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The waist-to-height ratio (wtHR) has been proposed as an alternative to body mass index (BMI) as a simple anthropometric measure of body fatness. Both measures retain residual correlations with height, which causes them to over- or under-adjust for height (and thus misestimate nutritional state) when relating these measures to chronic disease risk, morbidity or mortality. The possibility that BMI has greater misadjustment than wtHR relative to waist/height (p) and weight/height (p) (where p is the optimal exponent for each population and sex group) is examined here. Analysis of anthropometric data for groups in Thailand, Papua New Guinea and Australia shows that this is the case, especially over-adjustment. This may contribute to the weaker relationships of chronic disease markers and outcomes with BMI than with wtHR.

Three commonly consumed Indian rice varieties (Sona Masuri, Ponni and Surti Kolam) were tested for their glycaemic index (GI). Healthy volunteers were recruited and after an overnight fast were given a 50 g available carbohydrate portion of glucose (reference food) or different varieties of cooked rice (test foods) on separate occasions. The fasting as well as postprandial capillary blood glucose response was determined over 2 h, and the incremental area under the curve (IAUC) was calculated. The GI was calculated as the IAUC of the test food/IAUC of the reference food (glucose) × 100. The differences between the GI values for Sona Masuri (72.0 ± 4.5), Ponni (70.2 ± 3.6) and Surti Kolam (77.0 ± 4.0) rice varieties were non-significant (p = 0.606) and are all classified as high GI varieties of rice. There is an urgent need to study the GI of other commonly consumed rice varieties and to develop rice of a lower GI value.

Spaghetti is a favoured carbohydrate source because of its low glycaemic impact. The protein quality of semolina spaghetti is not ideal, however, and could be improved by including legume flour. We investigated whether incorporating legume flour in spaghetti, to improve its nutritional value, would affect its cooking quality and glycaemic impact. Four types of spaghetti containing 10% of either mung bean, soya bean, red lentil or chickpea flour were made and compared with a spaghetti control made only of durum semolina. Cooking quality was determined as the optimal cooking time (OCT), cooking loss (CL), dry matter (DM), swelling index, colour, hardness and adhesiveness. The spaghetti samples with legume flour were similar to one another and to the control in values of OCT, DM, swelling index, colour, CL, hardness and adhesiveness. Glycaemic impact of the samples was measured in vitro as release of rapidly available carbohydrate and slowly available carbohydrate during pancreatic digestion. The glycaemic index (GI) of the spaghetti samples was estimated by calculation, using data obtained for a reference food of known GI (shredded wheat horizontal line an extrusion-cooked wheat-only product). The shredded wheat underwent rapid parabolic digestion, and the near linear phase during which most of the starch was digested was completed between 20 and 60 min digestion. In contrast, the digestion of spaghetti was much slower and progressed almost linearly to completion. All spaghetti samples, moreover, were similarly susceptible to digestion, and compared with the wheat reference were all significantly lower in terms of relative glycaemic impact. We conclude that the incorporation of 10% legume flour in spaghetti to improve its nutritional value does not affect its cooking quality or increase its glycaemic impact.

This study was conducted to examine how subjects modulate their food intake and energy balance when they migrate from a low energy density food intake pattern to one of high energy density. It was hypothesised that an increase in the energy density of food consumed would result in increased body weight of the migrating subjects unless food intake and energy balance could be modulated. Food selection, food intake, basal metabolic rate (BMR) and anthropometric measurements were made on 53 female and 56 male newly arrived overseas students. All subjects were from Malaysia, but the data was collected at Oxford Brookes University where the subjects were studying. Food intake using 3-day food diaries and food frequency questionnaires (FFQs). BMR and anthropometric measurements including body weight were measured on arrival in the UK and after 3 and 6 months' stay. Student's t-tests and analysis of variance (ANOVA) were used to compare the data. A significant difference (P < 0.05) was found between the energy density of the foods consumed in Malaysia and after 3 and 6 months in the UK. There was also a significant decrease (P < 0.05) in protein consumed. However, there were no differences in total energy intake. From results of the FFQs, differences were found in food selection due mainly to the lack of availability of certain foods in UK supermarkets. No significant differences were found in the BMR and anthropometric measurements made at the start of the study and later assessments. It appears that Malaysian students are able to remain in energy balance and are weight stable at least during the first 6 months of residence in the UK, despite the wider choice of energy dense food available. This suggests that at least in the short term, subjects are able to modulate their food intake in response to changes in the energy densities and free choice of food.

In view of our preliminary findings that refined palm oil (RPOL) enhanced protein utilisation, and because of the growing importance of palm oil in human diets, two separate studies were conducted. The first study aimed to investigate the effect of the palm oil source and fraction on protein utilisation, as determined by net protein utilization (NPU) in growing rats. The second study aimed to investigate the influence of the dietary concentration of one particular palm oil fraction, refined palm olein (RPO) on net protein utilisation. The fat source of each of the semi-purified diets was as follows: crude palm oil (CPO), refined palm kernel oil (RKO), refined palm olein (RPO), refined palm stearin (RPS), and refined palm oil (RPOL). A sixth control group was offered an identical diet but with olive oil (OO, control) as the fat source. Both the oil source (P < 0.01) and the oil level (P < 0.05) influenced NPU in rats. NPU values were generally higher for rats given the RPO-containing diets, particularly at the 20% dietary level (P < 0.01) compared to the diets containing ground nut oil (GNO). The results of these two experiments indicate that RPO influences protein metabolism specifically at a concentration of at least 20% in the diet. This may suggest that RPO is superior to GNO as a source of fat for the rehabilitation of malnourished children. Human trials notably during the rehabilitation of malnourished children may therefore be the next step in this line of research.