The bioelectrical impedance analysis (BIA) international database: aims, scope, and call for data.

BACKGROUND: Bioelectrical impedance analysis (BIA) is a technique widely used for estimating body composition and health-related parameters. The technology is relatively simple, quick, and non-invasive, and is currently used globally in diverse settings, including private clinicians' offices, sports and health clubs, and hospitals, and across a spectrum of age, body weight, and disease states. BIA parameters can be used to estimate body composition (fat, fat-free mass, total-body water and its compartments). Moreover, raw measurements including resistance, reactance, phase angle, and impedance vector length can also be used to track health-related markers, including hydration and malnutrition, and disease-prognostic, athletic and general health status. Body composition shows profound variability in association with age, sex, race and ethnicity, geographic ancestry, lifestyle, and health status. To advance understanding of this variability, we propose to develop a large and diverse multi-country dataset of BIA raw measures and derived body components. The aim of this paper is to describe the 'BIA International Database' project and encourage researchers to join the consortium. METHODS: The Exercise and Health Laboratory of the Faculty of Human Kinetics, University of Lisbon has agreed to host the database using an online portal. At present, the database contains 277,922 measures from individuals ranging from 11 months to 102 years, along with additional data on these participants. CONCLUSION: The BIA International Database represents a key resource for research on body composition.

Diet and sedentary behaviour in relation to mortality in US adults with a cardiovascular condition: results from the National Health and Nutrition Examination Survey linked to the US mortality registry.

CVD is the most common chronic condition and the highest cause of mortality in the USA. The aim of the present work was to investigate diet and sedentary behaviour in relation to mortality in US CVD survivors. The National Health and Nutrition Examination Surveys conducted between 1999 and 2014 linked to the US mortality registry updated to 2015 were investigated. Multivariate adjusted Cox regression was used to derive mortality hazards in relation to sedentary behaviour and nutrient intake. A multiplicative and additive interaction analysis was conducted to evaluate how sedentariness and diet influence mortality in US CVD survivors. A sample of 2473 participants followed for a median period of 5·6 years resulted in 761 deaths, and 199 deaths were due to CVD. A monotone increasing relationship between time spent in sedentary activities and mortality risk was observed for all-cause and CVD mortality (hazard ratio (HR) = 1·20, 95 % CI 1·09, 1·31 and HR = 1·19, 95 % CI 1·00, 1·67, respectively). Inverse mortality risks in the range of 22-34 % were observed when comparing the highest with the lowest tertile of dietary fibre, vitamin A, carotene, riboflavin and vitamin C. Sedentariness below 360 min/d and dietary fibre and vitamin intake above the median interact on an additive scale influencing positively all-cause and CVD mortality risk. Reduced sedentariness in combination with a varied diet rich in dietary fibre and vitamins appears to be a useful strategy to reduce all-cause and CVD mortality in US CVD survivors.

Substitution of sedentary time with light physical activity is related to increased bone density in U.S. women over 50 years old. An iso-temporal substitution analysis based on the National health and Nutrition Examination Survey.

U.S. women are ageing. This is causing rises in osteoporosis prevalence and risk of fracture with related increases in health care costs. Replacing sedentary time with light physical activity may represent a cost effective public health solution to osteoporosis in elderly women. The National Health and Nutrition Examination Survey conducted over the period 2003-2006 provided cross-sectional data on bone mineral density and objectively assessed physical activity among 1,052 women aged 50-85 years old. Substitution analysis was applied to estimate increased bone mineral density and reduced osteoporosis for those women replacing 30 min of sedentary time with an equivalent amount of light physical activity. Substitution of 30 min of sedentary time with an equal amount of light physical activity was associated with increased bone mineral density of about 3 mg/cm2 and a 12% reduced risk of osteoporosis in the spine. When considering overweight women and women over 65 years of age, this association was reinforced and it extended to the pelvis, legs and trunk, resulting in a consistent bone mineral density increase of about 3-6 mg/cm2. The substitution of 30 min of sedentary time with an equal amount of light physical activity appears a possible primary prevention method to reduce osteoporosis and related increases in risk of fracture, mortality, and health care costs in women over 50 years old.

School environment, socioeconomic status and weight of children in Bloemfontein, South Africa.

BACKGROUND: The continued existence of undernutrition, associated with a steady increase in the prevalence of overweight and obesity in children and adolescents, necessitates identification of factors contributing to this double burden of disease, in order for effective treatment and prevention programmes to be planned. AIM: To determine the nutritional status of 13-15-year-old children in Bloemfontein and its association with socioeconomic factors. SETTING: Bloemfontein, Free State Province, South Africa (2006). METHODS: This was a cross-sectional analytical study. Randomly selected children (n = 415) completed structured questionnaires on socioeconomic status. The children's weight and height were measured and body mass index-for-age and height-for-age z-scores were computed according to World Health Organization growth standards in order to determine the prevalence of underweight, overweight, obesity and stunting. Waist circumference was measured to classify the children as having a high or very high risk for metabolic disease. RESULTS: Of the 415 children who consented to participate in the study, 14.9% were wasted and 3.4% were severely wasted. Only 6% of the children were overweight/obese. Significantly more boys (23.0%) were wasted than girls (10%) and severe stunting was also significantly higher in boys than in girls (10.3% and 4.2%, respectively). Children whose parents had graduate occupations were significantly more overweight/obese than those with parents working in skilled occupations. Stunting was significantly higher in low (31.4%) and medium (30.4%) socioeconomic groups compared to the high socioeconomic group (18.1%). CONCLUSION: A coexistence of underweight and overweight was found and gender and parental occupation were identified as being predictors of nutritional status.

The relationship between iron status and adiposity in women from developing countries: a review.

Scientific reports have shown that iron deficiency is positively associated with adiposity. With the high prevalence of iron deficiency and obesity in developing countries and women being particularly affected, this review was carried out with the aim of elucidating the link between iron status and adiposity in women from developing countries and to examine factors influencing this relationship. An extensive literature search was conducted using several search engines. A systematic approach with prespecified inclusion criteria was used in selecting relevant literature. Eight studies that met the inclusion criteria were selected for review. The relationship between iron status indices and adiposity in women in developing countries varied widely. While some studies observed negative relationships, some reported positive relationships, and others no significant relationships. Furthermore, other factors such as infection, alcohol consumption, type of diet, and genes were shown to affect the relationship between iron status and adiposity in women in developing countries. In conclusion, the possibility of iron status playing a role in adiposity in women from developing countries is likely, and it may be influenced by several other factors as described in the results. Thus, it is recommended that a special research effort should be directed toward this area.

Overfatness, stunting and physical inactivity are determinants of plasminogen activator inhibitor-1activity, fibrinogen and thrombin-antithrombin complex in African adolescents.

We examined fibrinogen, thrombin-antithrombin complex, factor VIIIc and plasminogen activator inhibitor-1 activity in African children in order to determine haemostatic profile patterning and to identify possible subdivisions at high risk for cardiovascular disease. In a cross-sectional analysis, a convenience sample of 117 girls and 78 boys (15.6 +/- 1.35 years) in a South African township was investigated within the Physical Activity in Youth study. Haemostatic variables were investigated in the total group and subdivisions for physical activity levels, maturity (Tanner staging), sex, fat percentage and height for age. Overfatness (53.6%) coexisted with stunting (17.5%). Plasminogen activator inhibitor-1 activity differed significantly between the sexes after adjustments for fat percentage and physical activity levels. Sex explained 10% and muscle mass 1% of the variance in plasminogen activator inhibitor-1 activity. Fibrinogen was significantly higher in girls than in boys (before adjustment for fat percentage), in overfat than in lean children and in stunted than in the nonstunted children (even after adjustment for fat percentage). C-reactive protein, sex and height for age were predictors of fibrinogen. Thrombin-antithrombin complex was significantly higher in girls than in boys, but after separate adjustment for physical activity and fat percentage there were no significant differences. Fitness and muscle mass explained the variance in thrombin-antithrombin complex the best. No significant differences were seen between the groups for C-reactive protein and factor VIIIc. Overfatness, stunting and inactivity negatively influenced plasminogen activator inhibitor-1 activity, fibrinogen and thrombin-antithrombin complex possibly increased the risk for cardiovascular disease. These factors are modifiable through behavioural changes and optimal nutritional status throughout the early life.