Sedentary time has a stronger impact on metabolic health than moderate to vigorous physical activity in adolescents with obesity: a cross-sectional analysis of the Beta-JUDO study.

BACKGROUND: Relationships between movement-related behaviours and metabolic health remain underexplored in adolescents with obesity. OBJECTIVES: To compare profiles of sedentary time (more sedentary, SED+ vs. less sedentary, SED-), moderate to vigorous physical activity (MVPA) time (more active, MVPA+ vs. less active, MVPA-) and combinations of behaviours (SED-/MVPA+, SED-/MVPA-, SED+/MVPA+, SED+/MVPA-) in regard to metabolic health. METHODS: One hundred and thirty-four subjects (mean age 13.4 ± 2.2 yrs, mean body mass index [BMI] 98.9 ± 0.7 percentile, 48.5% females) underwent 24 h/7 day accelerometry, anthropometric, body composition, blood pressure (BP), lipid profile and insulin resistance (IR) assessments. RESULTS: Metabolic health was better in SED- [lower fat mass (FM) percentage (p < 0.05), blood pressure (BP) (p < 0.05), homeostasis model assessment of insulin resistance (HOMA-IR) (p < 0.001) and metabolic syndrome risk score (MetScore) (p < 0.001), higher high-density lipoprotein-cholesterol (HDL-c) (p = 0.001)] vs. SED+ group and in MVPA+ [lower triglyceridemia (TG), (p < 0.05), HOMA-IR (p < 0.01) and MetScore (p < 0.001), higher HDL-c (p < 0.01)] vs. MVPA- group after adjustment with age, gender, maturation and BMI. SED-/MVPA+ group had the best metabolic health. While sedentary (p < 0.001) but also MVPA times (p < 0.001) were lower in SED-/MVPA- vs. SED+/MVPA+, SED-/MVPA- had lower FM percentage (p < 0.05), HOMA-IR (p < 0.01) and MetScore (p < 0.05) and higher HDL-c (p < 0.05), independently of BMI. Sedentary time was positively correlated with HOMA-IR and Metscore and negatively correlated with HDL-c after adjustment with MVPA (p < 0.05). MVPA was negatively correlated with HOMA-IR, BP and MetScore and positively correlated with HDL-c after adjustment with sedentary time (p < 0.05). CONCLUSION: Lower sedentary time is associated with a better metabolic health independently of MVPA and might be a first step in the management of pediatric obesity when increasing MVPA is not possible.

Overeating Saturated Fat Promotes Fatty Liver and Ceramides Compared With Polyunsaturated Fat: A Randomized Trial.

CONTEXT: Saturated fatty acid (SFA) vs polyunsaturated fatty acid (PUFA) may promote nonalcoholic fatty liver disease by yet unclear mechanisms. OBJECTIVE: To investigate if overeating SFA- and PUFA-enriched diets lead to differential liver fat accumulation in overweight and obese humans. DESIGN: Double-blind randomized trial (LIPOGAIN-2). Overfeeding SFA vs PUFA for 8 weeks, followed by 4 weeks of caloric restriction. SETTING: General community. PARTICIPANTS: Men and women who are overweight or have obesity (n = 61). INTERVENTION: Muffins, high in either palm (SFA) or sunflower oil (PUFA), were added to the habitual diet. MAIN OUTCOME MEASURES: Lean tissue mass (not reported here). Secondary and exploratory outcomes included liver and ectopic fat depots. RESULTS: By design, body weight gain was similar in SFA (2.31 ± 1.38 kg) and PUFA (2.01 ± 1.90 kg) groups, P = 0.50. SFA markedly induced liver fat content (50% relative increase) along with liver enzymes and atherogenic serum lipids. In contrast, despite similar weight gain, PUFA did not increase liver fat or liver enzymes or cause any adverse effects on blood lipids. SFA had no differential effect on the accumulation of visceral fat, pancreas fat, or total body fat compared with PUFA. SFA consistently increased, whereas PUFA reduced circulating ceramides, changes that were moderately associated with liver fat changes and proposed markers of hepatic lipogenesis. The adverse metabolic effects of SFA were reversed by calorie restriction. CONCLUSIONS: SFA markedly induces liver fat and serum ceramides, whereas dietary PUFA prevents liver fat accumulation and reduces ceramides and hyperlipidemia during excess energy intake and weight gain in overweight individuals.

A concept for holistic whole body MRI data analysis, Imiomics.

PURPOSE: To present and evaluate a whole-body image analysis concept, Imiomics (imaging-omics) and an image registration method that enables Imiomics analyses by deforming all image data to a common coordinate system, so that the information in each voxel can be compared between persons or within a person over time and integrated with non-imaging data. METHODS: The presented image registration method utilizes relative elasticity constraints of different tissue obtained from whole-body water-fat MRI. The registration method is evaluated by inverse consistency and Dice coefficients and the Imiomics concept is evaluated by example analyses of importance for metabolic research using non-imaging parameters where we know what to expect. The example analyses include whole body imaging atlas creation, anomaly detection, and cross-sectional and longitudinal analysis. RESULTS: The image registration method evaluation on 128 subjects shows low inverse consistency errors and high Dice coefficients. Also, the statistical atlas with fat content intensity values shows low standard deviation values, indicating successful deformations to the common coordinate system. The example analyses show expected associations and correlations which agree with explicit measurements, and thereby illustrate the usefulness of the proposed Imiomics concept. CONCLUSIONS: The registration method is well-suited for Imiomics analyses, which enable analyses of relationships to non-imaging data, e.g. clinical data, in new types of holistic targeted and untargeted big-data analysis.

Dietary intake of eicosapentaenoic and docosahexaenoic acids is linked to gray matter volume and cognitive function in elderly.

In the present study, we tested whether elderly with a high dietary intake of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) would have higher cognitive test scores and greater brain volume than those with low dietary intake of these fatty acids. Data were obtained from the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) cohort. The dietary intake of EPA and DHA was determined by a 7-day food protocol in 252 cognitively healthy elderly (122 females) at the age of 70 years. At age 75, participants' global cognitive function was examined, and their brain volumes were measured by magnetic resonance imaging (MRI). Three different multivariate linear regression models were applied to test our hypothesis: model A (adjusted for gender and age), model B (additionally controlled for lifestyle factors, e.g., education), and model C (further controlled for cardiometabolic factors, e.g., systolic blood pressure). We found that the self-reported 7-day dietary intake of EPA and DHA at the age of 70 years was positively associated with global gray matter volume (P < 0.05, except for model C) and increased global cognitive performance score (P < 0.05). However, no significant associations were observed between the dietary intake of EPA and DHA and global white matter, total brain volume, and regional gray matter, respectively. Further, no effects were observed when examining cognitively impaired (n = 27) elderly as separate analyses. These cross-sectional findings suggest that dietary intake of EPA and DHA may be linked to improved cognitive health in late life but must be confirmed in patient studies.