BackgroundRecent research shows that sedentary behaviour is associated with adverse cardio-metabolic consequences even among those considered sufficiently physically active. In order to successfully develop interventions to address this unhealthy behaviour, factors that influence sedentariness need to be identified and fully understood. The aim of this review is to identify individual, social, environmental, and policy-related determinants or correlates of sedentary behaviours among adults aged 18–65 years.MethodsPubMed, Embase, CINAHL, PsycINFO and Web of Science were searched for articles published between January 2000 and September 2015. The search strategy was based on four key elements and their synonyms: (a) sedentary behaviour (b) correlates (c) types of sedentary behaviours (d) types of correlates. Articles were included if information relating to sedentary behaviour in adults (18–65 years) was reported. Studies on samples selected by disease were excluded. The full protocol is available from PROSPERO (PROSPERO 2014:CRD42014009823).Results74 original studies were identified out of 4041: 71 observational, two qualitative and one experimental study. Sedentary behaviour was primarily measured as self-reported screen leisure time and total sitting time. In 15 studies, objectively measured total sedentary time was reported: accelerometry (n = 14) and heart rate (n = 1). Individual level factors such as age, physical activity levels, body mass index, socio-economic status and mood were all significantly correlated with sedentariness. A trend towards increased amounts of leisure screen time was identified in those married or cohabiting while having children resulted in less total sitting time. Several environmental correlates were identified including proximity of green space, neighbourhood walkability and safety and weather.ConclusionsResults provide further evidence relating to several already recognised individual level factors and preliminary evidence relating to social and environmental factors that should be further investigated. Most studies relied upon cross-sectional design limiting causal inference and the heterogeneity of the sedentary measures prevented direct comparison of findings. Future research necessitates longitudinal study designs, exploration of policy-related factors, further exploration of environmental factors, analysis of inter-relationships between identified factors and better classification of sedentary behaviour domains.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-016-2841-3) contains supplementary material, which is available to authorized users.

Background: Ethnic differences in cardiometabolic risk (CMR) may be related to patterns of ethnic-specific body fat distribution. Objective: We aimed to identify differences across ethnic groups in interrelations between BMI, abdominal adiposity, liver fat, and CMR profile.

BackgroundEcological models are currently the most used approaches to classify and conceptualise determinants of sedentary behaviour, but these approaches are limited in their ability to capture the complexity of and interplay between determinants. The aim of the project described here was to develop a transdisciplinary dynamic framework, grounded in a system-based approach, for research on determinants of sedentary behaviour across the life span and intervention and policy planning and evaluation.MethodsA comprehensive concept mapping approach was used to develop the Systems Of Sedentary behaviours (SOS) framework, involving four main phases: (1) preparation, (2) generation of statements, (3) structuring (sorting and ranking), and (4) analysis and interpretation. The first two phases were undertaken between December 2013 and February 2015 by the DEDIPAC KH team (DEterminants of DIet and Physical Activity Knowledge Hub). The last two phases were completed during a two-day consensus meeting in June 2015.ResultsDuring the first phase, 550 factors regarding sedentary behaviour were listed across three age groups (i.e., youths, adults and older adults), which were reduced to a final list of 190 life course factors in phase 2 used during the consensus meeting. In total, 69 international delegates, seven invited experts and one concept mapping consultant attended the consensus meeting. The final framework obtained during that meeting consisted of six clusters of determinants: Physical Health and Wellbeing (71 % consensus), Social and Cultural Context (59 % consensus), Built and Natural Environment (65 % consensus), Psychology and Behaviour (80 % consensus), Politics and Economics (78 % consensus), and Institutional and Home Settings (78 % consensus). Conducting studies on Institutional Settings was ranked as the first research priority. The view that this framework captures a system-based map of determinants of sedentary behaviour was expressed by 89 % of the participants.ConclusionThrough an international transdisciplinary consensus process, the SOS framework was developed for the determinants of sedentary behaviour through the life course. Investigating the influence of Institutional and Home Settings was deemed to be the most important area of research to focus on at present and potentially the most modifiable. The SOS framework can be used as an important tool to prioritise future research and to develop policies to reduce sedentary time.Electronic supplementary materialThe online version of this article (doi:10.1186/s12966-016-0409-3) contains supplementary material, which is available to authorized users.

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BackgroundLow levels of physical activity (PA) are a global concern and increasing PA engagement is becoming a priority in current public health policies. Despite the large number of studies and reviews available, the evidence regarding the behavioral determinants of PA is still inconclusive. Thus, the aim of this umbrella systematic literature review (SLR) was to summarize the evidence on the behavioral determinants of PA across the life course.MethodsA systematic online search was conducted on MEDLINE, ISI Web of Science, Scopus, and SPORTDiscus databases. The search was limited to studies published in English from January, 2004 to April, 2016. SLRs and meta-analyses (MAs) of observational studies that investigated the behavioral determinants of PA were considered eligible. The extracted data were assessed based on the importance of the determinants, the strength of evidence, and the methodological quality. The full protocol is available from PROSPERO (PROSPERO 2014:CRD42015010616).ResultsSeventeen reviews on 35 behavioral determinants of PA were eligible for this umbrella SLR. Regardless of age, the most investigated determinants were those related with ‘screen use’ and ‘smoking’. For youth, probable positive evidence emerged for ‘previous PA’ and ‘independent mobility and active transport’ among children and adolescents. For the adult population, ‘transition to university’ and ‘pregnancy/having a child’ showed probable negative associations.ConclusionsAlthough the majority of the evidence was limited and most of the determinants were not associated with PA, this umbrella SLR provided a comprehensive overview of the associations between behavioral determinants and PA. Youth should be physically active in the early years and increase active transportation to/from school, independent mobility, and ‘free-range activities’ without adult supervision, whilst adult PA behaviors are mostly influenced by the life events. Finally, more research is needed that incorporates prospective study designs, standardized definitions of PA, objective measurement methods of PA assessment, and the use of interactionist and mediational approaches for the evaluation of different behavioral determinants influencing PA behaviors.

Visceral, but not sc, abdominal adiposity is strongly related to cardiometabolic risk factors and to the prevalence of cardiovascular disease and may be an important driver of cardiometabolic risk in patients regardless of type 2 diabetes status.

Type 2 diabetes is associated with a higher cardiovascular risk and there has been a growing interest in using dietary intervention to improve lipid profile and glucose control. The present work aims at analysing the effects of the enrichment of a normal diet with b-glucan (3·5 g/d) in free-living type 2 diabetic subjects for 2 months, using a palatable soup. This trial was a parallel, placebo-controlled, double-blinded randomised study performed in fifty-three type 2 diabetic subjects. During a 3-week run-in period, subjects daily consumed a ready meal control soup (without b-glucan). For the following 8 weeks, subjects were randomly assigned to consume daily either a control soup or a b-glucan soup. Changes in lipid profile (total cholesterol (TC), HDL-and LDL-cholesterol (HDLc and LDLc), apo B and TAG) and in glucose control (HbA1c and fasting glucose) were measured. There was no significant alteration in lipid profile in the two groups (TC, HDLc, LDLc and apo B). TAG decreased significantly in the b-glucan group compared with the control group (2 0·12 (SD 0·38) v. 0·12 (SD 0·44) mmol/l, P¼ 0·03). HbA1c and fasting glucose were not reduced in any group. A single daily ingestion of 3·5 g b-glucan, as required by official dietary recommendations, for 8 weeks did not change the lipid profile and HbA1c in type 2 diabetic subjects. To improve the metabolic profile of type 2 diabetic subjects in the long term, the quantity, the food vectors and the tolerability of b-glucan products may be re-evaluated.

The glycaemic index (GI) has been developed in order to classify food according to the postprandial glycaemic response. This parameter is of interest, especially for people prone to glucose intolerance; however, the effects of a low-GI (LGI) diet on body weight, carbohydrate and lipid metabolism remain controversial. We studied the effects of either a LGI or high-GI (HGI) diet on weight control and cardiovascular risk factors in overweight, non-diabetic subjects. The study was a randomized 5-week intervention trial. The thirty-eight subjects (BMI 27·3 (SEM 0·2) kg/m 2 ) followed an intervention diet in which usual starch was replaced ad libitum with either LGI or HGI starch. Mean body weight decrease was significant in the LGI group (21·1 (SEM 0·3) kg, P¼0·004) and was significantly greater than in the HGI group (20·3 (SEM 0·2) kg, P¼0·04 between groups). Hunger sensation scales showed a trend towards a decrease in hunger sensation before lunch and dinner in the LGI group when compared with the HGI group (P¼ 0·09). No significant increase in insulin sensitivity was noticed. The LGI diet also decreased total cholesterol by 9·6 % (P, 0·001), LDL-cholesterol by 8·6 % (P¼0·01) and both LDL-:HDL-cholesterol ratio (10·1 %, P¼ 0·003) and total:HDL-cholesterol ratio (8·5 %, P¼0·001) while no significant changes were observed in the HGI group. Lowering the GI of daily meals with simple dietary recommendations results in increased weight loss and improved lipid profile and is relatively easy to implement with few constraints. These potential benefits of consuming a LGI diet can be useful to develop practical dietetic advice. The notion of glycaemic index (GI) was introduced two decades ago to compare food exchanges within carbohydrate food categories 1 . Two tables of GI values were successively published in 1995 2 and 2002 3 and referenced nearly 1300 foods and ingredients. The classification of carbohydrates into simple or complex carbohydrates is of little use for food GI prediction. GI is influenced by starch structure itself, manufacture and cooking processes, which play a considerable role in the final GI 4,5 . In fact, dietary carbohydrates influence metabolism by at least four mechanisms: nature of the monosaccharides absorbed; amount of carbohydrate consumed; rate of absorption; colonic fermentation 6 . Then, GI was proposed as a way to reduce postprandial glucose and insulin peaks -a situation that could have health benefits, in particular towards obesity, diabetes development and cardiovascular risk 7 -12 . Despite controversial literature data, dietary GI is potentially important in the treatment and prevention of chronic diseases and cancers 7 .Many studies over the past two decades performed with diabetic subjects have shown that low-GI (LGI) regimens were able to improve glucose tolerance and plasma insulin sensitivity.LGI diets would also be beneficial through a more moderate insulin response (lower postprandial peak). Acute experiments in healthy subjects have shown a decrease in 24 h glucose concentrati...