Risk evaluation of vitamin D insufficiency or deficiency in children using simple scores: The Healthy Growth Study.

Although identification of population groups at high risk for low vitamin D status is of public health importance,there are no risk prediction tools available for children in Southern Europe that can cover this need. The present study aimed to develop and validate 2 simple scores that evaluate the risk for vitamin D insufficiency or deficiency in children. A cross-sectional epidemiological study was conducted among 2280 schoolchildren (9--13-year-old) living in Greece. The total sample was randomly divided into 2 subsamples of 1524 and 756 children, used in the development and validation of the 2 scores, respectively. Multivariate logistic regression analyses were used to develop the 2 risk evaluation scores, while receiver operating characteristic curves were employed to identify the optimal "points of change" for each risk score, upon which vitamin D insufficiency and deficiency is diagnosed with the highest possible sensitivity and specificity. The components of the 2 risk evaluation scores included children's age, gender, region of residence, screen-time, body weight status, maternal education, and season. The increase in each score by 1 unit elevated the likelihood for vitamin D insufficiency and deficiency by 31% and 28%, respectively. The receiver operating characteristic curves showed that the optimal "points of change" for each risk score, upon which vitamin D insufficiency or deficiency is diagnosed with the highest possible sensitivity and specificity were 8.5 and 12.5, respectively. In conclusion, this study developed 2 simple scores that evaluate the risk for vitamin D insufficiency or deficiency in children living in Greece. However, more studies are required for these scores to be validated in other populations of children from different countries.

Vitamin D Serum Levels in the UK Population, including a Mathematical Approach to Evaluate the Impact of Vitamin D Fortified Ready-to-Eat Breakfast Cereals: Application of the NDNS Database.

Vitamin D status is relatively poor in the general population, potentially leading to various conditions. The present study evaluates the relationship between vitamin D status and intake in the UK population and the impact of vitamin D fortified ready-to-eat cereals (RTEC) on this status via data from the National Diet and Nutrition Survey (NDNS: 2008-2012). Four cohorts were addressed: ages 4-10 (n = 803), ages 11-18 (n = 884), ages 19-64 (n = 1655) and ages 65 and higher (n = 428). The impact of fortification by 4.2 µg vitamin D per 100 g of RTEC on vitamin D intake and status was mathematically modelled. Average vitamin D daily intake was age-dependent, ranging from ~2.6 (age range 4-18 years) to ~5.0 µg (older than 64 years). Average 25(OH)D concentration ranged from 43 to 51 nmol/L, the highest in children. The relationship between vitamin D intake and status followed an asymptotic curve with a predicted plateau concentration ranging from 52 in children to 83 nmol/L in elderly. The fortification model showed that serum concentrations increased with ~1.0 in children to ~6.5 nmol/L in the elderly. This study revealed that vitamin D intake in the UK population is low with 25(OH)D concentrations being suboptimal for general health. Fortification of breakfast cereals can contribute to improve overall vitamin D status.

Vitamin D insufficiency is associated with insulin resistance independently of obesity in primary schoolchildren. The healthy growth study.

OBJECTIVES: To explore the associations of vitamin D status and obesity with insulin resistance (IR) in children. METHODS: A sample of 2282 schoolchildren (9-13 years old) in Greece was examined. Sociodemographic, anthropometric (weight, height), biochemical (fasting plasma glucose, serum insulin and 25(OH)D), pubertal status and physical activity data were collected, using standard methods. The "Vitamin D Standardization Program" protocol was applied to standardize serum 25(OH)D values. RESULTS: The prevalence of vitamin D insufficiency (serum 25(OH)D < 50 nmol/L) was higher in obese children compared to their over- and normal-weight counterparts (60.5% vs 51.6% and 51%, P = .017). Furthermore, children with IR (both obese and non-obese) had higher prevalence of vitamin D insufficiency compared to non-obese, non-insulin resistant children (66% and 59.2% vs 49.8%, P < .05), possibly indicating that IR is associated with vitamin D insufficiency, independently of obesity. In line with the above, the results from logistic regression analyses controlled for several potential confounders, showed a 1.48 (95% C.I: 1.2-1.84) higher likelihood for vitamin D insufficiency for insulin resistant children compared to the non-insulin resistant ones, while no significant association was observed with obesity. CONCLUSIONS: The present study revealed a high prevalence of vitamin D insufficiency among schoolchildren in Greece, particularly among obese and insulin resistant ones. In addition, it highlighted that the significant association of vitamin D insufficiency with IR is possibly independent of obesity. Further clinical trials are needed to confirm this possible independent association but also explore the potential beneficial effect of vitamin D supplementation on IR and possibly on weight management too.

Prevalence of vitamin D deficiency and insufficiency among schoolchildren in Greece: the role of sex, degree of urbanisation and seasonality.

The current study was aiming to report the prevalence of suboptimal vitamin D status among schoolchildren in Greece and investigate the role of sex, urbanisation and seasonality on vitamin D status. A sample of 2386 schoolchildren (9-13 years old) from four distinct prefectures was examined. The prevalence of 25-hydroxyvitamin D (25(OH)D) concentration <30 and <50 nmol/l (vitamin D deficiency and insufficiency respectively) was 5·2 and 52·5 %, respectively. Girls had a higher prevalence of 25(OH)D<30 (7·2 v. 3·2 %) and 50 nmol/l (57·0 v. 48·0 %) than boys (P<0·001). The highest prevalence rates of 25(OH)D<30 and 50 nmol/l (9·1 and 73·1 %, respectively) were observed during spring (April to June), whereas the lowest (1·5 and 31·9 %, respectively) during autumn (October to December). The prevalence of 25(OH)D<50 nmol/l was higher in urban/semi-urban than rural regions, particularly during spring months (74·6 v. 47·2 %; P<0·001). Female sex, urban/semi-urban region of residence and spring months were found to increase the likelihood of vitamin D deficiency and insufficiency, with the highest OR observed for spring months (7·47; 95 % CI 3·23, 17·3 and 5·14; 95 % CI 3·84, 6·89 for 25(OH)D<30 and 50 nmol/l respectively). In conclusion, despite the southerly latitude, the prevalence of low vitamin D status among primary schoolchildren in Greece is comparable to or exceeds the prevalence reported among children and adolescents on a European level. Sub-populations at highest risk are girls in urban/semi-urban areas during spring months, thus indicating the need for effective initiatives to support adequate vitamin D status in these population groups.

Availability and dose response of phytophenols from a wheat bran rich cereal product in healthy human volunteers.

SCOPE: Phytophenols present in cereals are metabolised to compounds that could be partly responsible for the reduced risk of chronic diseases and all-cause mortality associated with fibre-rich diets. The bioavailability, form and in vivo concentrations of these metabolites require to be established. MATERIALS AND METHODS: Eight healthy volunteers consumed a test meal containing a recommended dose (40 g) and high dose (120 g) of ready-to-eat wheat bran cereal and the systemic and colonic metabolites determined quantitatively by LC-MS. CONCLUSION: Analysis of the systemic metabolomes demonstrated that a wide range of phytophenols were absorbed/excreted (43 metabolites) within 5 h of consumption. These included 16 of the 21 major parent compounds identified in the intervention product and several of these were also found to be significantly increased in the colon. Not all of the metabolites were increased with the higher dose, suggesting some limitation in absorption due to intrinsic factors and/or the food matrix. Many compounds identified (e.g. ferulic acid and major metabolites) exhibit anti-inflammatory activity and impact on redox pathways. The combination of postprandial absorption and delivery to the colon, as well as hepatic recycling of the metabolites at these concentrations, is likely to be beneficial to both systemic and gut health.

Effects of Cereal, Fruit and Vegetable Fibers on Human Fecal Weight and Transit Time: A Comprehensive Review of Intervention Trials.

Cereal fibers are known to increase fecal weight and speed transit time, but far less data are available on the effects of fruits and vegetable fibers on regularity. This study provides a comprehensive review of the impact of these three fiber sources on regularity in healthy humans. We identified English-language intervention studies on dietary fibers and regularity and performed weighted linear regression analyses for fecal weight and transit time. Cereal and vegetable fiber groups had comparable effects on fecal weight; both contributed to it more than fruit fibers. Less fermentable fibers increased fecal weight to a greater degree than more fermentable fibers. Dietary fiber did not change transit time in those with an initial time of <48 h. In those with an initial transit time ≥48 h, transit time was reduced by approximately 30 min per gram of cereal, fruit or vegetable fibers, regardless of fermentability. Cereal fibers have been studied more than any other kind in relation to regularity. This is the first comprehensive review comparing the effects of the three major food sources of fiber on bowel function and regularity since 1993.

Consumer understanding, interpretation and perceived levels of personal responsibility in relation to satiety-related claims.

The aim of this study was to explore (a) whether and how consumers may (over-) interpret satiety claims, and (b) whether and to what extent consumers recognize that personal efforts are required to realize possible satiety-related or weight loss benefits. Following means-end chain theory, we explored for a number of satiety claims the extent of inference-making to higher-level benefits than actually stated in the claim, using internet-based questions and tasks. Respondents (N=1504) in U.K., France, Italy and Germany participated in the study. The majority of these respondents correctly interpret satiety-related claims; i.e. they largely limit their interpretation to what was actually stated. They do not expect a "magic bullet" effect, but understand that personal efforts are required to translate product attributes into potential weight control benefits. Less-restrained eaters were at lower risk for over-interpreting satiety-related claims, whilst respondents with a stronger belief that their weight is something that they can control accept more personal responsibility, and better understand that personal efforts are required to be effective in weight control. Overall, these results indicate there is likely to be a relatively low level of consumer misinterpretation of satiety-related claims on food products.

Glycemic response and health--a systematic review and meta-analysis: the database, study characteristics, and macronutrient intakes.

BACKGROUND: Reduction of dietary glycemic response has been proposed as a means of reducing the risk of diabetes and coronary heart disease. Its role in health maintenance and management, alongside unavailable carbohydrate (eg, fiber), is incompletely understood. OBJECTIVE: We aimed to assess the evidence relating the glycemic impact of foods to a role in health maintenance and management of disease. DESIGN: We searched the literature for relevant controlled dietary intervention trials on glycemic index (GI) according to inclusion and exclusion criteria, extracted the data to a database, and synthesized the evidence via meta-analyses and meta-regression models. RESULTS: Among literature to January 2005, 45 relevant publications were identified involving 972 subjects with good health or metabolic disease. With small reductions in GI (<10 units), increases in available carbohydrate, energy, and protein intakes were found in all studies combined. Falling trends in energy, available carbohydrate, and protein intakes then occurred with progressive reductions in GI. Fat intake was essentially unchanged. Unavailable carbohydrate intake was generally higher for intervention diets but showed no trend with GI (falling or rising). Among studies reporting on GI, variation in glycemic load was approximately equally explained by variation in GI and variation in available carbohydrate intake. An exchange of available and unavailable carbohydrate (approximately 1 g/g) was evident in these studies. CONCLUSIONS: Among GI studies, observed reductions in glycemic load are most often not solely due to substitution of high for low glycemic carbohydrate foods. Available carbohydrate intake is a confounding factor. The role of unavailable carbohydrate remains to be accounted for.

Glycemic response and health--a systematic review and meta-analysis: relations between dietary glycemic properties and health outcomes.

BACKGROUND: Reduction of dietary glycemic response has been proposed as a means of reducing the risk of diabetes and coronary heart disease. The impact of glycemic response on markers of health remains to be elucidated. OBJECTIVE: We assessed the evidence relating the glycemic impact of foods to measures relevant for health maintenance and management of disease. DESIGN: This was a systematic review and synthesis of interventional evidence from literature reported on glycemic index and markers of health through the use of meta-analyses and meta-regression models. RESULTS: Data from 45 relevant publications were found to January 2005. Lower glycemic index (GI) diets reduced both fasting blood glucose and glycated proteins independently of variance in available and unavailable carbohydrate intakes. Elevated unavailable carbohydrate added to improvements in both blood glucose and glycated protein control. These effects were greater in persons with poor fasting blood glucose control. No effects were seen on fasting insulin<100 pmol/L; above this, study numbers were few but consistent with prevention of hyperinsulinemia in some but not all overweight persons. Insulin sensitivity according to a variety of measurement methods was improved by lower GI, higher unavailable carbohydrate interventions in persons with type 2 diabetes, in overweight and obese persons, and in all studies combined. Fasting triacylglycerol in addition to body weight reduction related more to glycemic load than to GI. Glycemic load reduction by >17 g glucose equivalents/d was associated with reduced body weight. CONCLUSIONS: Consumption of reduced glycemic response diets are followed by favorable changes in the health markers examined. The case for the use of such diets looks compelling. Unavailable carbohydrate intake is equally important.