Claire Margerison

Influence of dietary modifications on the blood pressure response to antihypertensive medication

Identifying dietary modifications that potentiate the blood pressure (BP)-lowering effects of antihypertensive medications and that are practical for free-living people may assist in achieving BP reduction goals. We assessed whether two dietary patterns were effective in lowering BP in persons on antihypertensive therapy and in those not on therapy. Ninety-four participants (38/56 females/males), aged 55·6 (SD 9·9) years, consumed two 4-week dietary regimens in random order (Dietary Approaches to Stop Hypertension (DASH)-type diet and low- Na high-K (LNAHK) diet) with a control diet before each phase. Seated home BP was measured daily for the last 2 weeks in each phase. Participants were grouped based on antihypertensive drug therapy. The LNAHK diet produced a greater fall in systolic BP (SBP) in those on antihypertensive therapy (-6·2 (SD 6·0) mmHg) than in those not on antihypertensive therapy (-2·8 (SD 4·0) mmHg) (P = 0·036), and this was greatest for those on renin-angiotensin system (RAS) blocker therapy (-9·5 (SD 6·4) mmHg) (interaction P = 0·007). The fall in SBP on the DASH-type diet, in those on therapy (overall -1·1 (SD 6·2) mmHg; renin-angiotensin blocker therapy -4·2 (SD 4·7) mmHg), was not as marked as that observed on the LNAHK diet. Dietary modifications are an important part of all hypertension management regimens, and a low-Na and high-K diet enhances the BP-lowering effect of antihypertensive medications, particularly those targeting the RAS.

Association of Birth Weight and Current Body Size to Blood Pressure in Female Twins

It has been proposed that low birth weight is associated with high levels of blood pressure in later life. The aim of this study was to assess the relationship of blood pressure to birth weight and current body size during growth and adulthood. A total of 711 female multiple births, with one group of 244 in their growth phase mean age 12.0 (2.3)(SD) years and the other of 467 adults (mean age 35.2 (12.6) years), had height, weight and both systolic (SBP) and diastolic (DBP) blood pressures measured, and self-reported their birth weight. Regression analyses were performed to assess the cross-sectional and within-pair associations of blood pressure to birth weight, with and without adjustments for current body size. Within-pair analysis was based on 296 twin pairs. Cross-sectionally, a reduction in birth weight of 1 kg was associated with 2 to 3 mm Hg higher age-adjusted SBP, which was of marginal significance and explained about 2% of the population variance. Adjustment for body mass index did not significantly change this association. Within-pair analyses found no association between birth weight and SBP or DBP,even after adjusting for current body size. After age, current body size was the strongest predictor of systolic BP. The weak association of blood pressure to birth weight cross-sectionally is of interest, but any within-pair effect of birth weight on blood pressure must be minimal compared with the effect of current body size.

Dietary sources and meal distribution of sodium and potassium in a sample of Australian adults

Aim Reducing dietary sodium and increasing dietary potassium are recommended to reduce blood pressure. This study aimed to determine the main foods sources of sodium and potassium. Methods Participants were recruited via advertisements or blood pressure screening sessions. Food sources of sodium and potassium were assessed via 24-hour dietary records in 299 free-living Australian adults (141 male, 158 female; age 54.6(9.5)years; BMI 29.4(3.9)kg/m2). Results The mean sodium intake was 118(51)mmol/d (2725(1176)mg/d) and the mean potassium intake was 91(28)mmol/d (3550(1098)mg/d). Breads and cereals provided the majority (38%) of sodium with bread contributing 20%. Vegetable products/dishes contributed most potassium (23%) with potatoes providing 9%. Main meals provided 89% of sodium and 85% of potassium. Lunch and dinner provided similar sodium proportions (34% and 38%, respectively) but more energy was consumed at dinner (26% vs 40%, respectively). Lunch had the highest sodium density of all meals (420 mg/MJ). Conclusion A reduction in the salt content of processed foods, particularly bread, is recommended to decrease sodium intake. This reduction in salt content combined with meal specific education focusing on choosing lower sodium foods at lunch in particular, as well as incorporating more fruits and vegetables, could effectively reduce dietary sodium and increase potassium.

Salt consumption by Australian adults: a systematic review and meta-analysis

Objective: Salt reduction is a public health priority because it is a leading contributor to the global burden of disease. As in Australia there is uncertainty about the current level of salt intake, we sought to estimate current levels.

Importance of food literacy education for senior secondary school students: food system professionals’ opinions

Abstract Food literacy education at senior secondary school could provide immediate health benefits to adolescents. In the long term, this will help strengthen the relationship between citizens and the food system. The aim of this paper is to explore food system professionals’ opinions of the importance of senior secondary school food literacy education. A purposive sample of 34 food system professionals from different sub-sectors within the Australian food system were interviewed individually in late 2015 and early 2016. Interviews were analysed using the template analysis technique. Many participants indicated that food literacy education helps students establish healthier eating patterns. Some participants suggested that food literacy education helps students join in food-related career pathways and some believed that this education helps students understand and question the food system and related issues. Moreover, some participants mentioned that the senior secondary school years are when it is most appropriate to deliver some of the broad aspects of food literacy, while some pointed out the importance of starting food literacy education in primary school. Furthermore, participants indicated the importance of food literacy education in school, referring to low food and nutrition knowledge and skills among modern consumers and inadequate family support for students to develop healthier food patterns. In conclusion, senior secondary school food literacy education helps students develop healthy eating patterns, and prepare them to make wise decisions in relation to food. This highlights the importance of provision of comprehensive food literacy education for senior secondary school students.

Food professionals’ opinions of the Food Studies curriculum in Australia

Purpose The purpose of this paper is to investigate the food system professionals’ opinions of a new senior secondary school food literacy curriculum named Victorian Certificate of Education Food Studies in Victoria, Australia. Design/methodology/approach A purposive sample of 34 food system professionals from different sub-sectors within the Australian food system was interviewed individually in late 2015 and early 2016. Interviews were analysed using the template analysis technique. Findings Most participants appreciated the extensive coverage of food literacy aspects in this new curriculum. However, many suggested amendments to the curriculum including pay less emphasis on food history-related topics and pay more focus on primary food production, nutrition awareness and promotion, and food security, food sovereignty, social justice, and food politics. Practical implications A well-structured, comprehensive secondary school food literacy curriculum could play a crucial role in providing food literacy education for adolescents. This will help them to establish healthy food patterns and become responsible food citizens. The findings of this study can be used to modify the new curriculum to make it a more comprehensive, logical, and feasible curriculum. Moreover, these findings could be used to inform the design of new secondary school food literacy curricula in Australia and other countries. Originality/value The exploration of perspectives of professionals from a broad range of food- and nutrition-related areas about school food literacy education makes this study unique. This study highlights the importance of food professionals’ opinions in secondary school food-related curricula development.

Hormone replacement therapy and bone mineral density: a co-twin approach.

ObjectiveOur objective was to estimate the difference in bone mass at clinically relevant sites within female twin pairs who were discordant for use of hormone replacement therapy (HRT). MethodsWe studied 46 female twin pairs who were discordant for HRT use. Bone mineral content and density were measured at the lumbar spine, total hip, femoral neck, 13total forearm, and the total body. HRT use, calcium intake, physical activity, alcohol intake, and lifetime smoking were determined by questionnaire. ResultsWithin a pair, lumbar spine bone mineral density was significantly greater in past and current HRT users compared with nonusers (6.2% ± 2.0%;P = 0.006). In those pairs who were currently using HRT, the within-pair difference in lumbar spine bone density was 7.8% ± 2.1% (P = 0.002), and a significant within-pair difference in forearm bone density (5.1 ± 2.1%;P = 0.02) was apparent. A significant difference (4.6%;P = 0.03) was observed in total body bone mineral content when an adjustment was made for age, lean mass, fat mass, and height. ConclusionsIn keeping with randomized clinical trial findings, these results indicate that HRT in routine clinical use protects significantly against menopausal bone loss at the lumbar spine and the forearm. Our results also quantify the magnitude of the benefit of HRT on bone density that might be anticipated in clinical practice.

Knowledge and Attitudes Are Related to Selected Salt-Specific Behaviours among Australian Parents

Salt intake in adults and children exceeds recommended levels. Salt-related knowledge, attitudes, and behaviours (KABs) may influence the amount of salt consumed. The aims of this study were to assess salt-related KABs among parents, and investigate whether salt-related knowledge and attitudes are associated with salt-specific behaviours. Parents with children <18 years were recruited from four shopping centers across Victoria, Australia; Facebook; and an online consumer research panel; they then completed an online questionnaire assessing salt-related KABs and salt use in children. Eight hundred and thirty-seven parents (mean age 41.0 (10.0) (SD) years) provided valid responses. Most (77%) parents were aware that eating too much salt damages children’s health and that reducing the amount of salt in their children’s diet was important (70%), and 46% reported adding salt to food prepared for their children. Parents who were aware that eating too much salt damages children’s health were less likely to report that their child added salt at the table (OR = 0.51, p < 0.001), and that they added salt to food prepared for the child (OR = 0.46, p < 0.001). Educational messages that highlight the adverse health effects of salt during childhood are likely to be useful in reducing discretionary salt use in the home environment.

Teachers’ perspectives of a new food literacy curriculum in Australia

Purpose Implementation of a new food literacy curriculum provides multiple health and social benefits to school students. The success of any new curriculum execution is partly determined by teachers’ perceptions about the new curriculum contents, and barriers and challenges for its delivery. The purpose of this paper is to explore teachers’ views of a new food literacy curriculum named Victorian Certificate of Education Food Studies for senior secondary school students in Victoria, Australia. Design/methodology/approach A qualitative study design was used in this study. In total, 14 teachers who were planning to teach the new curriculum were individually interviewed in October-December 2016. The interviews were transcribed and analysed using the template analysis technique. Findings The majority of teachers appreciated the inclusion of food literacy and nutrition concepts in the new curriculum. However, half of the teachers had doubts about their readiness to teach it. Most teachers mentioned that they needed more training and resources to increase their confidence in teaching the curriculum. Practical implications These findings reveal that teachers need more awareness, resources, and guidance to increase their confidence in delivering the new curriculum. Provision of more resources and opportunities for training in food literacy concepts and instructional methods could facilitate its implementation. Originality/value These findings serve as an important first step to gain the perspectives of secondary school teachers’ opinions about the new curriculum. Moreover, these opinions and suggestions could inform the future design and implementation of similar food literacy curricula in Australia or elsewhere.

Iodine Intakes of Victorian Schoolchildren Measured Using 24-h Urinary Iodine Excretion

Mandatory fortification of bread with iodized salt was introduced in Australia in 2009, and studies using spot urine collections conducted post fortification indicate that Australian schoolchildren are now replete. However an accurate estimate of daily iodine intake utilizing 24-h urinary iodine excretion (UIE μg/day) has not been reported and compared to the estimated average requirement (EAR). This study aimed to assess daily total iodine intake and status of a sample of primary schoolchildren using 24-h urine samples. Victorian primary school children provided 24-h urine samples between 2011 and 2013, from which urinary iodine concentration (UIC, μg/L) and total iodine excretion (UIE, μg/day) as an estimate of intake was determined. Valid 24-h urine samples were provided by 650 children, mean (SD) age 9.3 (1.8) years (n = 359 boys). The mean UIE of 4–8 and 9–13 year olds was 94 (48) and 111 (57) μg/24-h, respectively, with 29% and 26% having a UIE below the age-specific EAR. The median (IQR) UIC was 124 (83,172) μg/L, with 36% of participants having a UIC < 100 μg/L. This convenience sample of Victorian schoolchildren were found to be iodine replete, based on UIC and estimated iodine intakes derived from 24-h urine collections, confirming the findings of the Australian Health Survey.