

RESULTS

Responses indicated significant differences in meaning between the terms. However, the specific interpretation of each term varied considerably across respondents. The qualitative research found the terms to be highly subjective, and there was a high degree of uncertainty about the meaning of the term "an extra food" in particular.

CONCLUSIONS AND IMPLICATIONS

Food frequency and descriptive terms currently used do not provide meaningful or consistent nutritional guidance. There is a need for simple, unambiguous terminology.

Consumer response to healthy eating, physical activity and weight-related recommendations: a systematic review

Strong evidence linking poor diet and lack of physical activity to risk of obesity and related chronic disease has supported the development and promotion of guidelines to improve population health. Still, obesity continues to escalate as a major health concern, and so the impact of weight-related guidelines on behaviour is unclear. The aim of this review was to examine consumer response to weight-related guidelines. A systematic literature search was performed using Medline, PsycInfo, ProQuest Central and additional searches using Google and reference lists. Of the 1,765 articles identified, 46 relevant titles were included. Most studies examined attitudes towards content, source, tailoring and comprehension of dietary guidelines. Many respondents reported that guidelines were confusing, and that simple, clear, specific, realistic, and in some cases, tailored guidelines are required. Recognition of guidelines did not signify understanding nor did perceived credibility of a source guarantee utilization of guidelines. There was a lack of studies assessing: the impact of guidelines on behaviour; responses to physical activity guidelines; responses among males and studies undertaken in developing countries. Further research is needed, in particular regarding responses to physical activity guidelines and guidelines in different populations. Communication professionals should assist health professionals in the development of accurate and effective weight-related guidelines.

Carbohydrate nutrition is associated with changes in the retinal vascular structure and branching pattern in children

BACKGROUND

Higher intake of carbohydrates and high-glycemic index (high-GI) diets could lead to small vessel dysfunction.

OBJECTIVES

We aimed to assess the associations between intakes of high-GI and high-glycemic load (high-GL) diets, carbohydrate, and the main carbohydrate-containing food groups and retinal microvascular changes in preadolescents.

DESIGN

Students aged 12 y (n = 2353) from a random cluster sample of 21 schools underwent detailed eye examinations. Retinal vessel caliber and fractal dimension were measured from digital retinal images. A validated semiquantitative food-frequency questionnaire was administered.

RESULTS

After multivariable adjustment, children who consumed soft drinks once or more per day had significantly narrower mean retinal arterioles (∼1.9 μm) than did those who never or rarely consumed soft drinks (P-trend = 0.03). When the highest to lowest tertiles of carbohydrate consumption were compared, girls had significantly narrower retinal arterioles (∼1.4 μm; P-trend = 0.03) and boys had wider venules (∼2.3 μm; P-trend = 0.02). In girls only, a higher-GI diet was associated with narrower retinal arterioles (0.98-μm narrowing of retinal arteriolar caliber per SD increase in GI, P = 0.01). Carbohydrate intake and a high-GL diet were associated with greater retinal fractal dimension in girls (highest compared with lowest tertiles: P-trend = 0.003 and 0.01, respectively).

CONCLUSIONS

Greater consumption of carbohydrates and soft drinks was associated with retinal arteriolar narrowing and venular widening. Because these microvascular signs have been shown to be markers of future cardiovascular disease risk, the presence of this risk factor in children could support the need for healthy dietary patterns that include lower consumption of high-GI foods and soft drinks.

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.