Longitudinal study of Consumer Price Index (CPI) trends in core and non-core foods in Australia

Objective: This study examined trends in the price of healthy and less-healthy foods from 1989 to 2007 using the Australian Consumer Price Index (CPI).

Methods: CPI food expenditure classes were classified as 'core' or 'non-core'. Trends in the CPI were analysed to examine the rise in prices of core compared with non-core foods.

Results: On average, the CPI for core foods has risen at a slightly higher, though not statistically significant, rate than non-core foods. Furthermore, selected groupings reveal interesting patterns. 'Bread' has risen in price significantly more than 'cakes and biscuits', and 'milk' has risen in price significantly more than 'soft drinks, waters and juices'.

Conclusions and implications: This investigation of food price trends reveals notable differences between core and non-core foods. This should be investigated further to determine the extent to which this contributes to the higher prevalence of diet-related diseases in low socio-economic groups.

Understanding the oil price-exchange rate nexus for the Fiji Islands

In this paper, we examine the relationship between oil price and the Fiji–US exchange rate using daily data for the period 2000–2006. We use the generalised autoregressive conditional heteroskedasticity (GARCH) and exponential GARCH (EGARCH) models to estimate the impact of oil price on the nominal exchange rate. We find that a rise in oil prices leads to an appreciation of the Fijian dollar vis-à-vis the US dollar.

Maintenance of traditional cultural orientation is associated with lower rates of obesity and sedentary behaviours among African migrant children to Australia

Background: Migrants from developing to developed countries rapidly develop more obesity than the host population. While the effects of socio-economic status on obesity are well established, the influence of cultural factors, including acculturation, is not known.

Objective: To examine the association between acculturation and obesity and its risk factors among African migrant children in Australia.

Design and participants: A cross-sectional study using a non-probability sample of 3- to 12-year-old sub-Saharan African migrant children. A bidimensional model of strength of affiliation with African and Australian cultures was used to divide the sample into four cultural orientations: traditional (African), assimilated (Australian), integrated (both) and marginalized (neither).

Main outcome measures: Body mass index (BMI), leisure-time physical activity (PA) and sedentary behaviours (SBs) and energy density of food.

Results: In all, 18.4% (95% confidence interval (CI): 14–23%) were overweight and 8.6% (95% CI: 6–12%) were obese. After adjustment for confounders, integrated (ß=1.1; P<0.05) and marginalized ß(=1.4; P<0.01) children had higher BMI than traditional children. However, integrated children had significantly higher time engaged in both PA (ß=46.9, P<0.01) and SBs (ß=43.0, P<0.05) than their traditional counterparts. In comparison with traditional children, assimilated children were more sedentary (ß=57.5, P<0.01) while marginalization was associated with increased consumption of energy-dense foods (ß=42.0, P<0.05).

Conclusions: Maintenance of traditional orientation was associated with lower rates of obesity and SBs. Health promotion programs and frameworks need to be rooted in traditional values and habits to maintain and reinforce traditional dietary and PA habits, as well as identify the marginalized clusters and address their needs.

Identifying house price diffusion patterns among Australian state capital cities

Prior research supports the proposition that house price diffusion shows a ripple effect along the spatial dimension. That is, house price changes in one region would reflect in subsequent house price changes in other regions, showing certain linkages among regions. Using the vector autoregression model and the impulse response function, this study investigates house price diffusion among Australia's state capital cities, examining the response of one market to the innovation of other markets and determining the lagged terms for the maximum absolute value of the other markets' responses. The results show that the most important subnational markets in Australia do not point to Sydney, rather towards Canberra and Hobart, while the Darwin market plays a role of buffer. The safest markets are Sydney and Melbourne. This study helps to predict house price movement trends in eight capital cities.

The effect of training in reduced energy density eating and food self-monitoring accuracy on weight loss maintenance

Background:
Failure to maintain weight losses in lifestyle change programs continues to be a major problem and warrants investigation of innovative approaches to weight control.
Objective:
The goal of this study was to compare two novel group interventions, both aimed at improving weight loss maintenance, with a control group.
Methods and Procedures:
A total of 103 women lost weight on a meal replacement–supplemented diet and were then randomized to one of three conditions for the 14-week maintenance phase: cognitive-behavioral treatment (CBT); CBT with an enhanced food monitoring accuracy (EFMA) program; or these two interventions plus a reduced energy density eating (REDE) program. Assessments were conducted periodically through an 18-month postintervention. Outcome measures included weight and self-reported dietary intake. Data were analyzed using completers only as well as baseline-carried-forward imputation.
Results:
Participants lost an average of 7.6 plusminus 2.6 kg during the weight loss phase and 1.8 plusminus 2.3 kg during the maintenance phase. Results do not suggest that the EFMA intervention was successful in improving food monitoring accuracy. The REDE group decreased the energy density (ED) of their diets more so than the other two groups. However, neither the REDE nor the EFMA condition showed any advantage in weight loss maintenance. All groups regained weight between 6- and 18-month follow-ups.
Discussion:
Although no incremental weight maintenance benefit was observed in the EFMA or EFMA + REDE groups, the improvement in the ED of the REDE group's diet, if shown to be sustainable in future studies, could have weight maintenance benefits.

Physical activity and healthy weight maintenance from childhood to adulthood

The objective of this study was to determine whether change in physical activity was associated with maintaining a healthy weight from childhood to adulthood. This prospective cohort study examined 1,594 young Australian adults (48.9% female) aged 27–36 years who were first examined at age 9–15 years as part of a national health and fitness survey. BMI was calculated from measured height and weight, and physical activity was self-reported at both time points; pedometers were also used at follow-up. Change in physical activity was characterized by calculating the difference between baseline and follow-up z-scores. Change scores were categorized as decreasing (large, moderate), stable, or increasing (large, moderate). Healthy weight was defined in childhood as a BMI less than international overweight cutoff points, and in adulthood as BMI<25 kg/m2. Healthy weight maintainers were healthy weight at both time points. Compared with those who demonstrated large relative decreases in physical activity, females in all other groups were 25–37% more likely to be healthy weight maintainers, although associations differed according to the physical activity measure used at follow-up and few reached statistical significance. Although younger males whose relative physical activity moderately or largely increased were 27–34% more likely to be healthy weight maintainers than those whose relative physical activity largely decreased, differences were not statistically significant. In conclusion, relatively increasing and stable physical activity from childhood to adulthood was only weakly associated with healthy weight maintenance. Examining personal, social, and environmental factors associated with healthy weight maintenance will be an important next step in understanding why some groups avoid becoming overweight.

Are nominal exchange rates and price levels co-integrated? new evidence from threshold autoregressive and momentum-threshold autoregressive models

The goal of this paper is to examine evidence for co-integration between nominal exchange rates for Canada, the UK, Japan, Germany, Italy and France (G6) vis-à-vis the US dollar, and the relative price ratios using monthly data over the period 1973:01 to 1997:04. Motivated by the fact that exchange rate adjustment may be asymmetric, we allowed for asymmetric adjustment in exchange rates by using the threshold autoregressive model and the momentum threshold autoregressive model. We do not find any evidence of a co-integrating relationship; hence, we fail to establish long-run purchasing power parity.

Forecasting stock index volatility : comparing implied volatility and the intraday high-low price range

The intraday high–low price range offers volatility forecasts similarly efficient to high-quality implied volatility indexes published by the Chicago Board Options Exchange (CBOE) for four stock market indexes: S&P 500, S&P 100, NASDAQ 100, and Dow Jones Industrials. Examination of in-sample and out-of-sample volatility forecasts reveals that neither implied volatility nor intraday high–low range volatility consistently outperforms the other.

Community center-based resistance training for the maintenance of glycemic control in adults with type 2 diabetes

OBJECTIVE--The purpose of this study Was to determine whether beneficial effects on glycemic control of an initial laboratory-supervised resistance training program could be sustained through a community center-based maintenance program.

RESEARCH DESIGN AND METHODS--We studied 57 overweight (BMI [greater than or equal to] 27 kg/[m.sup.2]) sedentary men and women aged 40-80 years with established (>6 months) type 2 diabetes. Initially, all participants attended a twice-weekly 2-month supervised resistance training program conducted in the exercise laboratory. Thereafter, participants undertook a resistance training maintenance program (2 times/week) for 12 months and were randomly assigned to carry this out either in a community fitness and recreation center (center) or in their domestic environment (home). Glycemic control ([HbA.sub.1c] [A1C]) was assessed at 0, 2, and 14 months.

RESULTS--Pooling data from the two groups for the 2-month supervised resistance training program showed that compared with baseline, mean A1C fell by -0.4% [95% CI -0.6 to -0.2]. Within-group comparisons showed that A1C remained lower than baseline values at 14 months in the center group (-0.4% [-0.7 to -0.03]) but not in the home group (-0.1% [-0.4 to 0.3]). However, no between-group differences were observed at each time point. Changes in A1C during the maintenance period were positively associated with exercise adherence in the center group only.

CONCLUSIONS--Center-based but not home-based resistance training was associated with the maintenance of modestly improved glycemic control from baseline, which was proportional to program adherence. Our findings emphasize the need to develop and test behavioral methods to promote healthy lifestyles including increased physical activity in adults with type 2 diabetes.

Fowl play and the price of petrel: long-living Procellariiformes have peroxidation-resistant membrane composition compared with short-living Galliformes

The membrane pacemaker hypothesis predicts that long-living species will have more peroxidation-resistant membrane lipids than shorter living species. We tested this hypothesis by comparing the fatty acid composition of heart phospholipids from long-living Procellariiformes (petrels and albatrosses) to those of shorter living Galliformes (fowl). The seabirds were obtained from by-catch of commercial fishing operations and the fowl values from published data. The 3.8-fold greater predicted longevity of the seabirds was associated with elevated content of peroxidation-resistant monounsaturates and reduced content of peroxidation-prone polyunsaturates and, consequently, a significantly reduced peroxidation index in heart membrane lipids, compared with fowl. Peroxidation-resistant membrane composition may be an important physiological trait for longevous species.

Effects of diets high in whey, soy, red meat and milk protein on body weight maintenance in diet-induced obesity in mice

This study examined the effects of different food sources of protein on energy intake, body weight maintenance, and on the responses of plasma leptin, insulin and adiponectin in chronic high-fat diet-induced obese mice. Obesity was induced in 47 mice with a high-fat diet for 20 weeks. They were divided into five diet groups to test the effects of a higher protein proportion (30% energy), achieved at the expense of carbohydrate. For the next eight weeks, four of the groups were fed diets of chow formulated with whey, soy, red meat or milk while the control group continued on their high-fat diet. The results showed that: (i) increasing the protein : carbohydrate ratio (both at 30% energy) in a high-fat diet did not reduce the level of obesity; (ii) the type of protein added, however, did have a significant effect on the level of obesity attained; (iii) whey protein stabilised weight gain the most, had the strongest satiety effects and also stimulated the highest production of adiponectin; and (iv) whey protein also was associated with the lowest insulin values among all proteins tested. Plasma leptin levels were not affected by any of the diets. Dietary fat remains a potent factor in weight management, but the type and amount of protein may also be important through its effects on food intake. In particular, the apparent decreased appetite associated with increased adiponectin in the whey-based high-protein diet may contribute to stabilised body mass in chronic high-fat diet-induced obesity.