Recent epidemiological studies show the associations of serum antioxidant status with the metabolic syndrome. Oxidative stress may play an important role in the pathogenesis of diabetes and CVD. Actually, smoking is a potent oxidative stressor in man, but little is known about the interaction of serum carotenoids and the metabolic syndrome with smoking status. In this study, the associations of the serum carotenoids with the metabolic syndrome stratified by smoking habit were evaluated cross-sectionally. A total of 1073 subjects (357 male and 716 female) who had received health examinations in the town of Mikkabi, Shizuoka Prefecture, Japan, participated in the study. Among total subjects, the OR for the metabolic syndrome in the highest tertile of serum β-carotene was 0·41 (95 % CI 0·18, 0·92) after adjusting confounders. In current smokers, significantly lower OR were observed in the middle (OR 0·10; 95 % CI 0·01, 0·72) and highest (OR 0·06; 95 % CI 0·01, 0·73) tertiles of serum β-carotene. Furthermore, lower OR were observed in accordance with tertiles of serum α-carotene and β-cryptoxanthin in current smokers (P for trend 0·042 and 0·036, respectively). In contrast, in non-smokers, a significantly lower OR was observed in the highest tertile of serum β-carotene (OR 0·30; 95 % CI 0·10, 0·89) after multiple adjustment. Inverse associations of serum carotenoids with the metabolic syndrome were more evident among current smokers than non-smokers. These results support that antioxidant carotenoids may have a protective effect against development of the metabolic syndrome, especially in current smokers who are exposed to a potent oxidative stress.

We measured the blood uptake of meso-zeaxanthin (MZ) from a mixture of macular pigments since its bioavailability in man has not been studied. Volunteers (ten men and nine women) were recruited and received one capsule of Lutein Plus®/d. Blood was taken at baseline, day 10 and day 22. One capsule contained 10·8 mg lutein, 1·2 mg (3R,3′R)-zeaxanthin and 8·0 mg MZ. Plasma lutein and total zeaxanthin concentrations were quantified using isocratic liquid chromatography and the eluting xanthophyll fractions were collected and re-chromatographed on a chiral column to assess the proportion of MZ. Plasma concentrations per mg dose at day 22 suggested that (3R,3′R)-zeaxanthin (0·088 μmol/l per mg) was about 50 % more actively retained by the body than lutein (0·056 μmol/l per mg) (although the difference was not significant in women) and 2·5–3·0 times more than MZ (0·026 μmol/l per mg). Concentrations of MZ at day 22 were 2·5 times higher in women than men. The plasma responses from lutein and (3R,3′R)-zeaxanthin in the Lutein Plus® were lower than literature values for the pure substances. That is, their uptake into plasma appeared to be slightly depressed by the presence of MZ. Plasma concentrations of β-carotene were depressed by about 50 % at day 10 and about 35 % at day 22. In conclusion, the lower plasma response to MZ compared with (3R,3′R)-zeaxanthin probably indicates that MZ is less well absorbed than (3R,3′R)-zeaxanthin but work with pure MZ will be needed to confirm that the lower plasma response was not due to the large amount of lutein in the Lutein Plus®.

Metabolic body size of veal calves is still calculated by using the 0·75 exponent and no data were available to determine energy cost of physical activity during the whole fattening period. Data from two trials focusing on protein and/or energy requirements were used to determine the coefficient of metabolic body size and the energy cost of standing activity in male Prim'Holstein calves. Total heat production was measured by indirect calorimetry in ninety-five calves weighing 60–265 kg and was divided using a modelling approach between components related to the BMR, physical activity and feed intake. The calculation of the energy cost of standing activity was based on quantifying the physical activity by using force sensors on which the metabolism cage was placed and on the interruption of an IR beam allowing the determination of standing or lying position of the calf. The best exponent relating zero activity fasting heat production (FHP0) to metabolic body size was 0·85, which differed significantly from the traditionally used 0·75. Per additional kJ metabolizable energy (ME) intake, FHP0 increased by 0·28 kJ; at a conventional daily 650 kJ/kg body weight (BW)0·85 ME intake, daily FHP0 averaged 310 kJ/kg BW0·85. Calves stood up sixteen times per day; total duration of standing increased from 5·1 to 6·4 h per day as animals became older. The hourly energy cost of standing activity was proportional to BW0·65 and was estimated as 12·4 kJ/kg BW0·65. These estimates allow for a better estimation of the maintenance energy requirements in veal calves.

Exposure to the sight and smell of food influences our momentary desire to consume it. This study explored the process by which cue exposure promotes greater consumption of food. Three hypotheses were explored, cue exposure: (i) increases the planned consumption of food; (ii) increases tolerance of larger portion sizes; (iii) arrests the development of satiety. Female participants (n 50) were each tested in two conditions. In a ‘cue condition’ they were exposed to the sight and smell of pizza for 60 s. Before and after this period they provided information about prospective and maximum tolerated portion sizes and their desire to eat pizza and other non-cued foods. Participants then consumed a fixed portion of pizza, rated their hunger and were finally offered ad libitum access to pizza. In the ‘no-cue condition’, cue exposure was replaced with a cognitive task. Cueing had little effect on tolerance of larger portion sizes or on hunger after consuming the fixed portion. Instead, it increased prospective pizza portion size and subsequent intake of pizza. Together, these results suggest that cueing increases the amount of food that people actively plan to eat. This plan is then executed, leading to greater intake. Pizza cueing also increased prospective portion size of other foods. Thus, contrary to previous reports, effects of exposure may generalise to other foods. Finally, we found evidence that restrained eaters are less ‘cue reactive’ than unrestrained eaters. In future, our approach might be adapted to consider whether heightened ‘cue reactivity’ represents a risk factor for obesity.

The aim of the present study was to investigate the interaction between the angiotensin-converting enzyme 1 (ACE) I/D polymorphism and energy and macronutrient intakes on adiposity-related phenotypes among toddlers and preschoolers. A representative sample of 2374 Greek children aged 1 to 5 years old was examined (Growth, Exercise and Nutrition Epidemiological Study in preSchoolers (GENESIS)). Dietary and anthropometric (i.e. BMI, waist circumference (WC)) assessments were carried out using standard procedures. DNA samples were obtained from 2102 children and were genotyped for the ACE I/D polymorphism. Among the entire population, 17 % were ‘at risk of overweight’ and a similar percentage were ‘overweight’. The frequencies of the II, ID and DD genotypes were 16, 46 and 38 %, respectively. Significant interactions were found between the ACE I/D polymorphism and total energy intake on WC (P = 0·004 for interaction) and the ACE I/D polymorphism and protein intake on BMI and being overweight (P < 0·05 for interaction). Furthermore, it was found that the ACE I/D polymorphism may modify the effect of fat intake on WC and BMI, but this interaction disappeared after adjustment for additional potential confounders. Stratified analyses revealed that total energy is correlated with WC and protein intake is associated with BMI and being overweight only among carriers of the D-allele (i.e. DD or ID genotypes). These results suggest that the ACE I/D polymorphism may act as a modifying factor in the response of adiposity-related phenotypes to diet.

We read the paper by Danzeisen et al.(1) with interest and would like to take issue with the authors on a number of topics.

The response by Brewer & Althaus to our recent review on biomarkers for Cu(1) bears testimony that the subject is topical and of public, scientific and commercial interest.

A recent paper published in the British Journal of Nutrition suggested possible reductions in mortality in association with the use of dietary supplements

Dr Boucher raises the question of the use of vitamin D supplements in the prospective population-based study of mortality performed among

We recently reported a null outcome from a study of n-3 long-chain PUFA supplementation in depressed mood(1).