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.

Maternal dietary creatine supplementation does not alter the capacity for creatine synthesis in the newborn spiny mouse

We have previously reported that maternal creatine supplementation protects the neonate from hypoxic injury. Here, we investigated whether maternal creatine supplementation altered expression of the creatine synthesis enzymes (arginine:glycine amidinotransferase [AGAT], guanidinoaceteate methyltransferase [GAMT]) and the creatine transporter (solute carrier family 6 [neurotransmitter transporter, creatine] member 8: SLC6A8) in the term offspring. Pregnant spiny mice were fed a 5% creatine monohydrate diet from midgestation (day 20) to term (39 days). Placentas and neonatal kidney, liver, heart, and brain collected at 24 hours of age underwent quantitative polymerase chain reaction and Western blot analysis. Maternal creatine had no effect on the expression of AGAT and GAMT in neonatal kidney and liver, but mRNA expression of AGAT in brain tissues was significantly decreased in both male and female neonates born to mothers who were fed the creatine diet. SLC6A8 expression was not affected by maternal dietary creatine loading in any tissues. Maternal dietary creatine supplementation from midgestation in the spiny mouse did not alter the capacity for creatine synthesis or transport.

Iron status and dietary iron intake of female blood donors

Background
The aim was to assess iron status and dietary iron intake in a sample of premenopausal female regular and new blood donors.

Study design and methods
Premenopausal women blood donors were invited to participate. Blood samples were analyzed for serum ferritin and hemoglobin. An iron checklist assessed dietary iron intake. Donors were classified as regular donors or new donors.

Results
Twenty-one new donors (mean [SD] age, 28.6 [6.0] years; body mass index [BMI], 25.6 [4.5] kg/m2) and 172 regular donors (mean age, 29.4 [5.5] years; BMI, 24.7 [3.8] kg/m2) participated. Fifty percent of regular donors and 24% of new donors had depleted iron stores (serum ferritin <15 mg/L; difference p = 0.036). Dietary iron intake was higher in regular donors (mean [SE], 12.6 [0.7] mg/day) compared to new donors (9.9 [0.4] mg/day; p = 0.006). Eighty-five percent of regular donors and 79% of new donors met the estimated average requirement for iron.

Conclusions
Despite the fact that most of these donors had an adequate dietary iron intake, more than half of the blood donors had depleted iron stores. Increasing dietary iron intake through supplements and/or dietary means is expected to be necessary to maintain adequate iron status in this group.

Self-regulation and the intention behaviour gap. Exploring dietary behaviours in university students

The aim of this study was to explore whether two aspects of self-regulation (impulsivity and temporal orientation) could reduce the intention–behaviour gap for two dietary behaviours: fruit and vegetable consumption and saturated fat consumption. Australian undergraduate students (N = 154) completed questionnaires (the Barratt impulsiveness scale and the consideration of future consequences scale) and intention measures, and 1 week later behaviour was measured using the Block rapid food screener. After controlling for demographics, intention was associated with fruit and vegetable consumption, but the self-regulation measures did not further improve the variance accounted for. For saturated fat, gender was associated with consumption, such that males tended to consume more saturated fat. Intention was significantly associated with consumption, and impulsivity further improved the model such that those who were more impulsive tended to consume more saturated fat. These findings suggest that health protective and health risk behaviours, such as those investigated in the current study, may have different determinants.

n-3 LC-PUFA deposition efficiency and appetite regulating hormones are modulated by the dietary lipid source during rainbow trout grow-out and finishing periods

Largely attributable to concerns surrounding sustainability, the utilisation of omega-3 long-chain polyunsaturated fatty acid-rich (n-3 LC-PUFA) fish oils in aquafeeds for farmed fish species is an increasingly concerning issue. Therefore, strategies to maximise the deposition efficiency of these key health beneficial fatty acids are being investigated. The present study examined the effects of four vegetable-based dietary lipid sources (linseed, olive, palm and sunflower oil) on the deposition efficiency of n-3 LC-PUFA and the circulating blood plasma concentrations of the appetite-regulating hormones, leptin and ghrelin, during the grow-out and finishing phases in rainbow trout culture. Minimal detrimental effects were noted in fish performance; however, major modifications were apparent in tissue fatty acid compositions, which generally reflected that of the diet. These modifications diminished somewhat following the fish oil finishing phase, but longer-lasting effects remained evident. The fatty acid composition of the alternative oils was demonstrated to have a modulatory effect on the deposition efficiency of n-3 LC-PUFA and on the key endocrine hormones involved in appetite regulation, growth and feed intake during both the grow-out and finishing phases. In particular, n-6 PUFA (sunflower oil diet) appeared to ‘spare’ the catabolism of n-3 LC-PUFA and, as such, resulted in the highest retention of these fatty acids, ultimately highlighting new nutritional approaches to maximise the maintenance of the qualitative benefits of fish oils when they are used in feeds for aquaculture species.

A cluster-randomised, controlled trial to assess the impact of a workplace osteoporosis prevention intervention on the dietary and physical activity behaviours of working women: study protocol

Background Osteoporosis is a debilitating disease and its risk can be reduced through adequate calcium consumption and physical activity. This protocol paper describes a workplace-based intervention targeting behaviour change in premenopausal women working in sedentary occupations. Method/Design A cluster-randomised design was used, comparing the efficacy of a tailored intervention to standard care. Workplaces were the clusters and units of randomisation and intervention. Sample size calculations incorporated the cluster design. Final number of clusters was determined to be 16, based on a cluster size of 20 and calcium intake parameters (effect size 250 mg, ICC 0.5 and standard deviation 290 mg) as it required the highest number of clusters. Sixteen workplaces were recruited from a pool of 97 workplaces and randomly assigned to intervention and control arms (eight in each). Women meeting specified inclusion criteria were then recruited to participate. Workplaces in the intervention arm received three participatory workshops and organisation wide educational activities. Workplaces in the control/standard care arm received print resources. Intervention workshops were guided by self-efficacy theory and included participatory activities such as goal setting, problem solving, local food sampling, exercise trials, group discussion and behaviour feedback. Outcomes measures were calcium intake (milligrams/day) and physical activity level (duration: minutes/week), measured at baseline, four weeks and six months post intervention. Discussion This study addresses the current lack of evidence for behaviour change interventions focussing on osteoporosis prevention. It addresses missed opportunities of using workplaces as a platform to target high-risk individuals with sedentary occupations. The intervention was designed to modify behaviour levels to bring about risk reduction. It is the first to address dietary and physical activity components each with unique intervention strategies in the context of osteoporosis prevention. The intervention used locally relevant behavioural strategies previously shown to support good outcomes in other countries. The combination of these elements have not been incorporated in similar studies in the past, supporting the study hypothesis that the intervention will be more efficacious than standard practice in osteoporosis prevention through improvements in calcium intake and physical activity.

Dietary salt intake in Australian and US children and adolescents

Dietary salt intake in Australian children exceeds recommendations and children of lower socioeconomic background consume even greater quantities. In Australian and US children, salt intake was positively associated with sugar-sweetened beverages, indicating a potential link between salt intake and obesity. Public health strategies to reduce salt intake in Australian children are required.

Family food involvement and frequency of famiy dinner meals among Australian children aged 10-12 years. Cross-sectional and longitudinal associations with dietary patterns

Involvement in meal preparation and eating meals with the family are associated with better dietary patterns in adolescents, however little research has included older children or longitudinal study designs. This 3-year longitudinal study examines cross-sectional and longitudinal associations between family food involvement, family dinner meal frequency and dietary patterns during late childhood. Questionnaires were completed by parents of 188 children from Greater Melbourne, Australia at baseline in 2002 (mean age = 11.25 years) and at follow-up in 2006 (mean age = 14.16 years). Principal components analysis (PCA) was used to identify dietary patterns. Factor analysis (FA) was used to determine the principal factors from six indicators of family food involvement. Multiple linear regression models were used to predict the dietary patterns of children and adolescents at baseline and at follow-up, 3 years later, from baseline indicators of family food involvement and frequency of family dinner meals. PCA revealed two dietary patterns, labeled a healthful pattern and an energy-dense pattern. FA revealed one factor for family food involvement. Cross-sectionally among boys, family food involvement score (β = 0.55, 95% CI: 0.02, 1.07) and eating family dinner meals daily (β = 1.11, 95% CI: 0.27, 1.96) during late childhood were positively associated with the healthful pattern. Eating family dinner meals daily was inversely associated with the energy-dense pattern, cross-sectionally among boys (β = −0.56, 95% CI: −1.06, −0.06). No significant cross-sectional associations were found among girls and no significant longitudinal associations were found for either gender. Involvement in family food and eating dinner with the family during late childhood may have a positive influence on dietary patterns of boys. No evidence was found to suggest the effects on dietary patterns persist into adolescence.