The influence on population weight gain and obesity of the macronutrient composition and energy density of the food supply

Rates of overweight and obesity have increased dramatically in all regions of the world over the last few decades. Almost all of the world's population now has ubiquitous access to low-cost, but highly-processed, energy-dense, nutrient-poor food products. These changes in the food supply, rather than decreases in physical activity, are most likely the primary driver of population weight gain and obesity. To-date, the majority of prevention efforts focus on personalised approaches targeting individuals. Population-wide food supply interventions addressing sodium and trans fat reduction have proven highly effective and comparable efforts are now required to target obesity. The evidence suggests that strategies focusing upon reducing the energy density and portion size of foods will be more effective than those targeting specific macronutrients. Government leadership, clearly specified targets, accountability and transparency will be the key to achieving the food supply changes required to address the global obesity epidemic.

A path model of psychosocial and health behaviour change predictors of excessive gestational weight gain

This study aimed to evaluate a conceptual model of psychosocial, behaviour change, and behavioural predictors of excessive gestational weight gain (GWG). Background: Excessive GWG can place women and their babies at risk of poor health outcomes, including obesity. Models of psychosocial and behaviour change predictors of excessive GWG have not been extensively explored; understanding the mechanisms leading to excess GWG will provide crucial evidence towards the development of effective interventions. Method: Two hundred and eighty-eight pregnant women (≤18 weeks gestation) were recruited to a prospective study. Demographic, psychosocial, health behaviour change, and behavioural factors were assessed at 17 (Time 1, T1) and 33 weeks (Time 2, T2) gestation. Pre-pregnancy and final pregnancy weight were obtained and women were classified with/without excessive GWG. Logistic regressions refined the list of predictors of excessive GWG; variables with p < .1 were included in a path analysis. Results: Age, family income, T2 depression, T2 pregnancy-specific coping, T1 buttocks dissatisfaction, T2 GWG-specific self-efficacy, T1 dietary readiness, T1 dietary importance, and T1 vegetable intake predicted excessive GWG in the logistic regressions and were included in the path model. The baseline path model demonstrated poor fit. Once statistically and theoretically plausible paths were added, adequate model fit was achieved (χ² = 21.61(9), p < .05; RMSEA = .07; CFI = .93); this revised model explained 19.5% of the variance in excessive GWG. Women with high T1 buttocks dissatisfaction were more likely to exhibit low levels of dietary readiness. Women with low dietary readiness were more likely to have a lower vegetable intake, which predicted excessive GWG. Women with higher T2 depressive symptoms were more likely to report lower GWG self-efficacy and gain excessively. Conclusion: Future behavioural GWG trials should consider combining psychosocial and health behaviour change factors to optimise GWG.

Photochromic fabrics with improved optical performance

 Photochromism is a fascinating phenomenon which has attracted much commercial interest for applications including sunglasses, optical devices such as memories and switches, and security printing. Photochromic textile is an exciting new application due to its implications for fashion and UV protection. This book explores the phenomenon of photochromism, its application in textiles and ways of improving the performance and durability of photochromic fabrics.

Nutritional intervention to prevent weight gain in patients commenced on olanzapine: a randomized controlled trial

Objective: Olanzapine is the most commonly prescribed atypical antipsychotic medication in Australia. Research reports an average weight gain of between 4.5 and 7 kg in the 3 months following its commencement. Trying to minimize this weight gain in a population with an already high prevalence of obesity, mortality and morbidity is of clinical and social importance. This randomized controlled trial investigated the impact of individual nutrition education provided by a dietitian on weight gain in the 3 and 6 months following the commencement of olanzapine.


Method: Fifty-one individuals (29 females, 22 males) who had started on olanzapine in the previous 3 months (mean length of 27 days ± 20) were recruited through Peninsula Health Psychiatric Services and were randomly assigned to either the intervention (n = 29) or the control group (n = 22). Individuals in the intervention group received six 1 hour nutrition education sessions over a 3-month period. Weight, waist circumference, body mass index (BMI) and qualitative measures of exercise levels, quality of life, health and body image were collected at baseline at 3 and 6 months.


Results: After 3 months, the control group had gained significantly more weight than the treatment group (6.0 kg vs 2.0 kg, p ≤ 0.002). Weight gain of more than 7% of initial weight occurred in 64% of the control group compared to 13% of the treatment group. The control group's BMI increased significantly more than the treatment group's (2 kg/m2vs 0.7 kg/m2, p ≤ 0.03). The treatment group reported significantly greater improvements in moderate exercise levels, quality of life, health and body image compared to the controls. At 6 months, the control group continued to show significantly more weight gain since baseline than the treatment group (9.9 kg vs 2.0 kg, p ≤ 0.013) and consequently had significantly greater increases in BMI (3.2 kg/m2vs 0.8 kg/m2, p ≤ 0.017).