Sleeping Time, BMI, and Body Fat in Chinese Freshmen and Their Interrelation

Associations of actigraphy-assessed sleep variables with adiposity and serum cardiometabolic outcomes in emerging adults

This study assessed associations of actigraphy-assessed sleep with adiposity and serum cardiometabolic outcomes in emerging adults, and whether sex and race modified these associations. Data on 147 emerging adults (age = 19.4 ± 1.3 years; body mass index = 26.4 ± 7.0 kg m-2 ; 59% female; 65% White) from RIGHT Track Health were used. Actigraphy-based sleep measures included sleep duration, sleep efficiency, sleep timing midpoint, day-to-day sleep duration and sleep timing midpoint variability. Combined sleep duration and sleep timing behaviours were also derived (early-bed/late-rise, early-bed/early-rise, late-bed/late-rise, late-bed/early-rise). Outcomes included body mass index and BodPod-assessed fat mass index, fasting serum leptin, C-reactive protein, and homeostatic model assessment-insulin resistance. Sleep duration was 5.4 h per night. We noted an inverse association between sleep duration and homeostatic model assessment-insulin resistance. The early-bed/early-rise group had greater body mass index, C-reactive protein and homeostatic model assessment-insulin resistance compared with the early-bed/late-rise group (referent). Sex modified associations of sleep efficiency with C-reactive protein; stratified results revealed positive association between sleep efficiency and C-reactive protein in males, but not females. Race modified associations of sleep duration with body mass index and leptin, and of sleep duration variability with C-reactive protein. Stratified analyses revealed inverse associations between sleep duration with body mass index and leptin in Black, multiracial/other race individuals only. Positive association between sleep duration variability and C-reactive protein was noted in White individuals only. Shorter sleep duration, particularly when combined with earlier sleep timing, is associated with greater adiposity and serum cardiometabolic outcomes. Additional studies are needed to assess individual- and contextual-level factors that may contribute to sex and race differences in sleep health and cardiometabolic risk in emerging adults.

Body composition is related to cognitive function among young adults in Ghana

BACKGROUND

A growing body of evidence suggests that obesity can affect cognitive function. However, it is unclear whether this effect is independent of obesity-related comorbidities. This study thus sought to determine the association between body composition and cognitive function of young adults in Ghana with less predisposition to obesity-related comorbidities.

METHODS

A cross-sectional study design was employed, involving 381 participants recruited by simple random sampling. After consenting, participants completed questionnaires that assessed sociodemographic characteristics, along with assessments for anthropometric measures and cognitive function. Analyses for associations were conducted by either Pearson's correlation test or chi-Square test of independence.

RESULTS

Over half (60%) of participants were females and 69.6% were in the first year with a mean age of 20.18 ± 2.52 years. Based on Pearson's correlation test, no significant association was found between Body Mass Index (BMI) and Waist to Hip Ratio (WHR), and Trail Making Test-A and B (TMT-A and TMT-B). Nonetheless, a chi-square test showed a significant association, between BMI and TMT-A (p = 0.01), and WHR and both TMT-A (p = 0.001) and TMT-B (p = 0.02). Weak direct correlations were found between body fat percentage and TMT-A (r = 0.120, p = 0.019) and TMT-B (r = 0.133, p = 0.009). Further, a weak inverse correlation was found between muscle mass and TMT-A (r = - 0.141, p = 0.006) and TMT-B (r = - 0.144, p = 0.005).

CONCLUSION

High body fat, low muscle mass and body fat distribution may have a significant association with cognitive functions and must be considered in obesity interventions. This study provided more insight on the association between BMI and cognitive function and would be helpful in designing new weight management interventions or modifying existing interventions to consider the influence of obesity on cognitive function.

Dietary and Lifestyle Risk Factors of Obesity Among Young Adults: A Scoping Review of Observational Studies

PURPOSE OF REVIEW

Obesity is a growing public health concern worldwide, especially among young adults. This scoping review aims to identify and summarize the current evidence on dietary and lifestyle risk factors associated with obesity among young adults.

RECENT FINDINGS

A scoping review was performed using the PRISMA-ScR guidelines. A systematic search of five electronic databases published from inception to October 2023 was conducted. A total of 46 observational studies met the inclusion criteria and were included in the review. The findings suggest that high intake of energy-dense foods, unhealthy eating habits, poor sleep quality, and increased screen time were significant risk factors for obesity among young adults. In contrast, the association between obesity and sedentary behavior, low physical activity levels, alcohol consumption, and smoking habits was inconclusive. The reviewed evidence suggests that unhealthy dietary habits and lifestyle behaviors are associated with an increased risk of obesity among young adults. The findings highlight the need for further research on these modifiable risk factors to prevent and manage obesity among young adults.

Association between nocturnal sleep duration and the risk of hyperuricemia among Chinese government employees: A cross-sectional study

Objectives

Evidence has shown that nocturnal sleep duration is associated with the risk of hyperuricemia, yet the findings are inconsistent. Thus, we aimed at exploring the association between nocturnal sleep duration and the risk of hyperuricemia in Chinese government employees.

Methods

A total of 10,321 government employees aged 20-60 years were collected from the Cohort Study on Chronic Diseases among Government Employees in Hunan Province, China. Sleep duration was self-reported. And serum uric acid levels >420 μmol/L in men and >360 μmol/L in women were considered hyperuricemia. The association between nocturnal sleep duration and hyperuricemia risk was examined utilizing multivariate logistic regression models. To further examine the connection between nocturnal sleep duration and serum uric acid levels, multiple linear regression analyses were utilized.

Results

The prevalence of hyperuricemia was 17.2%. The results of logistic regression demonstrated that, in contrast to participants whose sleep duration was 7-8 h, those who slept for <7 h had an elevated risk of hyperuricemia (OR = 1.343, 95%CI: 1.126, 1.601). Further stratified analysis revealed that this association was still observed in those without obesity (OR = 1.365; 95%CI: 1.127, 1.655), hypertension (OR = 1.290, 95%CI: 1.054, 1.578), or diabetes mellitus (OR = 1.361, 95%CI: 1.136, 1.631). Multiple linear regression showed that shorter sleep duration (< 7 h) was positively correlated with serum uric acid levels. In comparison to individuals who slept for 7-8 h, those with sleep duration of fewer than 7 h had serum uric acid levels that were 7.231 μmol/L (95% CI: 2.875, 11.588) higher.

Conclusion

Short nocturnal sleep duration (< 7 h) was associated with a higher risk of hyperuricemia, especially in participants without obesity, hypertension, or diabetes mellitus. Besides, short nocturnal sleep duration was related to greater uric acid levels.

Effects of an Intermittent Fasting 5:2 Plus Program on Body Weight in Chinese Adults with Overweight or Obesity: A Pilot Study

To retrospectively review the efficacy of intermittent fasting 5:2 plus program (30% of energy requirements on fast days and 70% of energy requirements on nonfasting days) in Chinese patients with overweight or obesity. This retrospective cohort study evaluated weight loss outcomes of patients treated with 12 weeks weight loss program in clinic. Adults with overweight or obesity participated in intermittent fasting 5:2 plus, daily calorie restriction (70% of energy requirements every day) or daily calorie restriction with meal replacement (70% of energy requirements every day, partly provided with high-protein meal replacement) programs for 12 weeks. The primary objective was to compare the weight loss of three groups. The primary outcome measure was the change in the % total weight loss. A total of 131 patients (35.3 ± 10.1 years; 81.7% female) were included, and the mean weight loss was 7.8 ± 4.4% after 12 weeks. The intermittent fasting 5:2 plus group (n = 42) achieved 9.0 ± 5.3% weight loss, compared with 5.7 ± 3.7% in the daily calorie restriction group (n = 41) (p < 0.001) and 8.6 ± 3.5% in the meal replacement group (n = 48) (p = 0.650). A total of 85.7% of patients in the intermittent fasting 5:2 plus group lost more than 5% body weight, vs. 58.5% in the daily calorie restriction group (p = 0.008), and 45.2% lost more than 10% body weight, vs. 14.6% in the daily calorie restriction group (p = 0.005). No serious adverse events were reported in the three groups. The intermittent fasting 5:2 plus program more effectively led to weight loss than daily calorie restriction in the short-term in Chinese patients with overweight or obesity. A longer-term prospective randomized controlled trial is needed.

Diagnostic test accuracy of waist-to-height ratio as a screening tool for cardiovascular risk in children and adolescents: a meta-analysis

CONTEXT

Waist-to-height ratio (WHtR) is a controversial evaluation index of cardiovascular risk factors (CVRFs) in children and adolescents.

OBJECTIVE

To assess the accuracy of WHtR as a measure to screen for clusters of at least one CVRF (CVRF₁), two CVRFs (CVRF₂), and three CVRFs (CVRF₃) in different ages, sexes, regions and cut-offs.

METHODS

The PubMed, Web of Science, EBSCOhost, Springer, Taylor & Francis Online, Wiley Online Library, Wanfang, and CNKI databases were searched for eligible publications up to June 2021. The QUADAS-2 checklist was used to assess the methodology of the included studies.

RESULTS

Twenty-two studies that evaluated 85281 children and adolescents aged 5-19 years were included in the meta-analysis. The AUSROC values were 0.56 (95% CI: 0.54-0.57), 0.82 (95% CI: 0.81-0.83), and 0.89 (95% CI: 0.89-0.90) for CVRF₁, CVRF₂, and CVRF₃, respectively. Higher AUSROC values were found for adolescents (12-19 years), that is, 0.91 (95% CI: 0.88-0.93), 0.90 (95% CI: 0.87-0.92) for males, and 0.91 (95% CI: 0.90-0.91) for a cut-off of ≥ 0.51 in the identification of CVRF₃.

CONCLUSION

WHtR can be used as an accurate screening tool for CVRF₃ and CVRF₂ in children and adolescents, and it is recommended to select different cut-offs according to different ages, sexes, and regions.

Distribution and Difference of Gastrointestinal Flora in Sheep with Different Body Mass Index

Fat deposition is the key factor affecting the efficiency of animal husbandry production. There are many factors affecting fat deposition, in which the gastrointestinal microbiota plays an important role. Therefore, the body mass index (BMI) was introduced into the evaluation of sheep fat deposition, and the different microbiota and functional pathways of the sheep gastrointestinal tract in different BMI groups were analyzed. We selected 5% of individuals with the highest and lowest BMI from a feed test population (357 in whole group). Microorganisms in 10 sites of the gastrointestinal tract in 36 individuals (18 in each group) were evaluated by 16S rRNA V3−V4 region sequencing. There were differences (p < 0.05) in fat deposition traits between different BMI groups. In the 10 parts of the gastrointestinal tract, the diversity and richness of cecal microflora in the high-BMI group were higher than those in low-BMI Hu sheep (p < 0.05). Principal coordinate analysis (PCoA) showed that there was separation of the cecum between groups, and there were differences in the cecal microbial community. Linear discriminant analysis effect size (LEfSe) showed that most biomarkers were in the cecum. On the basis of an indepth study of cecal microorganisms, 26 different bacterial genera were obtained (p < 0.05). Correlation analysis between them and the characteristics of fat deposition in sheep showed that Colidextribacter, Alloprevotella, and Succenivibrio were positively correlated with fat deposition, while Lachnospiraceae_ND3007_Group was negatively correlated (p < 0.05). The above results show that the cecum may be an important part leading to the difference of BMI in sheep, and its microorganisms may affect the level of fat deposition.

Metabolic rate and substrate oxidation of young males with obesity at the different sleep stages

OBJECTIVE

Insufficient and poor-quality sleep among young adults is closely related to obesity and may impact metabolic processes. The mobilization and use of endogenous substrates during sleep, especially fat oxidation, is essential for energy metabolism. This study investigated whether there are differences in sleep structure, metabolic rate, substrate oxidation, and the respiratory quotient (RQ) between young males with normal weight and obesity according to sleep stages and overnight sleep.

METHODS

Fifteen young males with normal weight and fifteen with obesity posited electrodes of polysomnography (PSG) and slept in the metabolic chamber for estimation of sleep structure, sleep metabolic rate (SMR), carbohydrate oxidation (CHOO), fat oxidation (FATO), and RQ. Fat-free mass (FFM) was measured by bioelectrical impedance analysis.

RESULTS

The sleep period time (p = 0.038) and total sleep time (p = 0.032) were significantly shorter in the obesity group than in the normal-weight group. The obesity group also had a longer sleep latency (p = 0.034) and more sleep-turning events (p = 0.018). CHOO/FFM and the RQ were higher in the obesity group while FATO/FFM was significantly higher in the normal-weight group. FATO/FFM was also higher in the normal-weight group in each sleep stage whereas the RQ was higher in the obesity group (p < 0.05).

CONCLUSIONS

Young males with obesity showed lower fat oxidation and more dominant carbohydrate-derived fuel oxidation than normal-weight during sleep and experienced shorter sleep periods and total sleep time.

Associações entre duração de sono e índices de massa gorda, muscular e corporal em adolescentes de São Luís, Maranhão, Brasil

O objetivo do estudo foi avaliar a associação entre duração de sono e composição corporal em adolescentes. Estudo transversal, com 1.269 adolescentes de 18 e 19 anos da coorte de nascimentos de 1997/1998 de São Luís, Maranhão, Brasil. A duração do sono foi avaliada a partir dos dados registrados por acelerometria. A composição corporal foi avaliada pelo o índice de massa gorda (IMG), índice de massa muscular (IMM) e índice de massa corporal (IMC). Os fatores de confusão foram identificados em gráfico acíclico direcionado no programa DAGitty 3.0. Foram realizadas análises descritivas para todas as variáveis e, posteriormente, regressão linear, com estimativa dos coeficientes de regressão brutos e ajustados, com os respectivos intervalos de 95% de confiança (IC95%). Nos adolescentes do sexo masculino, cada hora a mais de sono associou-se a reduções de 0,30kg/m2 do IMM (IC95%: -0,45; -0,15), de 0,26kg/m2 do IMG (IC95%: -0,48; -0,03) e 0,61kg/m2 do IMC (IC95%: -0,93; -0,30). Nas adolescentes, cada hora a mais de sono associou-se à redução de 0,22kg/m2 do IMM (IC95%: -0,36; -0,07). A maior duração do sono associou-se a menor IMM em ambos os sexos e menor IMG e IMC no sexo masculino, o que evidencia a importância de ter adequadas horas de sono para melhorar os índices de composição corporal.

Sleep, Physical Activity, and Diet of Adults during the Second Lockdown of the COVID-19 Pandemic in Greece

The aim of the present study was to evaluate the possible correlations between sleep, physical activity, and diet in the general population of Greece during the second lockdown due to COVID-19 pandemic. A web-based questionnaire including 28 items was completed by 494 adults (age 31.5 ± 12.4 years). Half of the participants (49.8%) reported good, 44.1% moderate, and 6.1% bad quality of sleep, whereas 17.2% answered that the quality of sleep improved, 56.5% did not change, and 26.3% worsened compared to a normal week. Compared to normal, sleep duration in lockdown increased by 0.24 h (95% CI; 0.13, 0.35; p < 0.001, d = 0.198). More under-weight (32.4%) and obese (34.1%) respondents reported worsened quality of sleep in lockdown compared with normal (25.6%) and overweight participants (22.7%) (p = 0.006, Cramer's φ = 0.191). A small effect for BMI group on sleep duration was observed (p = 0.011, η2 = 0.023), where overweight and obese slept less (-0.44 h and -0.66 h, respectively) than normal weight participants. Subjects with the highest percentage of increased food consumption reported decreased sleep duration (p = 0.012) and worsened sleep quality (p = 0.003). Compared with a normal week, physical activity of a high and moderate intensity decreased for 43.0% and 37.0% of participants, did not change in 32.9% and 36.1% of participants, and increased in 24.1% 26.9%, respectively, whereas walking time decreased in 31.3%, did not change in 27.3%, and increased in 41.5% of participants. Increased high and moderate intensity physical activity was related with an improvement in sleep quality (p < 0.001). Those with decreasing walking time reported the highest percentage of decreased sleep quality (p = 0.006) and worsened sleep quality (p = 0.016). In conclusion, both quality and quantity of sleep were impaired during the second lockdown and the observed changes were associated with diet and physical activity.

Are the factors associated with overweight/general obesity and abdominal obesity different depending on menopausal status?

Rapid modernization in China has impacted the daily lives and health of women, including a rise in obesity. However, little is known about the impact of menopausal status, behavior, and psychosocial factors on the risk of obesity for rural women in China. The aim of this study is to identify risk factors, including demographic information (education, family history of T2DM, menopausal status), obesity-related behavior, and psychosocial factors associated with overweight/general obesity and abdominal obesity. In a cross-sectional study design, participants had their weight, height, and waist circumference measured and completed questionnaires regarding family demographics, obesity-related health behaviors (physical activity, diet, sleep), and psychosocial information (stress, social support, and self-efficacy related to physical activity and healthy diet). A total of 646 women were included in this study; 46.6% were overweight/generally obese, and 48% had abdominal obesity. Postmenopausal women had a higher prevalence of general and central obesity. Regular physical activity decreased the risk for overweight/general obesity and abdominal obesity (OR = .41 and .31, respectively, p = .04) in premenopausal women. Postmenopausal women who had not breastfed their infants and reported moderate/high-stress had a higher risk for overweight/general obesity (OR = 3.93, and 2, respectively) and those who reported less than 6 hours of sleep per day increased their risk for abdominal obesity (OR = 2.08). Different factors associated with obesity were found in Chinese women, depending on menopausal status. Future studies should examine the impact of menopause on a woman’s risk for obesity, as well as develop tailored interventions to improve health, well-being and reduce the risk of obesity.

Sleep disorders related to nutrition and digestive diseases: a neglected clinical condition

Sleep disturbances often result from inappropriate lifestyles, incorrect dietary habits, and/or digestive diseases. This clinical condition, however, has not been sufficiently explored in this area. Several studies have linked the circadian timing system to the physiology of metabolism control mechanisms, energy balance regulation, and nutrition. Sleep disturbances supposedly trigger digestive disorders or conversely represent specific clinical manifestation of gastrointestinal (GI) diseases. Poor sleep may worsen the symptoms of GI disorders, affecting the quality of life. Conversely, short sleep may influence dietary choices, as well as meal timing, and the circadian system drives temporal changes in metabolic patterns. Emerging evidence suggests that patients with inappropriate dietary habits and chronic digestive disorders often sleep less and show lower sleep efficiency, compared with healthy individuals. Sleep disturbances may thus represent a primary symptom of digestive diseases. Further controlled trials are needed to fully understand the relationship between sleep disturbances, dietary habits, and GI disorders. It may be also anticipated that the evaluation of sleep quality may prove useful to drive positive interventions and improve the quality of life in a proportion of patients. This review summarizes data linking sleep disorders with diet and a series of disease including gastro-esophageal reflux disease, peptic disease, functional gastrointestinal disorders, inflammatory bowel diseases, gut microbiota alterations, liver and pancreatic diseases, and obesity. The evidence supporting the complex interplay between sleep dysfunction, nutrition, and digestive diseases is discussed.