Vitamin D deficiency is associated with an increased risk of falls and fractures. Assuming this association is causal, we aimed to identify the number and proportion of hospitalisations for falls and hip fractures attributable to vitamin D deficiency (25 hydroxy D (25(OH)D) <50 nmol/l) in Australians aged ≥65 years. We used 25(OH)D data from the 2011/12 Australian Health Survey and relative risks from published meta-analyses to calculate population-attributable fractions for falls and hip fracture. We applied these to data published by the Australian Institute of Health and Welfare to calculate the number of events each year attributable to vitamin D deficiency. In men and women combined, 8·3 % of hospitalisations for falls (7991 events) and almost 8 % of hospitalisations for hip fractures (1315 events) were attributable to vitamin D deficiency. These findings suggest that, even in a sunny country such as Australia, vitamin D deficiency contributes to a considerable number of hospitalisations as a consequence of falls and for treatment of hip fracture in older Australians; in countries where the prevalence of vitamin D deficiency is higher, the impact will be even greater. It is important to mitigate vitamin D deficiency, but whether this should occur through supplementation or increased sun exposure needs consideration of the benefits, harms, practicalities and costs of both approaches.

The occurrence and genesis of Ca(OH)2 and Mg(OH)2 deposits associated with hyperalkaline groundwater from partly serpentinized ultramafic rocks in Northern Oman is reported. Two types of Ca(OH)2 deposit are differentiated; crystalline portlandite formed by the evaporation of Ca2+-2OH− spring waters, and a form of amorphous gel, not previously known in nature. The latter is a product of present-day low-temperature serpentinization. Mg(OH)2 (brucite) in both holocrystalline and gel forms is produced by mixing of Mg2+−2H surface waters with a Ca2+-2OH− groundwater in both surface and groundwater environments. These results indicate that significant differences exist between the processes of medium- and low-temperature brucite generation.

The chemical composition and the utilization by domestic goats (Capra hircus L. ‘Saanen’) of alfalfa (Medicago sativa L.) hay and silage that contained or did not contain hoary alyssum [Berteroa incana (L.) DC. ♯ BEFIN] was studied. Alfalfa was higher in quality than hoary alyssum; crude protein (CP) was 38% higher, and the neutral- and acid-detergent fiber (NDF and ADF) were 18 and 29% lower, respectively. Less CP and more ADF were found in weedy hay than in other forages. Animal utilization, as measured by the dry-matter intake, digestible dry-matter intake, relative intake, and nutritive value index were greater for weed-free than for weedy forages. Hoary alyssum was more deleterious in chopped silage than in long hay, because of selective refusal of the weed by goats that were fed hay. The presence of hoary alyssum in alfalfa decreased its utilization by ruminants.

We expand our previous deterministic power calculations by calculating the required sample size to detect C in ACE models. The theoretical expected value of the maximum log-likelihood for the AE model was derived using two optimisation methods and these gave near-identical results. Theoretical predictions were verified by computer simulation and the results agreed very well. We have developed a user-friendly web-based tool, TwinPower, to perform power calculations to detect either A or C for the classical twin design. This new tool can be found at http://genepi.qimr.edu.au/cgi-bin/twinpower.cgi

The cholesterol-lowering effects of plant sterols in a format suitable for use in China have not previously been investigated. We conducted the study to quantify in adult Chinese the effects on blood lipid concentrations of a plant sterol-enriched milk tea powder. The study was a double-blind, randomised trial in which 309 participants were randomised to receive daily 2·3 or 1·5 g plant sterol supplementation or placebo for 5 weeks. The milk tea was consumed with the two fattiest meals of the day with half the assigned daily dose taken on each occasion. Fasting venous blood samples were collected before commencement and upon completion of randomised treatment. The mean age of study participants was 44 years, 62 % were female and 62 % had a history of hypercholesterolaemia. Baseline mean total cholesterol was 5·5 mmol/l and LDL-cholesterol was 3·2 mmol/l. Compared with placebo, the 2·3 g/d plant sterol dose reduced total cholesterol by 0·25 (95 % CI 0·07, 0·43) mmol/l (P = 0·01) and the 1·5 g/d dose by 0·23 (95 % CI 0·06, 0·41) mmol/l (P = 0·01). For LDL-cholesterol the corresponding reductions were 0·17 (95 % CI 0·00, 0·35) mmol/l (P = 0·06) and 0·15 (95 % CI − 0·02, 0·32) mmol/l (P = 0·08). For neither outcome was there evidence of differences between the effects of the two doses (both P values >0·4). In conclusion, the consumption of plant sterol-enriched milk tea decreased cholesterol concentrations although to a lesser extent than was anticipated. The reason for reduced efficacy is unclear but may be attributable to the novel food format used or the Chinese population studied.