Dietary habits among 177,091 Greek schoolchildren by age, sex, weight status, region, and living area. A cross-sectional study

BACKGROUND

This study aimed to investigate the dietary habits from early childhood to adolescence among participants from all regions of the country and living areas (rural/urban) and assess potential associations between dietary habits and obesity in both sexes.

METHODS

Population data were derived from a cross-sectional health survey on a representative sample of 177,091 children aged 6-18 years. Dietary habits were considered via a self-completed questionnaire (Mediterranean diet quality index for children and adolescents [KIDMED]). Trained investigators assessed the anthropometric data.

RESULTS

KIDMED scores were 6.7 ± 2.4 and 6.8 ± 2.3 for boys and girls, respectively, whereas a percentage of almost 10% of the total study population had insufficient dietary habits. Dietary habits peaked around age 11 years and then gradually worsened until the end of adolescence in both sexes, with an annual trend equal to -0.28 ± 0.02 (p < 0.001) for boys and -0.31 ± 0.03 (p < 0.001) for girls. Schoolchildren who are overweight/obese presented higher percentages in all unhealthy dietary habits (e.g., skipping breakfast, going often to a fast food restaurant, and consuming a lot of sweets) than children with a normal weight (all p-values < 0.001). Dietary habits did not noteworthy differ by area of living, that is, urban versus rural, of participants in both sexes. In addition, no noticeable differences in the values of the KIDMED index were found among all regions of Greece, with the highest values in Attica and Crete in both sexes.

CONCLUSIONS

Because Greek schoolchildren do not fully adopt the traditional cardio-protective Mediterranean diet, it could be helpful to provide certain recommendations, especially for adolescents, to decrease the risk for future adverse health consequences.

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

BACKGROUND

Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories.

METHODS

We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5-19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For school-aged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median).

FINDINGS

From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness.

INTERPRETATION

The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesity.

FUNDING

UK Medical Research Council, UK Research and Innovation (Research England), UK Research and Innovation (Innovate UK), and European Union.

Diminishing benefits of urban living for children and adolescents' growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1-6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5-19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m-2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.

European fitness landscape for children and adolescents: updated reference values, fitness maps and country rankings based on nearly 8 million test results from 34 countries gathered by the FitBack network

OBJECTIVES

(1) To develop reference values for health-related fitness in European children and adolescents aged 6-18 years that are the foundation for the web-based, open-access and multilanguage fitness platform (FitBack); (2) to provide comparisons across European countries.

METHODS

This study builds on a previous large fitness reference study in European youth by (1) widening the age demographic, (2) identifying the most recent and representative country-level data and (3) including national data from existing fitness surveillance and monitoring systems. We used the Assessing Levels of PHysical Activity and fitness at population level (ALPHA) test battery as it comprises tests with the highest test-retest reliability, criterion/construct validity and health-related predictive validity: the 20 m shuttle run (cardiorespiratory fitness); handgrip strength and standing long jump (muscular strength); and body height, body mass, body mass index and waist circumference (anthropometry). Percentile values were obtained using the generalised additive models for location, scale and shape method.

RESULTS

A total of 7 966 693 test results from 34 countries (106 datasets) were used to develop sex-specific and age-specific percentile values. In addition, country-level rankings based on mean percentiles are provided for each fitness test, as well as an overall fitness ranking. Finally, an interactive fitness platform, including individual and group reporting and European fitness maps, is provided and freely available online (www.fitbackeurope.eu).

CONCLUSION

This study discusses the major implications of fitness assessment in youth from health, educational and sport perspectives, and how the FitBack reference values and interactive web-based platform contribute to it. Fitness testing can be conducted in school and/or sport settings, and the interpreted results be integrated in the healthcare systems across Europe.

A Modified Mediterranean Diet Improves Fasting and Postprandial Glucoregulation in Adults with Overweight and Obesity: A Pilot Study

The ideal lifestyle intervention to battle both obesity and diabetes is currently unknown. The aim of this pilot uncontrolled intervention trial was to assess the effect of a modified Mediterranean diet (MedDiet) on weight loss and glucoregulation among overweight/obese adults. Eleven men and women with overweight/obesity, aged 37 ± 12 years, participated in a free-living intervention until 10% weight loss was achieved. Participants followed an individualized MedDiet high in monounsaturated fat and protein with decreased carbohydrate and saturated fat contents. Physical activity and dietary intake were monitored with pedometers and food records, respectively. Upon weight loss achievement, anthropometric measurements, blood metabolic profiles and individual responses to oral glucose and mixed-meal tests were evaluated pre- and post-intervention. The results showed significant ameliorations in body fat, waist circumference and leptin levels (p < 0.01), with concomitant increases in adiponectin-leptin ratios (p < 0.001). Glucoregulation was significantly improved according to glucose and insulin responses, homeostatic model assessment of insulin resistance indices and postprandial insulin sensitivity indices (p < 0.05). In conclusion, the modified Mediterranean diet may induce significant improvements in body composition, adipocytokine profile and glucose metabolism in overweight/obese individuals. Notably, ameliorated glycemia and increased insulin sensitivity may be retained even at postprandial level, irrespective of the meal consumed.

Adherence to the Mediterranean Diet and Successful aging in Greeks living in Greece and abroad: the epidemiological Mediterranean Islands Study (MEDIS)

Background: Whether older immigrant populations from the Mediterranean region, continue to follow the MD long after they immigrated is not known. Aim: Compare adherence to the MD and successful aging levels between Greeks living in Greece (GG) and Greeks living abroad (GA). Methods: Anthropometrical, clinical, psychological, sociodemographic, dietary and lifestyle parameters were assessed in a cross-sectional manner in a sample of 252 GG and 252 GA. Mediterranean Diet Score (MedDietScore range 0-55) was used to assess adherence to the MD. Successful aging was evaluated with the validated successful aging index (SAI range 0-10). Results: GA presented higher adherence to MD (p < 0.001); they were consuming significantly more cereals, legumes, vegetables, and fruits compared to GG. GG consumed significantly more dairy (3.8 ± 2.9 vs. 1.9 ± 2.2, p < 0.001) and potatoes (2.4 ± 1.6 vs. 1.9 ± 1.5, p < 0.001) compared to GA. Meat (p = 0.27), poultry (p = 0.72), fish (p = 0.68), olive oil (p = 0.16) and alcohol consumption (p = 0.05) were comparable between the two groups (all p's > 0.05). MedDietScore was positively associated with SAI among both groups after adjusting for possible confounders (0.041 ± 0.014, p = 0.003 GG and 0.153 ± 0.035, p < 0.001 GA). Also, legumes, cereals, fruits and vegetables were found to be beneficial for successful aging. Conclusion: Adherence to the MD is associated with higher levels of successful aging among people of the same genetic background living in different environments. However, traditional dietary habits are gradually abandoned in their native countries, when, at the same time, are considered cultural heritage and preserved accordingly among immigrants.

Endocannabinoids and Heart Rate Variability Alterations after Exposure to Prolonged Intensive Physical Exercise of the Hellenic Navy SEALs

Background: Recent research indicates that both endocannabinoids (eCB) and heart rate variability (HRV) are associated with stress-induced experiences. However, these underlying mechanisms are not elucidated. The present study aims to investigate whether exposure to acute and chronic stress conditions can give rise to measurable changes, both to the peripheral eCB ligands and HRV. Methods: Thirteen candidates under intense preparation for their enlistment in the Hellenic Navy SEALs (HNS) participated in the study. All subjects underwent mental state examination, while HRV variables in time and frequency domain recordings were acquired. Furthermore, at baseline and 30 days after prolonged and intensive physical exercise, hair was collected to measure eCB ligands, such as anandamide (AEA), 2-arachidonoylglycerol (2-AG), and the N-acyl ethanolamine (NAE) molecules: palmitoylethanolamide (PEA) and oleoylethanolamide (OEA). Results: Comparing basal hair concentrations of eCB ligands before and after intense physical exercise, we found that AEA, PEA, and OEA were notably increased, whereas no differences were observed regarding the ligand 2-AG. Furthermore, there were observed associations between the concentrations of peripheral eCB ligands, both at baseline and after the prolonged physical exercise and the time and frequency domains of HRV. Conclusions: These findings suggest that endocannabinoid–HRV interrelations might share a short-term, and long-term adaptability of the changes in self-regulation associated with stress. Further studies will be required to determine the validity of peripheral eCB signaling and HRV as a biomarker for different aspects of the stress response.

The Association of Dietary Habits and Lifestyle Characteristics with Successful Aging among Older Greek Origin Individuals Living in France, Canada, and Greece: The Epidemiological Mediterranean Islands Study (MEDIS)

The aim of the present work was to investigate the association of dietary habits and lifestyle characteristics with successful aging among native Greeks and Greeks of Diaspora (Canada and France). During 2005-2019, 2,434 Greek men and women, living in Greece, in France, and in Canada, over 65 years of age were enrolled voluntarily in the study. Anthropometric, clinical and socio-demographic characteristics, dietary habits, and lifestyle parameters were derived through standard procedures, while successful aging was evaluated using the validated Successful Aging Index (SAI, range 0-10). The SAI of the overall sample was 2.8 ± 1.4. Greeks of Diaspora had higher SAI levels compared to their counterparts in Greece (p's < .001). However, there was no difference between Greeks of Canada and these of France (p > .05). Actually, Greeks of Diaspora had almost 1.9 units higher SAI compared to native Greeks (p < .001). Work and financial status, dietary and lifestyle behaviors (i.e., physical activity, smoking habits), and several clinical characteristics (i.e., history of hypertension and hypercholesterolemia) were statistically different between the three groups (all p's < .05). Greeks of Diaspora had higher SAI levels, probably because of their healthier lifestyle practices, which mainly depend on their traditions and cultural background of their homelands and living conditions in the host countries.

Successful aging and lifestyle comparison of Greeks living in Greece and abroad: the epidemiological Mediterranean Islands Study (MEDIS)

OBJECTIVES

Comparing lifestyle and successful aging between Greeks living in Greece (GG) and Greeks living abroad (GA) using a multidimensional model of successful aging including both biomedical and non-medical components.

METHODS

Anthropometric, clinical, psychological, socio-demographic, dietary and lifestyle parameters were assessed in a random sample of 252 GG and 252 GA. Successful aging was evaluated using the validated successful aging index (SAI range 0-10).

RESULTS

GA had better financial and educational status and scored higher in all social activity parameters (p's < 0.05). GA were more likely to be physically active (p < 0.001), had higher adherence to the Mediterranean diet (p < 0.001) and were less likely to be smoking (p = 0.008). Depression was more evident among GG compared to GA (p < 0.001). GA was aging significantly more successfully than GG (p < 0.001). Men irrespective of location were aging significantly more successfully than women (p < 0.05).

CONCLUSION

Place of residence and personal choices significantly affect the level of healthy aging among people with similar genetic backgrounds.

Human brown fat, adiposity, and cardiometabolic health: New pieces to the puzzle

Brown adipose tissue (BAT) is an emerging target against obesity and its related metabolic diseases. Wibmer et al.1 recently reported that human BAT is associated with a healthier fat distribution and improved cardiometabolic health independent of adiposity and fat distribution.

Students Living in the Islands are Heavier and have Lower Fitness Levels Compared to their Mainland Counterparts; Results from the National Action for Children's Health (EYZHN) Program

Few studies have examined variations in obesity by geographic location in youth and its relation with fitness levels. The present study investigated the association between geographic status (islands versus mainland), excess of body weight and fitness levels among 335.810 schoolchildren (male: 51.3%, 6-18 y, during the school year 2014-2015). Students' anthropometric parameters and fitness levels - accessed via the Euro-fit test - were measured by trained physical education teachers and evaluated according to published norms. Prevalence of overweight (23.0 Vs 21.8%) and obese (10.1 Vs 8.0%) was significantly higher for students living in the islands contrary to their mainland counterparts. A significant difference was also observed for centrally obese children (33.5 Vs 28.2%). Except for speed test .408), in all other four fitness tests, the students from the islands presented significantly lower performance (≤25^th percentile of published age- and sex-specific normative values) versus their mainland counterparts. Boys and girls living in the islands had 48% and 37% increased odds of low physical fitness (as a total), respectively, compared to their mainland counterparts. Likewise, children living in islands presented increased odds of being overweight or obese by 19% and 15% in boys and girls, respectively, as compared to those living in the mainland. Increased general and abdominal adiposity have a direct negative impact on students' performance in Physical Fitness tests. Our data highlight the problem of excessive body weight that children living in rural areas, face.

Screen time and its effect on dietary habits and lifestyle among schoolchildren

OBJECTIVE

The aim of the study was to determine the associations between recreational screen time and dietary habits and lifestyle factors in a representative sample of schoolchildren.

METHODS

Observational, cross-sectional study data were derived from 177,091 children aged 8 to 17 years participating in a health survey. Recreational screen time, physical activity (PA), and sleeping hours were assessed through self-completed questionnaires. Dietary habits were evaluated via the Mediterranean Diet Quality Index for children and adolescents (KIDMED) test. Anthropometric and physical fitness (PF) estimations were obtained by trained investigators.

RESULTS

Binary logistic regression comparisons between screen time levels (e.g. < 2 vs. ≥ 2 - < 3 h/d, < 2 vs. ≥ 3 - < 4 h/d and < 2 vs. ≥ 4 h/d) and dietary habits showed that the longer the screen time the increased the odds of unhealthy dietary habits such as skipping breakfast, consuming fast food frequently, and eating sweets frequently, and the decreased the odds of healthy dietary habits such as consuming a second fruit every day, consuming fresh or cooked vegetables or/and fish regularly, in both genders, after adjusting for several covariates. Furthermore, the longer the screen time the increased the odds of total and central obesity, insufficient sleep (< 8-9 h/d), and inadequate PA, and the decreased the odds of healthy PF.

CONCLUSIONS

The longer the screen time the unhealthier dietary habits and lifestyle profile among schoolchildren, after adjusting for several covariates.

Exclusive olive oil consumption was favorably associated with metabolic indices and lifestyle factors in schoolchildren

BACKGROUND AND AIM

Olive oil consumption has been suggested to favorably impact children's health. The present study aimed to identify possible associations between exclusive olive oil consumption and metabolic indices and lifestyle factors.

METHODS AND RESULTS

Cross-sectional, observational study. Population data derived from a health survey on a sample of 177 091 children aged 8-17 years. Olive oil consumption and dietary habits were evaluated using questionnaires (KIDMED index). Anthropometric and physical fitness measurements were obtained by trained investigators. Physical activity (PA) status, screen time and sleeping habits were assessed through self-completed questionnaires. Exclusive olive oil consumption decreased the odds of obesity and increased the odds of healthy cardiorespiratory fitness (CRF) by 15% (95% confidence interval (CI): 0.75-0.95) and 13% (95% CI: 1.04-1.22), respectively, after adjusting for several covariates. Moreover, exclusive olive oil consumption was associated with increased odds of having sufficient dietary habits (average/optimal adherence to the Mediterranean Diet) by almost four times (95% CI: 3.65-4.45) and decreased odds of insufficient sleep (<8-9 h/d) and increased screen time (>2 h/d) by 20% (95% CI: 0.73-0.87) and 40% (95% CI: 0.48-0.72), respectively.

CONCLUSIONS

Exclusive olive oil consumption was associated with metabolic indices such as obesity and CRF and a healthy lifestyle profile. The exclusive consumption of olive oil as part of a balanced MD does seem to provide favorable health benefits and should be further promoted.

Schoolteachers' Nutrition Knowledge, Beliefs, and Attitudes Before and After an E-Learning Program

OBJECTIVE

Το explore teachers' nutrition knowledge, beliefs, and attitudes and to examine the effectiveness of an electronic learning (e-learning) program in teachers' nutrition knowledge.

DESIGN

Cross-sectional and experimental design.

SETTING

The study took place in Greece, while schoolteachers were invited by e-mail.

PARTICIPANTS

Teachers of primary and secondary education, with no exclusion criteria, were enrolled in the study between March, 2015 and 2016.

MAIN OUTCOME MEASURES

Schoolteachers' nutrition knowledge, beliefs, and attitudes.

INTERVENTION

Teachers completed a 36-item nutrition questionnaire and then a subgroup participated in an e-learning program. After the intervention, teachers completed the same questionnaire.

ANALYSIS

Principal component analysis and multivariate logistic regression were used for data analysis.

RESULTS

A total of 1,094 teachers completed the questionnaire; 619 participated in the e-learning program. Teachers showed moderate nutrition knowledge scores (ie, 65% correct answers) before the intervention, whereas their attitudes regarding acting as role models and their belief in the importance of the role of nutrition were associated with 74% (odds ratio, 1.28; 95% confidence interval, 1.13-1.45) and 79% (odds ratio, 1.21; 95% confidence interval, 1.07-1.37) increased possibility of having good nutrition knowledge, respectively. The e-learning program was effective in strengthening teachers' nutrition knowledge (P < .001) and improving their beliefs and attitudes (P < .05).

CONCLUSIONS AND IMPLICATIONS

Future research is needed to validate the current results, which can be used to design and implement similar educational programs to teachers as a means of creating health-promoting schools.

Validity and Reliability of the New Portable Metabolic Analyzer PNOE

Assessment of the oxygen and carbon dioxide content of expired air during exercise is critical for determining cardiorespiratory status. The purpose of this study was to compare the new portable metabolic analyzer PNOE with COSMED – Quark CPET, a previously validated stationary metabolic cart.

Methods: A total of 22 subjects (17 male and 5 female) aged 32.3 ± 11.1 years took part in the study. Breath by breath gas exchange was measured by both devices during a four-stage incremental protocol on a cycle ergometer. On a separate day, 10 participants repeated the trial to assess the reliability of the PNOE metabolic cart.

Results: Strong correlations were obtained in VO₂ (r = 0.98, p < 0.001), VCO₂ (r = 0.98, p < 0.001), VE (r = 0.98, p < 0.001), and RQ (r = 0.91, p < 0.001), between the two devices. Bland-Altman plots revealed a mean difference of 34.0 ± 118 ml/min and 36.4 ± 110 ml/min in VO₂ and VCO₂ analysis, respectively. There were no significant differences in VO₂, VCO₂, VE, or RQ between the two devices. Intraclass correlation coefficient was high between the two trials for VO₂ (r = 0.98, p < 0.001), VCO₂ (r = 0.98, p < 0.001), VE (r = 0.99, p < 0.001), and RQ (r = 0.93, p < 0.001).

Conclusions: Our data indicate that the portable metabolic cart PNOE can accurately determine respiratory gases over a wide range of exercise intensities, in healthy individuals, in a controlled laboratory setting.

The Association between Green and Black Tea Consumption on Successful Aging: A Combined Analysis of the ATTICA and MEDiterranean ISlands (MEDIS) Epidemiological Studies

Tea is one of the most-widely consumed beverages in the world with a number of different beneficial health effects, mainly ascribed to the polyphenolic content of the tea catechins. The aim of this study was to examine the consumption of green, black, or no tea, in relation to the previously validated successful ageing index (SAI; higher values "healthier" ageing) in a combined analysis of adults aged >50 years old from the ATTICA (n = 1128 adults from Athens, Greece metropolitan area) and the MEDiterranean Islands Study (MEDIS) (n = 2221 adults from various Greek island and Mani) studies. After adjusting for age, sex, smoking, and coffee consumption, green tea was positively associated with SAI (b ± SE: 0.225 ± 0.055, p < 0.001), while black tea was negatively associated with SAI (unstandardized b coefficient ± Standard error: -0.807 ± 0.054, p < 0.001). Green tea (vs black tea) consumption, had higher odds of a SAI of over 3.58 out of 10 (OR: 1.77, 95% CI: 1.38-2.28). Green tea consumption was also associated with higher levels of physical activity (p < 0.001) and reduced likelihood of hypertension (p = 0.006) compared with black tea. Two possible mechanisms are that green tea possesses high levels of catechins such as (-)-epigallocatechin 3-gallate and l-theanine compared with black tea. Therefore, the present analysis supports both the role of green tea constituents in successful ageing, as well as its role as an important component of an overall healthy diet in adults aged 50 years and over from these two epidemiological studies.

Association of cardiorespiratory fitness levels with dietary habits and lifestyle factors in schoolchildren

This study examined the association between cardiorespiratory fitness (CRF) levels and lifestyle factors in a representative sample of Greek schoolchildren. In 2015, a health survey was carried out in 177 091 participants 8–17 years of age. Dietary habits, sleeping hours, physical activity (PA), and sedentary activities were assessed through self-completed questionnaires. CRF was evaluated with a 20-m shuttle run test. Insufficient dietary habits were greater in boys and girls classified as having low CRF than in their peers with healthy CRF. Skipping breakfast (odds ratio (OR), 0.82; 95% confidence interval (CI) 0.79–0.85), fast food consumption (OR, 0.70; 95% CI 0.68–0.72), and regular sweet intake (OR, 0.79; 95% CI 0.76–0.82) decreased the odds of having a healthy CRF level. An increase in age by 1 year (OR, 0.71; 95% CI, 0.70–0.72), overweight/obesity (OR, 0.30; 95% CI 0.29–0.31), and insufficient sleep duration (OR, 0.74; 95% CI 0.72–0.76) decreased the odds of a healthy CRF level, whereas sufficient dietary habits and adequate PA levels increased a participant’s odds of having a healthy CRF level, by 48% and 40%, respectively. Although the mechanisms via which CRF may be influenced by dietary habits remain unclear, health policy-makers should consider opportunities for improving both CRF and dietary habits.

Concomitant Associations between Lifestyle Characteristics and Physical Activity Status in Children and Adolescents

BACKGROUND

To examine the concomitant associations between physical activities (PA) and lifestyle factors in a representative sample of children and adolescents.

STUDY DESIGN

Cross-sectional, observational study.

METHODS

Population data were derived from a school-based health survey carried out in 2015 on 177,091 (51% boys) Greek children aged 8 to 17 yr old. PA, sedentary activities and sleeping habits were assessed through self-completed questionnaires. Dietary habits were evaluated using the Mediterranean Diet Quality Index for children and adolescents. Anthropometric and physical fitness measurements were obtained by trained investigators. Logistic regression models were estimated and adjusted for relevant covariates.

RESULTS

More boys as compared to girls (65.1% vs. 50.7%, P<0.001) and children than adolescents (59.8% vs. 52.8%, P<0.001) met the recommendations for PA. Frequent fast food consumption and skipping breakfast were associated with inadequate PA levels. In the whole population, sufficient dietary habits, sufficient (&gt;8-9 h/d) sleeping and accepted screen time increased the participant's odds of adequate PA levels by 38% (95% CI: 1.32, 1.44), 5% (95% CI: 1.01, 1.09) and 21% (95% CI: 1.16, 1.26), respectively, while, overweight/obese and central obesity decreased the odds of adequate PA levels by 7% and 5%, respectively, after adjusting for several covariates. Participants with combination of healthy aerobic fitness/dietary habits/screen time had 60% increased odds for adequate PA levels than those with unhealthy choices.

CONCLUSION

Healthy aerobic fitness, dietary habits and screen time were strongly associated with PA status among children. The results support the development of interventions to help children adopt a healthy lifestyle.

The Effect of Exclusive Olive Oil Consumption on Successful Aging: A Combined Analysis of the ATTICA and MEDIS Epidemiological Studies

The consumption of dietary fats, which occur naturally in various foods, poses important impacts on health. The aim of this study was to elucidate the association of exclusive use of olive oil for culinary purposes with successful aging in adults aged >50 years old and residing in Greece. Use of olive oil in food preparation and bio-clinical characteristics of the Greek participants enrolled in the ATTICA (n = 1128 adults from Athens metropolitan area) and the MEDiterranean Islands Study (MEDIS) (n = 2221 adults from various Greek islands and Mani) studies, were investigated in relation to successful aging (SA). Participants were divided into the following three categories: (a) no olive oil consumption; (b) combined consumption of olive oil and other dietary fats; and (c) exclusive olive oil consumption. The SA was measured using the previously validated successful aging index (SAI). After adjusting for age, sex, and smoking habits, combined consumption of olive oil and other fats (vs. no olive oil use) was not significantly associated with SAI levels (p = 0.114). However, exclusive olive oil intake (vs. no use of olive oil) was significantly associated with SAI (p = 0.001), particularly among those aged older than 70 years. Therefore, the exclusive consumption of olive oil, as opposed to either combined or no olive oil consumption, beneficially impacts successful aging, particularly among individuals over 70 years of age. Primary public health prevention strategies should seek to encourage the enhanced adoption of such dietary practices in order to promote healthy aging and longevity.

Exclusive Breastfeeding Is Favorably Associated with Physical Fitness in Children

Objective: To examine the potential association between exclusive breastfeeding and its duration on physical fitness (PF) components during childhood. Materials and Methods: A random sample of 5,125 dyads children and their mothers was evaluated. With the use of a standardized questionnaire, telephone interviews were carried out for the collection of maternal lifestyle factors (e.g., breastfeeding and its duration, etc.). Data from five PF tests (e.g., vertical jump, standing long jump, small ball throw, 30-m sprint, and 20-m shuttle run) were used to assess lower and upper body strength, speed, and cardiorespiratory fitness (CRF). Linear and logistic regression models were estimated and adjusted for children's body mass index (BMI) and birth weight, and parental factors (prepregnancy BMI, gestational weight gain, gestational age, pregnancy in vitro, parity before, and educational level). Results: Among boys, exclusive breastfeeding was favorably associated with CRF (b = 0.07), lower body strength (b = 0.41), upper body strength (b = 0.10), and speed (b = -0.11). Also, among girls, we found a favorable association between exclusive breastfeeding and CRF (b = 0.07), lower body strength (b = 0.47), upper body strength (b = 0.10), and speed (b = -0.11). All of the associations remained significant after adjusting for several potential confounders. With the exception of speed test in girls, children who were exclusively breastfed ≥6 months had 10-40% increased odds for average/high performances in PF tests in comparison with those who were breastfed <1 month. Conclusions: Exclusive breastfeeding ≥6 months had a favorable influence on PF test performances in childhood. It seems that exclusive breastfeeding could play a significant role in children's future health.

Propranolol and Oxandrolone Therapy Accelerated Muscle Recovery in Burned Children

INTRODUCTION

Severe burns result in prolonged hypermetabolism and skeletal muscle catabolism. Rehabilitative exercise training (RET) programs improved muscle mass and strength in severely burned children. The combination of RET with β-blockade or testosterone analogs showed improved exercise-induced benefits on body composition and muscle function. However, the effect of RET combined with multiple drug therapy on muscle mass, strength, cardiorespiratory fitness, and protein turnover are unknown. In this placebo-controlled randomized trial, we hypothesize that RET combined with oxandrolone and propranolol (Oxprop) will improve muscle mass and function and protein turnover in severely burned children compared with burned children undergoing the same RET with a placebo.

METHODS

We studied 42 severely burned children (7-17 yr) with severe burns over 30% of the total body surface area. Patients were randomized to placebo (22 control) or to Oxprop (20) and began drug administration within 96 h of admission. All patients began RET at hospital discharge as part of their standardized care. Muscle strength (N·m), power (W), V˙O2peak, body composition, and protein fractional synthetic rate and fractional breakdown rate were measured pre-RET (PRE) and post-RET (POST).

RESULTS

Muscle strength and power, lean body mass, and V˙O2peak increased with RET in both groups (P < 0.01). The increase in strength and power was significantly greater in Oxprop versus control (P < 0.01), and strength and power was greater in Oxprop over control POST (P < 0.05). Fractional synthetic rate was significantly higher in Oxprop than control POST (P < 0.01), resulting in improved protein net balance POST (P < 0.05).

CONCLUSIONS

Rehabilitative exercise training improves body composition, muscle function, and cardiorespiratory fitness in children recovering from severe burns. Oxprop therapy augments RET-mediated improvements in muscle strength, power, and protein turnover.

Association of Exclusive Breastfeeding with Risk of Obesity in Childhood and Early Adulthood

OBJECTIVE

To explore the effects of exclusive breastfeeding and its duration on the development of childhood and early adulthood obesity.

MATERIALS AND METHODS

A random sample of 5,125 dyad children and their mothers was extracted from a national database. With the use of a standardized questionnaire, telephone interviews were carried out for the collection of maternal lifestyle factors (e.g., breastfeeding). The body mass index was determined based on International Obesity Task Force criteria. Body weight and height of the offspring at the age of 8 was calculated from measurements derived from the national database, while the corresponding body measurements at early adulthood were self-reported.

RESULTS

Mothers who had breastfed or exclusively breastfed ≥6 months were 22.4% and 15.2%, respectively. Exclusive breastfeeding ≥6 months (versus never) was associated with a lower risk of overweight in childhood (8 years old; odds ratio [OR] = 0.89; 95% confidence interval [95% CI], 0.82-0.96) and adolescence/adulthood (15-25 years old; OR = 0.83; 95% CI, 0.68-0.97). Also, exclusive breastfeeding ≥6 months (versus never) was associated with a decreased risk of childhood and adolescence obesity by 30% (95% CI, 0.54-0.91) and 38% (95% CI, 0.40-0.83), respectively.

CONCLUSIONS

Exclusive breastfeeding had a favorable influence on offspring's overweight and obesity not only in childhood but also in adolescence/adulthood.

Insufficient Sleep Duration Is Associated With Dietary Habits, Screen Time, and Obesity in Children

STUDY OBJECTIVES

To examine sleep duration and the association between insufficient sleep duration and life- style factors in a representative sample of Greek children and adolescents.

METHODS

Population data derived from a school-based health survey carried out in spring 2015 on 177,091 children (51% male) aged 8 to 17 years (participation rate was approximately 40% of the total population). Dietary habits, sleeping hours (weekdays and weekend), physical activity status, and sedentary activities were assessed through electronic questionnaires completed at school with assistance of teachers. Anthropometric and physical fitness measurements were obtained by physical education teachers.

RESULTS

A greater proportion of males than females (42.3% versus 37.3%, P < .001) and of children compared with adolescents (42.1% versus 32.8%, P < .001) reported insufficient sleep duration. Insufficient sleep duration was associated with unhealthy dietary habits such as skipping breakfast (odds ratio [OR] 1.30, 95% confidence interval [CI] 1.25-1.35), fast-food consumption (OR 1.35, 95% CI 1.29-1.41), and consuming sweets regularly (OR 1.32, 95% CI 1.25-1.39). Insufficient sleep duration was found to be associated with insufficient dietary habits (OR 0.59, 95% CI 0.54-0.64), increased screen time (OR 1.26, 95% CI 1.21-1.31), and being overweight/obese (OR 1.21, 95% CI 1.17-1.25), after adjusting for several covariates.

CONCLUSIONS

Insufficient sleep duration was associated with an unhealthy lifestyle profile among children and adolescents in this study. Results support the development of interventions to help students improve sleep duration.

Adipose tissue uncoupling protein 1 levels and function are increased in a mouse model of developmental obesity induced by maternal exposure to high-fat diet

With brown adipose tissue (BAT) becoming a possible therapeutic target to counteract obesity, the prenatal environment could represent a critical window to modify BAT function and browning of white AT. We investigated if levels of uncoupling protein 1 (UCP1) and UCP1-mediated thermogenesis are altered in offspring exposed to prenatal obesity. Female CD-1 mice were fed a high-fat (HF) or standard-fat (SF) diet for 3 months before breeding. After weaning, all pups were placed on SF. UCP1 mRNA and protein levels were quantified using quantitative real-time PCR and Western blot analysis, respectively, in brown (BAT), subcutaneous (SAT) and visceral (VAT) adipose tissues at 6 months of age. Total and UCP1-dependent mitochondrial respiration were determined by high-resolution respirometry. A Student's t-test and Mann-Whitney test were used (significance: P<0.05). UCP1 mRNA levels were not different between the HF and SF offspring. UCP1 protein levels, total mitochondrial respiration and UCP1-dependent respiration were significantly higher in BAT from HF males (P=0.02, P=0.04, P=0.005, respectively) and females (P=0.01, P=0.04, P=0.02, respectively). In SAT, the UCP1 protein was significantly lower in HF females (P=0.03), and the UCP1-dependent thermogenesis was significantly lower from HF males (P=0.04). In VAT, UCP1 protein levels and UCP1-dependent respiration were significantly lower only in HF females (P=0.03, P=0.04, respectively). There were no differences in total respiration in SAT and VAT. Prenatal exposure to maternal obesity leads to significant increases in UCP1 levels and function in BAT in offspring with little impact on UCP1 levels and function in SAT and VAT.

Mediterranean diet and depression among older individuals: The multinational MEDIS study

BACKGROUND

Depression has been linked to a large and growing economic and societal burden worldwide. In Europe, depression is one of the most frequent mental disorders across all age groups, but particularly in people aged 65 years and over, and higher depressive symptoms have been reported among individuals with chronic diseases (e.g., diabetes and heart disease).

AIM

To evaluate the role of adherence to the Mediterranean diet (MedDiet) in depression in a sample of older people living in the Mediterranean basin.

METHODS

Standard procedures were used to determine socio-demographic, lifestyle, and clinical characteristics of the participants, as well as their dietary habits, and depressive symptoms were evaluated using the Geriatric Depression Scale (GDS). Multi-adjusted logistic and linear regression analyses were carried out to evaluate the associations between participants' characteristics and depression.

RESULTS

Participants classified as having mild or severe depression were less educated and physically active, and more diabetic, and they reported less adherence to the MedDiet. Adherence to the MedDiet was associated with the absence of depression [(OR, 95% CI): 0.65, 0.50-0.85]. In addition, daily tea drinking was also related to the absence of depression [(OR, 95% CI): 0.51, 0.40-0.65].

CONCLUSIONS

Greater adherence to the MedDiet and daily tea drinking seem to have a beneficial effect on depressive symptoms in older adults.

Lifestyle determinants of healthy ageing in a Mediterranean population: The multinational MEDIS study

BACKGROUND

To evaluate modifiable, lifestyle risk factors of cardiovascular disease (CVD) among older adults, across ageing, in the Mediterranean area.

METHODS

During 2005-2017, 3131 individuals from 26 Mediterranean islands of 5 countries, ≥65 years of age, were voluntarily enrolled. Anthropometrical, clinical and socio-demographic characteristics, dietary habits, lifestyle parameters were measured through standard procedures. Analyses were performed by year and across consecutive age groups of the participants.

RESULTS

A decrease in the prevalence of current smoking (p < 0.001), engagement in physical activities (p = 0.001) and participation in social events (p = 0.001) for every year increase in age was found. Moderate alcohol drinking increased through ageing (p = 0.008), whereas adherence to Mediterranean diet remained stable, but adequate (p = 0.90). Trend analysis also revealed that a quadratic (U-shape) function better characterized the association between ageing and total cardiometabolic risk factors burden (p for trend <0.001).

CONCLUSIONS

The gaps in the understanding of factors affecting longevity and healthy ageing remain; public health authorities and stakeholders should focus on the lifestyle determinants of healthy ageing, that seems to be an effective mean for improving older peoples' health.

Current data in Greek children indicate decreasing trends of obesity in the transition from childhood to adolescence; results from the National Action for Children's Health (EYZHN) program

Introduction

The aim of the study is to present the most recent estimates of obesity (total and central) prevalence in Greek children and associated risk factors.

Methods

Population data are derived from a yearly, school-based health survey polled in 2015 on 336,014 (51% boys) children aged 4 to 17 years old from almost 40% of all schools of primary and secondary education in Greece. Anthropometric and physical fitness measurements were obtained by trained investigators. Dietary habits, physical activity status, sedentary activities and sleeping hours were assessed through self-completed questionnaires. The gender and age-specific Body Mass Index (BMI) cut-off points were used in order to define BMI groups.

Results

The prevalence of overweight and obesity in the whole population was 22.2% and 9.0% in boys and 21.6% and 7.5% in girls, respectively. Obesity presented decreasing trends in the transition from childhood to adolescence. Central obesity was diagnosed in 95.3% and 93.5% of the simple obese boys and girls, respectively, in almost two to three of overweight children (68.6% of boys and 64.3% of girls), and in 12% of normal weight children. Age, physical fitness, low adherence to Mediterranean diet, insufficient sleeping hours, inadequate physical activity levels and increased screen time were all associated with higher odds of total and central obesity.

Conclusions

Serious and urgent actions need to be taken from public health policy makers in order not only to prevent a further increase in obesity rates but, more important, to treat obesity and/or the obesity associated co-morbidities.

Poor dietary habits in Greek schoolchildren are strongly associated with screen time: results from the EYZHN (National Action for Children's Health) Program

BACKGROUND/OBJECTIVES

To investigate adherence to the Mediterranean diet (MD) and the relationship between MD and lifestyle factors in a representative sample of Greek school children.

SUBJECTS/METHODS

The data derived from 232,401 (51% boys) children aged 8 to 17 years old who participated in a health survey (2015). Physical fitness (PF) and anthropometric estimations were obtained by trained investigators. Physical activity (PA) status, sedentary activities and sleeping hours were assessed through self-completed questionnaires. Mediterranean diet was evaluated via KIDMED test.

RESULTS

Forty percent of participants presented an optimal adherence to MD (≥8), while one to ten incorporated a low adherence to MD (≤3), in both genders. Participants with optimal adherence to MD presented a more favourable status in anthropometric and lifestyle characteristics. Adjusting for several potential confounders, increased screen time (<2 h/d) augmented odds of low adherence by 135% (95% CI: 2.216-2.491) and 150% (95% CI: 2.346-2.687), in boys and girls, respectively. For each 1-year enlarge in the age of children the odds of low adherence to MD enlarged by almost 11% (95%CI: 1.101-1.138) in both genders, while, boys had almost 6% increased probabilities to the low adherence (95%CI: 1.039, 1.102) than girls. Furthermore, insufficient sleeping hours (>2 h/d) and inadequate PA status were connected to higher odds of low adherence to MD.

CONCLUSIONS

Support a modest adherence to the MD and an enhancement considered necessary to adjust dietary intake to current guidelines. However, screen time presented a strong association with low adherence to MD.

Association of Anthropometric and Lifestyle Parameters with Fitness Levels in Greek Schoolchildren: Results from the EYZHN Program

Objective

The aim of the study was to evaluate physical fitness (PF) and identify its anthropometric and lifestyle determinants in a sample of Greek schoolchildren.

Methods

The study sample consisted of 335,810 schoolchildren (♂: 51.3%, 6–18 years old). Students’ anthropometric parameters and PF levels—assessed via the Eurofit test battery—were measured by trained physical education teachers and evaluated according to the available norms, while their lifestyle habits were assessed through a questionnaire.

Results

In all applied PF tests, students’ performance was negatively associated with the presence of obesity and central obesity, defined through international criteria for body mass index and waist to height ratio, respectively. According to multiple logistic regression analysis, the presence of overweight/obesity [odds ratio (OR): 4.43, 95% confidence interval (CI): 3.98–4.93], low adherence to the MD (KIDMED ≤ 3) (OR: 1.27, 95% CI: 1.09–1.48), and increased time spent in sedentary activities (>2 h per day) (OR: 1.16, 95% CI: 1.03–1.29) were positively associated with poor PF, after adjusting for age and sex. In contrast, for every 1 day increase in the weekly frequency of engagement in athletic activity, the probability of poor PF decreased by 26% (OR: 0.74, 95% CI: 0.72–0.77). In a similar model, the presence of central obesity emerged as an even stronger possible predictor of poor PF (OR: 5.20, 95% CI: 4.66–5.78), compared to the presence of general obesity.

Conclusion

Higher general or abdominal adiposity, as well as the adoption of a low-quality diet and a sedentary lifestyle, is strongly associated with low PF levels during childhood.

Similar Mediterranean diet adherence but greater central adiposity is observed among Greek diaspora adolescents living in Istanbul, compared to Athens

OBJECTIVE

The aim of this case-control study was to compare Mediterranean diet (MD) adherence and anthropometry between Greek diaspora adolescents living in Istanbul and Greek adolescents, inhabitants of Athens.

DESIGN

A total of 206 adolescents (103 from each site), aged 10.0-19.0 years old, all of Greek origin, were recruited from schools in Athens and minority schools in Istanbul, for the present case-control study. Participants at each site were age and sex-matched. Anthropometric measurements were performed, and diet adherence was assessed with the KIDMED score.

RESULTS

Breakfast skipping, decreased dairy and increased commercially baked good/pastries consumption for breakfast, fast-food intake and consumption of several sweets each day was more prevalent in Istanbul, but, on the other hand, students from Athens reported eating fewer fruit, vegetables and nuts. The adoption of unhealthy eating habits in each site was counterbalanced by a more 'healthy' dietary element, resulting in an overall similar MD adherence between both sites. Additionally, although weight status was indifferent between the two cities, higher rates of abdominal obesity were recorded in Istanbul, when the weight-to-height ratio was used for diagnosis.

CONCLUSIONS

Differences in several domains of the KIDMED score were recorded among cities, possibly as results of food availability and prices. However, MD adherence and weight status appeared similar, indicating that the dietary transition and acculturation experienced by the remnants is actually very slow and minimal during the 93 years since population exchange.

Validity of Predictive Equations for Resting Energy Expenditure in Greek Adults

AIM

To examine the validity of published resting energy expenditure (REE) equations in Greek adults, and if indicated, develop new cohort-specific predictive REE equations.

METHODS

Indirect calorimetry and anthropometric data were obtained from 226 adult volunteers of diverse age groups and body mass index ranges (18-60 years, 16.6-67.7 kg·m-2). Measured REE was compared to preexisting prediction equations via correlation, regression, and Bland-Altman analysis. Then, cohort-specific REE equations were developed using curve estimation and nonlinear regression. To reduce type I error, presently derived equations were validated by splitting the sample into a training and validation group.

RESULTS

Preexisting equations over-predicted in-cohort REE. Equations by Livigston and Kohlstadt were most accurate at the individual level (63% accuracy), while formulas by Owen and collaborators elicited highest accuracy at the group level (-1.8% bias). Bland-Altman analysis showed proportional bias for most equations. Currently developed equations showed highest overall accuracy with 70% at the individual and group level (1.0% bias), with small differences between measured and predicted REE values (mean, 95% CI 36 [-15 to 88] kcal·day-1).

CONCLUSION

Data indicate currently developed equations to be the most accurate and valid for estimating REE in Greek adults. Further studies should examine the developed equations in an independent sample.

Prescribed Drinking Leads to Better Cycling Performance than Ad Libitum Drinking

Drinking ad libitum during exercise often leads to dehydration ranging from -1% to -3% of body weight.

PURPOSE

This article aimed to study the effect of a prescribed hydration protocol matching fluid losses on a simulated 30-km criterium-like cycling performance in the heat (31.6°C ± 0.5°C).

METHODS

Ten elite heat-acclimatized male endurance cyclists (30 ± 5 yr, 76.5 ± 7.2 kg, 1.81 ± 0.07 m, V˙O2peak = 61.3 ± 5.2 mL·min·kg, body fat = 10.5% ± 3.3%, Powermax = 392 ± 33 W) performed three sets of criterium-like cycling, which consisted of a 5-km cycling at 50% power max followed by a 5-km cycling all out at 3% grade (total 30 km). Participants rode the course on two separate occasions and in a counterbalanced order, during either ad libitum drinking (AD; drink water as much as they wished) or prescribed drinking (PD; drink water every 1 km to much fluid losses). To design the fluid intake during PD, participants performed a familiarization trial to calculate fluid losses.

RESULTS

After the exercise protocol, the cyclist dehydrated by -0.5% ± 0.3% and -1.8% ± 0.7% of their body weight for the PD and AD trial, respectively. The mean cycling speed for the third bout of the 5-km hill cycling was greater in the PD trial (30.2 ± 2.4 km·h) compared with the AD trial (28.8 ± 2.6 km·h) by 5.1% ± 4.8% (P < 0.05). Gastrointestinal, mean skin, and mean body temperatures immediately after the last hill climbing were greater in the AD compared with the PD trial (P < 0.05). Overall, sweat sensitivity during the three climbing bouts was lower in the AD (15.6 ± 5.7 g·W·m) compared with the PD trial (22.8 ± 3.4 g·W·m, P < 0.05).

CONCLUSION

The data suggested that PD to match fluid losses during exercise in the heat provided a performance advantage because of lower thermoregulatory strain and greater sweating responses.

Anti-Inflammatory Nutrition and Successful Ageing in Elderly Individuals: The Multinational MEDIS Study

BACKGROUND

The role of diet and inflammation in successful ageing is not transparent, and as such, is still being investigated. The aim of the present work was to evaluate the inflammatory potential of dietary habits in the successful ageing of a random sample of older adults living in the Mediterranean basin and who participated in the MEDIS (MEDiterranean ISlands) study.

METHODS

During 2005-2016, 3,128 older adults (aged 65-100 years) from 24 Mediterranean islands and the rural Mani region (Peloponnesus) of Greece were enrolled in the study. A multidimensional successful ageing index consisting of 10 components was employed. A validated and reproducible Food Frequency Questionnaire (FFQ) was used to evaluate the dietary habits of the older adults. A nutrition anti-inflammatory (NAI) score based on the participants' specific dietary habits was assessed.

RESULTS

Participants with high NAI scores (proinflammatory nutrition) had a higher prevalence of hypercholesterolemia and lower levels of successful ageing. After adjusting for several confounders, the NAI score was associated with successful ageing (-0.03, 95% CI -0.5 to -0.006). Stratified analysis by gender and advanced age revealed heterogeneity in the NAI score, predicting successful ageing.

CONCLUSIONS

The inflammatory potential of nutrition was reported as an important factor for successful ageing, suggesting that further research is needed on the role of anti- and proinflammatory dietary habits in healthy and successful ageing.

Brown adipose tissue is associated with systemic concentrations of peptides secreted from the gastrointestinal system and involved in appetite regulation

OBJECTIVE

Brown adipose tissue (BAT) has been proposed as a potential therapeutic target against obesity and its related metabolic conditions. Data from studies in rodents support a cross talk between BAT and other distal tissues. The relation between BAT and peptide hormones secreted from the gastrointestinal system (GI) and involved in appetite regulation is not known in humans.

DESIGN

We studied 18 men during thermoneutral conditions and mild non-shivering cold exposure (CE).

METHODS

2-Deoxy-2-(¹⁸F)fluoro-d-glucose positron emission tomography-computed tomography scans were conducted after mild cold to measure BAT volume. Fasting serum concentration of GI-secreted peptides and peptides involved in appetite regulation were measured during thermoneutral conditions and mild CE.

RESULTS

During thermoneutral conditions, BAT volume was associated with lower serum concentration of leptin (P = 0.006), gastric inhibitory polypeptide (P = 0.016) and glucagon (P = 0.048) after adjusting for age and body fat percent. CE significantly decreased serum leptin (P = 0.004) and glucagon concentration (P = 0.020), while cold-induced BAT activation was significantly associated with lower serum ghrelin concentration (P = 0.029).

CONCLUSIONS

BAT is associated with systemic concentrations of GI-secreted peptides and peptides involved in appetite regulation, suggesting a potential cross talk between BAT and the enteropancreatic axis. Further studies are needed to elucidate the potential link of BAT with the postprandial levels of appetite-regulating peptides and the putative role of BAT in appetite regulation in humans.

Is car use related with successful aging of older adults? Results from the multinational Mediterranean islands study

PURPOSE

The aim of the present work was to evaluate the relation between car use and the level of successful aging of a random sample of older adults living in the Mediterranean basin.

METHODS

During 2005-2011, 2749 older (aged 65-100 years) from 22 islands and the rural Mani region (Peloponnesus) of Greece were voluntarily enrolled in the Mediterranean islands cross-sectional study. Sociodemographics, medical conditions, and dietary and lifestyle habits were derived throughout standard procedures. Car use was recorded with a standard binary question. A successful aging index ranging from 0-10 was used.

RESULTS

Older adults who used a car on regular basis had significantly higher levels of successful aging, as well as less prevalence of obesity and hypertension while were more physically active (P < .001). After adjusting for several confounders car use was still positively related with elderly islander's successful aging level (beta coefficient [95% confidence interval]: 0.65 [0.54-0.77]).

CONCLUSIONS

In conclusion, the activity of car use seems to be an indicator of quality of life among older adults, as measured through successful aging.

The metabolic stress response to burn trauma: current understanding and therapies

Major burns provoke a profound stress response, which is unrivalled in terms of its magnitude and duration. Evidence suggests that the pathophysiological stress response to severe burn trauma persists for several years after injury. Thus, there is a pressing need for novel strategies that mitigate this response and restore normal metabolic function in patients with burns. This is the first in a Series of three papers about the care of people with burns. In this paper, we review the current knowledge of the stress response to burn trauma, with a focus on hypermetabolism, muscle wasting, and stress-induced diabetes. We highlight recent developments and important knowledge gaps that need to be pursued to develop novel therapeutic strategies to improve outcomes in burn survivors.

Human and Mouse Brown Adipose Tissue Mitochondria Have Comparable UCP1 Function

Brown adipose tissue (BAT) plays an important role in mammalian thermoregulation. The component of BAT mitochondria that permits this function is the inner membrane carrier protein uncoupling protein 1 (UCP1). To the best of our knowledge, no studies have directly quantified UCP1 function in human BAT. Further, whether human and rodent BAT have comparable thermogenic function remains unknown. We employed high-resolution respirometry to determine the respiratory capacity, coupling control, and, most importantly, UCP1 function of human supraclavicular BAT and rodent interscapular BAT. Human BAT was sensitive to the purine nucleotide GDP, providing the first direct evidence that human BAT mitochondria have thermogenically functional UCP1. Further, our data demonstrate that human and rodent BAT have similar UCP1 function per mitochondrion. These data indicate that human and rodent BAT are qualitatively similar in terms of UCP1 function.

Hypermetabolism and hypercatabolism of skeletal muscle accompany mitochondrial stress following severe burn trauma

Burn trauma results in prolonged hypermetabolism and skeletal muscle wasting. How hypermetabolism contributes to muscle wasting in burn patients remains unknown. We hypothesized that oxidative stress, cytosolic protein degradation, and mitochondrial stress as a result of hypermetabolism contribute to muscle cachexia postburn. Patients (n = 14) with burns covering >30% of their total body surface area were studied. Controls (n = 13) were young healthy adults. We found that burn patients were profoundly hypermetabolic at both the skeletal muscle and systemic levels, indicating increased oxygen consumption by mitochondria. In skeletal muscle of burn patients, concurrent activation of mTORC1 signaling and elevation in the fractional synthetic rate paralleled increased levels of proteasomes and elevated fractional breakdown rate. Burn patients had greater levels of oxidative stress markers as well as higher expression of mtUPR-related genes and proteins, suggesting that burns increased mitochondrial stress and protein damage. Indeed, upregulation of cytoprotective genes suggests hypermetabolism-induced oxidative stress postburn. In parallel to mtUPR activation postburn, mitochondrial-specific proteases (LONP1 and CLPP) and mitochondrial translocases (TIM23, TIM17B, and TOM40) were upregulated, suggesting increased mitochondrial protein degradation and transport of preprotein, respectively. Our data demonstrate that proteolysis occurs in both the cytosolic and mitochondrial compartments of skeletal muscle in severely burned patients. Increased mitochondrial protein turnover may be associated with increased protein damage due to hypermetabolism-induced oxidative stress and activation of mtUPR. Our results suggest a novel role for the mitochondria in burn-induced cachexia.

Satellite cell activation and apoptosis in skeletal muscle from severely burned children

KEY POINTS

Severe burns result in profound skeletal muscle atrophy that hampers recovery. The activity of skeletal muscle stem cells, satellite cells, acutely following a severe burn is unknown and may contribute to the recovery of lean muscle. Severe burn injury induces skeletal muscle regeneration and myonuclear apoptosis. Satellite cells undergo concurrent apoptosis and activation acutely following a burn, with a net reduction in satellite cell content compared to healthy controls. The activation and apoptosis of satellite cells probably impacts the recovery of lean tissue following a severe burn, contributing to prolonged frailty in burn survivors.

ABSTRACT

Severe burns result in profound skeletal muscle atrophy; persistent muscle loss and weakness are major complications that hamper recovery from burn injury. Many factors contribute to the erosion of muscle mass following burn trauma and we propose that an impaired muscle satellite cell response is key in the aetiology of burn-induced cachexia. Muscle biopsies from the m. vastus lateralis were obtained from 12 male pediatric burn patients (>30% total body surface area burn) and 12 young, healthy male subjects. Satellite cell content, activation and apoptosis were determined via immunohistochemistry, as were muscle fibre regeneration and myonuclear apoptosis. Embryonic myosin heavy chain expression and central nucleation, indices of skeletal muscle regeneration, were elevated in burn patients (P < 0.05). Myonuclear apoptosis, quantified by TUNEL positive myonuclei and cleaved caspase-3 positive myonuclei, was also elevated in burn patients (P < 0.05). Satellite cell content was reduced in burn patients, with approximately 20% of satellite cells positive for TUNEL staining, indicating DNA damage associated with apoptosis (P < 0.05). Additionally, a significant percentage of satellite cells in burn patients expressed Ki67, a marker for cellular proliferation (P < 0.05). Satellite cell activation was also observed in burn patients with increased expression of MyoD compared to healthy controls (P < 0.05). Robust skeletal muscle atrophy occurs after burn injury, even in muscles located distally to the site of injury. The activation and apoptosis of satellite cells probably impacts the recovery of lean tissue following a severe burn, contributing to prolonged frailty in burn survivors.

Association between gestational weight gain and risk of obesity in preadolescence: a longitudinal study (1997-2007) of 5125 children in Greece

BACKGROUND

The present study aimed to investigate the association between gestational weight gain (GWG) and birth weight, as well as the body mass index (BMI) status, of children at the ages of 2 and 8 years.

METHODS

Population-based data were obtained from a database of all 7-9-year-old Greek children who attended primary school during 1997-2007. The study sample consisted of 5125 children matched with their mothers, randomly selected according to region and place of residence, and equally distributed (approximately 500 per year) throughout the study period (1997-2007). A standardised questionnaire was applied; telephone interviews were carried out to collect maternal age, BMI status at the beginning and the end of pregnancy and GWG, birth weight of offspring and BMI status at the ages of 2 and 8 years, as well as several other pregnancy characteristics (e.g. pregnancy duration, gestational medical problems, maternal smoking and alcohol consumption habits, and lactation of offspring after pregnancy).

RESULTS

Gestational weight gain was positively associated with the weight status of offspring at all three life stages studied: newborn (birth weight), infant (BMI) and child (BMI) [b = 0.008 (0.001), b = 0.053 (0.009) and b = 0.034 (0.007), respectively, all P < 0.001], after adjusting for maternal age at pregnancy (significant inverse predictor only at age 2 years). The same applied to excessive GWG, as defined by the Institute of Medicine guidelines.

CONCLUSIONS

Excessive GWG was associated with a higher risk of greater infant size at birth and a higher BMI status at the ages of 2 and 8 years. Healthcare providers should encourage women to limit their GWG to the range indicated by the current guidelines.

Fluid Balance During Training in Elite Young Athletes of Different Sports

Although there are many studies demonstrating a high percentage of adult athletes who start exercise in suboptimal hydration state, limited data concerning hydration levels in athletic youth exist. The purpose of this study was to identify the hydration status of elite young athletes of different sports, during a typical day of training. Fifty-nine young elite male athletes from different sports (basketball, gymnastics, swimming, running, and canoeing) participated in the study (age: 15.2 ± 1.3 years; years of training: 7.7 ± 2.0). Hydration status was assessed in the morning, before and immediately after practice. Data collection took place at the same time of the day, with mean environmental temperature and humidity at the time of the measurements at 27.6 ± 0.9° C and 58 ± 8%, respectively. All athletes trained for approximately 90 minutes, and they were consuming fluids ad libitum throughout their practice. Over 89% of the athletes were hypohydrated (urine specific gravity [USG] ≥1.020 mg·dl) based on their first morning urine sample. Pretraining urine samples revealed that 76.3% of the athletes were hypohydrated, whereas a significant high percent remained hypohydrated even after training according to USG values ≥1.020 mg·dl (74.5%) and urine color scale: 5-6 (76.3%). Mean body weight loss during training was -1.1 ± 0.07%. We concluded that the prevalence of hypohydration among elite young athletes is very high, as indicated by the USG and urine color values. The majority of the athletes was hypohydrated throughout the day and dehydrated even more during practice despite fluid availability.

Brown Adipose Tissue Activation Is Linked to Distinct Systemic Effects on Lipid Metabolism in Humans

Recent studies suggest that brown adipose tissue (BAT) plays a role in energy and glucose metabolism in humans. However, the physiological significance of human BAT in lipid metabolism remains unknown. We studied 16 overweight/obese men during prolonged, non-shivering cold and thermoneutral conditions using stable isotopic tracer methodologies in conjunction with hyperinsulinemic-euglycemic clamps and BAT and white adipose tissue (WAT) biopsies. BAT volume was significantly associated with increased whole-body lipolysis, triglyceride-free fatty acid (FFA) cycling, FFA oxidation, and adipose tissue insulin sensitivity. Functional analysis of BAT and WAT demonstrated the greater thermogenic capacity of BAT compared to WAT, while molecular analysis revealed a cold-induced upregulation of genes involved in lipid metabolism only in BAT. The accelerated mobilization and oxidation of lipids upon BAT activation supports a putative role for BAT in the regulation of lipid metabolism in humans.