Background: Obesity is increasing in parallel with greater all-day food availability. The latter may promote meal irregularity, dysregulation of the energy balance, and poor metabolic health. Objective: We investigated the effect of meal irregularity on the thermic effect of food (TEF), lipid concentrations, carbohydrate metabolism, subjective appetite, and gut hormones in healthy women. Design: Eleven normal-weight women (18-40 y of age) were recruited in a randomized crossover trial with two 14-d isoenergetic diet periods (identical foods provided and free living) that were separated by a 14-d habitual diet washout period. In period 1, participants followed a regular meal pattern (6 meals/d) or an irregular meal pattern (3-9 meals/d), and in period 2, the alternative meal pattern was followed. Before and after each period, when participants were fasting and for 3 h after intake of a test drink, measurements were taken of energy expenditure, circulating glucose, lipids (fasting only), insulin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and ghrelin. An ad libitum test meal was offered. Subjective appetite ratings were assessed while fasting, after the test drink, after the ad libitum meal, and during the intervention. Continuous interstitial glucose monitoring was undertaken for 3 consecutive days during each intervention, and the ambulatory activity pattern was recorded (ambulatory energy expenditure estimation). Results: Regularity was associated with a greater TEF (P , 0.05) and a lower incremental area under the curve (iAUC) for glucose after intake of the test drink (over 3 h) and, for some identical meals, during the 2 interventions (over 90 min) (day 7: after breakfast; day 9: after lunch and dinner). There was no difference between treatments for the test-drink gut hormone response. A time effect was noted for fasting GLP-1, fasting PYY, PYY responses, and hunger-rating responses to the test drink (P , 0.05). Lower hunger and higher fullness ratings were seen premeal and postmeal during the regular period while subjects were free living. Conclusion: Meal regularity appears to be associated with greater TEF and lower glucose responses, which may favor weight management and metabolic health. This trial was registered at clinicaltrials.gov as NCT02052076.Am J Clin Nutr 2016;104:21-32.

ObjectiveAdequate sleep is an important factor for maintaining good health among children. However, there have been few studies reporting on the association of sleep duration with breakfast intake frequency. This study examined the prevalence of nocturnal sleep duration among Saudi children and its association with breakfast intake, screen time, physical activity levels and socio-demographic variables.MethodsA multistage stratified cluster random sampling technique was used to select 1051 elementary school children in Riyadh. Weight and height were measured and body mass index was computed. The sleep duration, daily breakfast intake frequency, socio-demographic and lifestyle behaviors were assessed using a specifically designed self-reported questionnaire filled by the children’s parents.ResultsOver 71% of the Saudi school children did not attain the recommended sufficient sleep duration at night. Results of logistic regression analysis, adjusted for confounders, exhibited significant associations between longer sleep duration and younger age (aOR=1.12, p=0.046), being female (aOR=1.39, p=0.037), higher father educational levels, daily breakfast intake (aOR=1.44, p=0.049) and lower screen time (aOR for >2 hrs/day=0.69, p=0.033). However, no significant (p> 0.05) association was found for mother education, family income, number of family member in the house, overweight/obesity, or physical activity levels.ConclusionThe prevalence of insufficient nocturnal sleep among Saudi children was high. Insufficient sleep was associated with breakfast and several important socio-demographic and lifestyle behaviors. The findings of this study support the development of interventions to prevent insufficient sleep and help Saudi children improve their sleeping habits.

Background Breakfast is an important meal that provides essential nutrients and energy. However, few comprehensive studies have reported breakfast habits and related behaviors among Saudi children. This study investigated breakfast consumption patterns and the associations of socio-demographic variables with daily breakfast intake among Saudi children. Methods A multistage stratified cluster random sampling technique was used to select 1051 elementary school boys and girls in Riyadh. Body weight and height were measured and body mass index (BMI) was computed. The breakfast eating habits and behaviors were assessed using a specifically designed self-reported questionnaire that was completed by the children’s parents. Results More than 79% of children skipped daily breakfast, with no significant sex difference. Children in private schools consumed breakfast more frequently than those attending public schools. Multivariate analyses showed that boys in private schools had a significantly higher intake of breakfast than that in boys in public schools, yet, boys in public schools had significantly higher BMI than boys in private schools. Using logistic regression while adjusting for confounders showed insignificant effect for parent education. Among breakfast eaters, spread cheese sandwiches were consumed most frequently, followed by fried egg sandwiches and breakfast cereals. Full-fat milk, tea with milk, water, and fruit juice were the most consumed drinks. Girls consumed significantly more fresh fruits during breakfast than did boys. Mothers prepared breakfast at home most of the time (84.5%). Parents appeared mostly satisfied with the breakfast consumed by their child at home and placed high importance on breakfast compared to lunch or dinner. Conclusions The proportion of school children who ate daily breakfast at home was low, which may have implications for children’s school performance. Effort is needed to promote daily breakfast consumption among Saudi school children and to introduce appropriate interventions aimed at promoting daily breakfast consumption among Saudi children.

Background: A proportion of cases with repeated abortion are caused by chromosomal abnormality in one of the parents. Several studies have been done to determine the role of chromosomal abnormalities in couples with repeated fetal loss in various countries. None of these studies was done in the Arab Peninsula. Material and Methods: Cytogenetic study was done for 193 consecutive Saudi couples who presented with repeated abortion at the King Khalid University Hospital in Riyadh, Saudi Arabia. Results: We found that the frequency of chromosomal abnormalities was not significantly different from that reported worldwide. The nature of those abnormalities and their relation to the obstetric history of cases were discussed. Approximately 15%-20% of clinically recognizable pregnancies end in spontaneous abortion. Conclusion1,2 The incidence of chromosomal abnormalities in those abortions is as high as 50%.3 A modest but clinically important proportion of spontaneous abortions is caused by a balanced chromosomal aberration in one of the parents. [4][5][6][7][8] This results from the production of gametes and embryos with unbalanced chromosome sets.9,10 The clinical consequences of such abnormal gametes include sterility, repeated abortions, and giving birth to malformed children. 11,12Several studies have been done in various countries to determine the contribution of chromosome abnormalities in parents with fetal wastage. 13 To our knowledge, no such studies have been done in the Arabian Peninsula. The aim of this study was to assess the frequency and nature of chromosomal aberrations that contribute to the occurrence of repeated abortions in Saudi Arabia. This should assist physicians in Saudi Arabia and other neighboring countries by increasing their awareness of the frequency of cytogenetic abnormalities in cases with repeated abortions. It also provides figures for comparison with other countries and research centers. Materials and MethodsThis study included all Saudi couples with repeated abortions who were referred for cytogenetic studies between December 1994 and December 1998 at King Khalid University Hospital in Riyadh, Saudi Arabia. All cases were ascertained to have had two or more spontaneous abortions. Couples who were referred because of having previous children with congenital anomalies and abortions were not included in the study. The obstetric history of couples was either recorded on the request form or retrieved from the files of patients.For routine cytogenetic analysis, 0.3 mL of peripheral blood was incubated in complete lymphocyte culture medium (10% fetal bovine serum in RPMI 1640, with 0.15% phytohemagglutinin and 1% Penstrept in 5% CO 2 incubator at 37°C for three days). Metaphases were harvested by adding colcemid for 20 minutes, followed by hypotonic KCl treatment for 5 minutes and fixation, using standard 3:1 methanol-acetic fixative (all the reagents were from GIBCO Life Technologies Ltd., Paisley, Scotland). The high-resolution study was done by synchronization, using methotrexate (10 -7 M...

Background Evidence is emerging that inter-daily meal pattern variability potentially impacts on response such as thermic effect of food (TEF), macronutrient metabolism and appetite. Objectives To investigate the effect of irregular meal pattern on TEF, glucose, insulin, lipid profile and appetite regulation in females with overweight or obesity and confirmed insulin resistance. Design In a randomized crossover trial, 9 females [mean±SD BMI: 33.3±3.1 kg/m2) with confirmed insulin resistance consumed a regular (14 days; 6 meals/d) and an irregular (14 days; 3-9 meals/d) meal pattern separated by a 14-d wash-out interval. Identical foods were provided during the interventions and at the start and end of each meal pattern participants attended the laboratory after an overnight fast. Energy expenditure, glucose, insulin, lipids, adiponectin, leptin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and ghrelin were measured at baseline and for three hours after consumption of a test drink, after which an ad libitum test meal was offered. Subjective appetite ratings were recorded before and after the test drink, after the ad libitum meal, and during the intervention. Continuous interstitial glucose monitoring was undertaken for 7 consecutive days during each intervention. Results TEF (over 3 h) was significantly lower post-irregular intervention compared with post-regular (97.7±19.2 kJ*3h in post-regular visit, and 76.7±35.2 kJ*3h in post-irregular visit (Paired T-test, P = 0.048). Differences in HOMA-IR between the two interventions (3.3±1.7 and 3.6±1.6 in post-regular and post-irregular meal pattern, respectively) were not significant. Net iAUC for GLP-1 concentrations (over 3 h) post-regular meal pattern were higher (864.9±456.1 pmol/L*3h) than post-irregular meal pattern (487.6±271.7 pmol/L*3h), (Paired T-test; P = 0.005). Conclusion Following a 14-d period of irregular meal pattern, TEF was significantly less than following regular meal pattern potentially compromising weight management if sustained long term. www.clinicaltrials.gov (ID number; NCT02582606)

The human body requires energy to function. Adenosine triphosphate (ATP) is the cellular currency for energy-requiring processes including mechanical work (i.e., exercise). ATP used by the cells is ultimately derived from the catabolism of energy substrate molecules—carbohydrates, fat, and protein. In prolonged moderate to high-intensity exercise, there is a delicate interplay between carbohydrate and fat metabolism, and this bioenergetic process is tightly regulated by numerous physiological, nutritional, and environmental factors such as exercise intensity and duration, body mass and feeding state. Carbohydrate metabolism is of critical importance during prolonged endurance-type exercise, reflecting the physiological need to regulate glucose homeostasis, assuring optimal glycogen storage, proper muscle fuelling, and delaying the onset of fatigue. Fat metabolism represents a sustainable source of energy to meet energy demands and preserve the ‘limited’ carbohydrate stores. Coordinated neural, hormonal and circulatory events occur during prolonged endurance-type exercise, facilitating the delivery of fatty acids from adipose tissue to the working muscle for oxidation. However, with increasing exercise intensity, fat oxidation declines and is unable to supply ATP at the rate of the exercise demand. Protein is considered a subsidiary source of energy supporting carbohydrates and fat metabolism, contributing to approximately 10% of total ATP turnover during prolonged endurance-type exercise. In this review we present an overview of substrate metabolism during prolonged endurance-type exercise and the regulatory mechanisms involved in ATP turnover to meet the energetic demands of exercise.

Early meal timing and chronotype are associated with lower BMI, but their impact on appetite is poorly understood. We examined the impact of meal timing and chronotype on appetite and food reward. Forty-four adults were divided into early (EC; Morningness–Eveningness Questionnaire (MEQ) score = 55 ± 5) or late chronotype (LC; MEQ score = 40 ± 6) and assessed for body mass index, habitual energy intake (EI; three-day online dietary record) and eating behavior traits from the Three-Factor Eating Questionnaire (TFEQ). Participants attended the laboratory after ≥3 h fast on two occasions for early (AM; 8–10 a.m.) and late (PM; 4–6 p.m.) counterbalanced testing sessions in a 2 × 2 design. Appetite ratings and food reward (validated diurnal Leeds Food Preference Questionnaire) were measured in response to a standardized test meal. LC was associated with higher BMI (p = 0.01), but not with EI or TFEQ. The composite appetite score was lower in AM than PM (MΔ= −5 (95% CI −10, −0.2) mm, p = 0.040). Perceived test meal fillingness was higher in AM than PM and EC compared to LC (p ≤ 0.038). Liking and wanting high-fat food were lower in AM than PM (p ≤ 0.004). The late chronotype was associated with greater desire for high-fat food (p = 0.006). To conclude, early meal timing and early chronotype are independently associated with smaller appetite and lower desire for high-fat food.

The associations between sarcopenia, adiposity indices and metabolic dysregulation still remain controversial. We aimed to assess and compare insulin resistance and metabolic profile in sarcopenic and non-sarcopenic obese Saudi adult men. Methods: This cross sectional study was conducted at the College of Sports Sciences, King Saud University, Riyadh. We recruited 312 Saudi adult male individuals and 288 were finally selected for the study. Body composition analysis and hand grip strength (HGS) were estimated by bioimpedance analysis (BIA) and dynamometer in all subjects, respectively. Fasting blood samples were collected for glucose (FBG), basal insulin (BI) and lipid profile. The subjects were divided into three groups based on the body composition parameters, appendicular lean mass (ALM) and body fat percentage (BF%), into non-obese (NonOb) [Normal ALM+<25 BF%], obese without sarcopenia (ObNonS) [Normal ALM+>25 BF%] and obese with sarcopenia (ObS) [Low ALM+>25 BF%]. Results: Obese subjects had significantly higher BI, HOMA-IR and HOMA-β compared to non-obese. Moreover, comparison between two obese groups revealed that both BI and HOMA-IR levels were higher in ObS subjects compared to ObNonS individuals revealing that sarcopenia exacerbates the insulin resistance profile. There was a significant trend of higher resistance and lower sensitivity from non-obese to obesity with sarcopenia. Total cholesterol (TC) and triglycerides (TG) were significantly higher and high density lipoprotein cholesterol (HDL-C) was significantly lower in sarcopenic obese subjects compared to non-sarcopenic obese individuals. The worsening effects were more significant at cutoff point of 7.46 on insulin indices and lipid profile showing that sarcopenia associated with obesity exacerbates the dyslipidemia. Conclusion: Our study shows that obesity associated with sarcopenia exhibits significantly greater insulin resistance and dyslipidemia than sarcopenia or obesity per se. Therefore, sarcopenic obesity might be an independent risk factor for metabolic disease progression.