Amanda Grech

A systematic literature review of nutrition interventions in vending machines that encourage consumers to make healthier choices

Internationally, vending machines are scrutinized for selling energy‐dense nutrient‐poor foods and beverages, and the contribution to overconsumption and subsequent risk of obesity. The aim of this review is to determine the efficacy of nutrition interventions in vending machine in eliciting behaviour change to improve diet quality or weight status of consumers. Electronic databases Cochrane, EMBASE, CINAHL, Science Direct and PubMed were searched from inception. Inclusion criteria: (i) populations that have access to vending machines; (ii) nutrition interventions; (iii) measured outcomes of behaviour change (e.g. sales data, dietary intake or weight change); and (iv) experimental trials where controls were not exposed to the intervention. Risk of bias was assessed independently by two researchers, and higher quality research formed the basis of this qualitative review. Twelve articles from 136 searched were included for synthesis. Intervention settings included schools, universities and workplaces. Reducing price or increasing the availability increased sales of healthier choices. The results of point‐of‐purchase nutrition information interventions were heterogeneous and when measured changes to purchases were small. This review offers evidence that pricing and availability strategies are effective at improving the nutritional quality foods and beverages purchased from vending machines. Evidence on how these interventions alter consumers overall diet or body mass index is needed.

Socio-Demographic Determinants of Diet Quality in Australian Adults Using the Validated Healthy Eating Index for Australian Adults (HEIFA-2013)

Diet quality indices have been shown to predict cardiovascular disease, cancer, Type 2 Diabetes, obesity and all-cause mortality. This study aimed to determine the socio-demographics of Australian adults with poor diet quality. Diet quality was assessed for participants of the 2011–2012 National Nutrition and Physical Activity Survey aged 18 years or above (n = 9435), with the validated 11-component Healthy Eating Index for Australians (HEIFA-2013), based on the 2013 Australian Dietary Guidelines. Differences in scores by demographics (ANOVA) and regression models for associations between the HEIFA-2013 score and demographic characteristics were conducted. The mean (SD) HEIFA-2013 score was 45.5 (14.7) out of 100 due to poor intakes of vegetables, fruit, grains, dairy and fat and high intakes of added sugar, sodium and discretionary foods. Lower mean HEIFA-2013 scores (SD) were found for males 43.3 (14.7), young-adults 41.6 (14.2) obese 44.1 (14.3), smokers 40.0 (14.2), low socio-economic status 43.7 (14.9) and Australian country-of-birth 44.2 (14.6) (p < 0.05). The overall diet quality of the Australian population is poor and targeted interventions for young-adults, males, obese and those with lower socio-economic status are recommended.

Prevalence and period trends of overweight and obesity in Australian young adults

This analysis examines period trends in body weight of Australian 18–24 year olds. Secondary analysis of National Health Surveys was performed, including examination of socio-demographic determinants of obesity. The prevalence of overweight and obesity has increased from 24.0 and 5.1% in males and 13.2 and 5.8% in females, respectively, in 1995 to 29.3 and 13.8% in males and 20.6 and 20.6% in females in 2012. Mean body mass index (BMI) increased over time from 23.7 (s.d. 3.5) for males and 22.4 (s.d. 4.0) for females in 1995 to 25.2 (s.d. 4.8) and 25.5 (s.d. 5.9) in 2011/2. Lower educational attainment increased the odds of having BMI⩾25.00 kg/m2 for both sexes (P=0.03 males and P<0.001 females). Overweight and obesity were higher in rural females (P<0.05) and those socio-economically disadvantaged (P<0.0001). The obesity epidemic has worsened for Australian young adults and in particular young females.

The fruit and vegetable intake of young Australian adults: a population perspective

OBJECTIVE To examine intakes and variety of fruit and vegetables consumed by Australian young adults, also assessing differences by meal occasion and sociodemographic characteristics. DESIGN Secondary analysis of cross-sectional 24 h recall data collected through the 2011-12 National Nutrition and Physical Activity Survey. Crude means and proportions consuming fruits and vegetables were calculated. Pearson χ 2 tests, Kruskal-Wallis analyses and linear regression models were used to assess differences in mean intakes by age, BMI and sociodemographic variables. The variety eaten was determined based on the number of fruit and vegetable subgroups consumed. SETTING Representative sample of metropolitan and rural areas across Australia. SUBJECTS Respondents aged 18-34 years were included (n 2397). RESULTS Mean daily intake of fruit (128 g/0·9 servings) and vegetables (205 g/2·7 servings) was lower than the minimum recommended intake set at 2 and 5 servings, respectively. Age was positively associated with fruit and vegetable intake (P=0·002, P<0·001), with 18-24-year-olds reporting the poorest vegetable variety compared with 25-29- and 30-34-year-olds (P=0·002). When controlling for total energy, males consumed less vegetables than females (P=0·002). A large proportion of the 15 % of respondents who consumed adequate amounts of fruits and vegetables on the day prior to the survey reported intake across all meal occasions (P<0·001). CONCLUSIONS Fruit and vegetable intake is suboptimal among Australian young adults. An age-appropriate campaign is recommended to target increased consumption, particularly for those aged 18-24 years, with opportunity to promote increased variety and consumption across the day.

Are products sold in university vending machines nutritionally poor? A food environment audit

AIM (i) To audit the nutritional composition, promotion and cost of products available from vending machines available to young adults; and (ii) to examine the relationship between product availability and sales. METHODS A cross-sectional analysis of snacks and beverages available and purchased at a large urban university was conducted between March and September 2014. Sales were electronically tracked for nine months. RESULTS A total of 61 vending machines were identified; 95% (n = 864) of the available snacks and 49% of beverages (n = 455) were less-healthy items. The mean (SD) nutrient value of snacks sold was: energy 1173 kJ (437.5), saturated fat 5.36 g (3.6), sodium 251 mg (219), fibre 1.56 g (1.29) and energy density 20.16 kJ/g (2.34) per portion vended. There was a strong correlation between the availability of food and beverages and purchases (R2 = 0.98, P < 0.001). CONCLUSIONS Vending machines market and sell less-healthy food and beverages to university students. Efforts to improve the nutritional quality are indicated and afford an opportunity to improve the diet quality of young adults, a group at risk of obesity.

Social Determinants and Poor Diet Quality of Energy-Dense Diets of Australian Young Adults

This research aimed to determine the diet quality and socio-demographic determinants by level of energy-density of diets of Australian young adults. Secondary analysis of the Australian National Nutrition and Physical Activity Survey-2011/2012 for adults aged 18–34 years (n = 2397) was conducted. Diet was assessed by 24-h recalls. Dietary energy-density was calculated as dietary energy/grams of food (kJ/g) and the Healthy-Eating-Index-for-Australians (HEIFA-2013) was used to assess diet quality (highest score = 100). Dietary energy-density was examined with respect to diet quality and sociodemographic determinants including gender, highest tertiary-education attainment, country-of-birth, age, income, and socio-economic-index-for-area (SEIFA). Higher dietary energy-density was associated with lower diet quality scores (β = −3.71, t (2394) = −29.29, p < 0.0001) and included fewer fruits and vegetables, and more discretionary foods. The mean dietary energy-density was 7.7 kJ/g and 7.2 kJ/g for men and women, respectively. Subpopulations most at risk of consuming high energy-dense diets included those with lower education, Australian and English-speaking countries of birth, and men with low income and women from areas of lower socio-economic status. Young adults reporting low energy-dense diets had higher quality diets. Intensive efforts are needed to reduce the high energy-density of young adults’ diets, and should ensure they include populations of lower socio-economic status.

Assessing the efficacy and external validity of interventions promoting calcium or dairy intake in young adults: A systematic review with meta-analysis

ABSTRACT Calcium and dairy products have a role in the prevention of chronic diseases and attainment of peak bone mass, during adolescence to young adulthood. However, intakes are often suboptimal and interventions to improve consumption of food sources are needed. This systematic review aimed to investigate the efficacy and external validity of interventions promoting calcium or dairy foods among young adults. Eight databases were searched from inception to identify relevant studies. Inclusion criteria included those aged 18 to 35 years in an intervention promoting calcium or dairy food intake. The mean age of the participants was 19.9 ± 1.4 years. Of the 16 studies that met the selection criteria, five studies were included in the meta-analyses for calcium (pooled effect size 0.35, 95% CI 0.04 to 0.67) and three studies for dairy (pooled effect size 0.31, 95% CI 0.11 to 0.50). The quality of the body of evidence was determined using the GRADE system, and was of overall low quality with high risk of bias. Our review suggests young adults respond favorably to interventions but the effect size is small.

Effectiveness of lifestyle interventions for preventing harmful weight gain among young adults from lower socioeconomic status and ethnically diverse backgrounds: a systematic review

The incidence of overweight and obesity are increasing with each successive generation of young adults. Associated co‐morbidities will emerge at an earlier age unless weight gain is prevented. Evidence has demonstrated young adults (aged 18–35 years) from low socioeconomic and ethnically diverse backgrounds are at greater risk of overweight or obesity, yet it is unclear how to effectively intervene in this population. This systematic review aimed to assess the effectiveness of lifestyle interventions conducted in this population. Thirty studies reporting on lifestyle interventions for prevention of weight gain were identified from eight electronic databases searched. Six interventions included subgroup analyses to determine if ethnicity moderated weight change, and two included subgroup analyses to determine if socioeconomic status had an effect on change in weight. Five of these six studies were effective in preventing weight gain, and subgroup analyses showed no differences in effect by ethnicity. Of these five studies, two included a subgroup analysis that showed socioeconomic status to have no effect on weight outcome. Despite the promising results from these five lifestyle interventions utilizing online and mobile components to effectively reach and prevent weight gain in this priority population, the evidence base of high quality trials is limited.

Low calcium intakes among Australian adolescents and young adults are associated with higher consumption of discretionary foods and beverages

OBJECTIVES Calcium is an essential nutrient required for peak bone mass growth during adolescence and into young adulthood. The aim of this study was to examine the calcium intake of Australian adolescents and young adults from both food sources and supplements; and the relationship between calcium intake and intake of food groups. METHODS Dietary data from 770 adolescents (14-18 y of age) and 774 young adults (19-25 y of age) from the 2011 to 12 National Nutrition and Physical Activity Survey were used. Analysis of covariances were conducted to identify associations between calcium intake and consumption of food groups. RESULTS For adolescents, 83% of males and 95% of females did not meet the Estimated Average Requirement (EAR); whereas for young adults, 69% of males and 83% of females failed to meet the EAR. Food sources contributing to calcium intake were similar across age groups and sex. The largest contributors included regular milk (15-24%), cheese (10-12%), refined low-fiber bread (10%), and low-fat milk (7-9%). For both age groups, the lowest consumers of calcium were the poorest consumers of dairy products and the highest consumers of discretionary food choices and alcoholic beverages. A higher consumption of calcium was associated with a higher intake of dairy products and lower intakes of meat and alternatives and all discretionary choices. CONCLUSIONS Calcium intake among Australian adolescents and young adults remains below recommendations, particularly in females. A higher intake of calcium was associated with a better dietary pattern. Further investment in interventions is indicated.

Diet-Quality and Socio-Demographic Factors Associated with Non-Nutritive Sweetener Use in the Australian Population

Non-nutritive sweeteners (NNS) are used in the food supply to replace sugar and/or to reduce dietary energy intake. The aim of this research was to assess the consumption prevalence and food sources of NNS in the Australian population. Food group and nutrient intakes were assessed to compare diet quality of NNS consumers and non-consumers. Secondary analysis of the Australian National Nutrition and Physical Activity Survey, 2011/12 was conducted (n = 12,435) after identifying all NNS products consumed in the population. The proportion of participants that reported intake of NNS per day was 18.2% for adults (19+ years), and 8.5% for children (2–18 years), with the most common food sources being carbonated soft drinks, tabletop sweeteners, and yoghurt. Characteristics associated with NNS consumption in adults included being female, higher body mass index (BMI), self-reported diabetes status, and being on a weight-loss diet. For adults, NNS consumers had lower free sugar intake but energy intake did not differ from non-consumers. However, for children, no differences in free sugar or energy intake were observed between consumers and non-consumers. While these results support the use of NNS in reducing sugar intake, these data suggest compensatory increases in energy intake may occur.