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• •The incidence of follicular lymphoma is significantly higher in European populations compared to non-European populations. • •We do not know whether these differences are caused by metabolic phenotypes linked to anthropometric indicators. • •Given the reliability of Mendelian randomization, our study aims to employ this methodology to investigate genetic associations and potential mediators between anthropometric indicators and Non-Hodgkin's lymphoma. • •Our findings indicate a causal association between higher fat-free mass and standing height in Europeans and an elevated risk of follicular lymphoma. These associations are mediated by elevated basal metabolic rates, which could potentially contribute to the higher incidence of follicular lymphoma observed in this population. Non-Hodgkin's lymphoma incidence rates vary between European and Asian populations. The reasons remain unclear. This two-sample two-step Mendelian randomisation (MR) study aimed to investigate the causal relationship between anthropometric indicators (AIs) and diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) and the possible mediating role of basal metabolic rate (BMR) in Europe. We used the following AIs as exposures: body mass index (BMI), whole-body fat mass (WBFM), whole-body fat-free mass (WBFFM), waist circumference(WC), hip circumference(HC), standing height (SH), and weight(Wt). DLBCL and FL represented the outcomes, and BMR was a mediator. A two-sample MR analysis was performed to examine the association between AIs and DLBCL and FL onset. We performed reverse-MR analysis to determine whether DLBCL and FL interfered with the AIs. A two-step MR analysis was performed to determine whether BMR mediated the causality. WBFFM and SH had causal relationships with FL. A causal association between AIs and DLBCL was not observed. Reverse-MR analysis indicated the causal relationships were not bidirectional. Two-step MR suggested BMR may mediate the causal effect of WBFFM and SH on FL. We observed a causal relationship between WBFFM and SH and the onset of FL in Europeans, Which may explain the high incidence of follicular lymphoma in Europeans. [ABSTRACT FROM AUTHOR]

Emerging evidence suggests that a metabolic profile associated with obesity may be a more relevant risk factor for some cancers than adiposity per se. Basal metabolic rate (BMR) is an indicator of overall body metabolism and may be a proxy for the impact of a specific metabolic profile on cancer risk. Therefore, we investigated the association of predicted BMR with incidence of 13 obesity‐related cancers in the European Prospective Investigation into Cancer and Nutrition (EPIC). BMR at baseline was calculated using the WHO/FAO/UNU equations and the relationships between BMR and cancer risk were investigated using multivariable Cox proportional hazards regression models. A total of 141,295 men and 317,613 women, with a mean follow‐up of 14 years were included in the analysis. Overall, higher BMR was associated with a greater risk for most cancers that have been linked with obesity. However, among normal weight participants, higher BMR was associated with elevated risks of esophageal adenocarcinoma (hazard ratio per 1‐standard deviation change in BMR [HR1‐SD]: 2.46; 95% CI 1.20; 5.03) and distal colon cancer (HR1‐SD: 1.33; 95% CI 1.001; 1.77) among men and with proximal colon (HR1‐SD: 1.16; 95% CI 1.01; 1.35), pancreatic (HR1‐SD: 1.37; 95% CI 1.13; 1.66), thyroid (HR1‐SD: 1.65; 95% CI 1.33; 2.05), postmenopausal breast (HR1‐SD: 1.17; 95% CI 1.11; 1.22) and endometrial (HR1‐SD: 1.20; 95% CI 1.03; 1.40) cancers in women. These results indicate that higher BMR may be an indicator of a metabolic phenotype associated with risk of certain cancer types, and may be a useful predictor of cancer risk independent of body fatness. What's new? Although the basal metabolic rate (BMR) – defined as the daily rate of energy metabolism required to preserve vital functions – has been positively associated with increased breast cancer risk, its relevance to other cancers remains unknown. Here, the authors examined associations between predicted BMR and risk of 13 cancers in over 520,000 individuals in Europe. Predicted BMR was generally positively associated with cancer risk. Importantly, among normal weight individuals, BMR was positively associated with cancers of the colon, pancreas, thyroid, esophageal adenocarcinoma, postmenopausal breast, and endometrium, indicating that BMR may identify subgroups of the population who are at greater risk of these malignancies. [ABSTRACT FROM AUTHOR]

A species' potential geographical range is largely determined by how the species responds physiologically to its changing environment. It is therefore crucial to study the physiological mechanisms that species use to maintain their homeothermy in order to address biodiversity conservation challenges, such as the success of invasions of introduced species. The common waxbill Estrilda astrild , the orange-cheeked waxbill E. melpoda , and the black-rumped waxbill E. troglodytes are small Afrotropical passerines that have established invasive populations in regions where the climate is colder than in their native ranges. As a result, they are highly suitable species for studying potential mechanisms for coping with a colder and more variable climate. Here, we investigated the magnitude and direction of seasonal variation in their thermoregulatory traits, such as basal (BMR), summit (M sum) metabolic rates and thermal conductance. We found that, from summer to autumn, their ability to resist colder temperatures increased. This was not related to larger body masses or higher BMR and M sum , but instead, species downregulated BMR and M sum toward the colder season, suggesting energy conservation mechanisms to increase winter survival. BMR and M sum were most strongly correlated with temperature variation in the week preceding the measurements. Common waxbill and black-rumped waxbill, whose native ranges encompass the highest degree of seasonality, showed the most flexibility in metabolic rates (i.e., stronger downregulation toward colder seasons). This ability to adjust thermoregulatory traits, combined with increased cold tolerance, may facilitate their establishment in areas characterized by colder winters and less predictable climates. • Metabolic rates of estrildid finches correlate with seasonal temperature variation. • Lower autumn cold tolerance is influenced by thermal conductance and body mass. • Metabolic rates are not correlated with cold tolerance. • Seasonal changes in thermoregulatory traits suggest an energy saving strategy. [ABSTRACT FROM AUTHOR]

Objective: To test whether youths who engage in vigorous physical activity are more likely to have lean bodies while ingesting relatively large amounts of energy. For this purpose, we studied the associations of both physical activity and adiposity with energy intake in adolescents., Study Design: The study subjects were adolescents who participated in 1 of 2 cross-sectional studies, the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study (n = 1450; mean age, 14.6 years) or the European Youth Heart Study (EYHS; n = 321; mean age, 15.6 years). Physical activity was measured by accelerometry, and energy intake was measured by 24-hour recall. In the HELENA study, body composition was assessed by 2 or more of the following methods: skinfold thickness, bioelectrical impedance analysis, plus dual-energy X-ray absorptiometry or air-displacement plethysmography in a subsample. In the EYHS, body composition was assessed by skinfold thickness., Results: Fat mass was inversely associated with energy intake in both studies and using 4 different measurement methods (P ≤ .006). Overall, fat-free mass was positively associated with energy intake in both studies, yet the results were not consistent across measurement methods in the HELENA study. Vigorous physical activity in the HELENA study (P < .05) and moderate physical activity in the EYHS (P < .01) were positively associated with energy intake. Overall, results remained unchanged after adjustment for potential confounding factors, after mutual adjustment among the main exposures (physical activity and fat mass), and after the elimination of obese subjects, who might tend to underreport energy intake, from the analyses., Conclusion: Our data are consistent with the hypothesis that more physically active and leaner adolescents have higher energy intake than less active adolescents with larger amounts of fat mass., (Copyright © 2014 Mosby, Inc. All rights reserved.)