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A fall in blood pressure (BP) following a meal is well known and is usually a transient phenomenon, due to appropriate cardiovascular adjustments. Older individuals and those with high BP experience a greater postprandial fall that can manifest as postprandial hypotension (PPH). Fibroblast growth factor 21 (FGF21) is positively associated with BP, and is known to increase after meal ingestion. We explored whether fasting FGF21 or its postprandial change would be associated with meal induced BP change, after accounting for several covariates. Eighty-three Western Australian adults were studied. Supine resting BP was recorded and an oral glucose test was administered. Serial measurements of systolic BP (SBP) and diastolic BP (DBP) were then made in duplicate every 30 min up to 120 min. Fasting and 120 min blood samples were analysed for FGF21 and clinical chemistry. Multiple linear regression analyses of the incremental area under curve of postprandial SBP and DBP was conducted on 12 known determinants. The final parsimonious model based on backward regression of postprandial SBP included fasting SBP, gender, fasting insulin and fasting FGF21 (β = −0.009 (95% confidence interval (CI): 0.017, −0.002, P = 0.015)). For postprandial DBP these included fasting DBP, gender, fasting glucose, fasting insulin and fasting FGF21 (β = −0.005; 95% CI: 0.010, −0.001, P = 0.021). A higher fasting FGF21, independent of glucose and insulin, was associated with a greater postprandial decline in SBP and in DBP. • We studied the association between serum FGF 21 and postprandial decline in blood pressure following a glucose load. • Serum FGF21 increased in response to oral glucose, while both SBP and DBP declined. • Fasting FGF21 but not its postprandial change, was a significant predictor of the drop in SBP and DBP. • Fasting FGF21 may be a useful clinical predictor of postprandial hypotension. [ABSTRACT FROM AUTHOR]

We determined whether individual components of metabolic syndrome (MetS) mediated the direct association of vitamin D status (25OHD) on resting energy expenditure (REE). Multiple linear regression determined predictors of REE from data on 180 men and women from two ethnic groups. We then modelled a mediation pathway through components of MetS on the direct association between 25OHD and REE. The mediation modelling used the PROCESS SPSS Macro (version 4.0) based on 5000 bootstrapped samples, with the adjustment for different sets of covariates. REE was significantly predicted by age, fat mass (FM), fat free mass (FFM), ethnicity, inverse ln insulin, 25OHD, triglycerides (TG), systolic blood pressure (SBP) and, to some extent, by time of REE measurements (p < 0.094). Adjustment for all these covariates, resulted in a negative indirect mediation effect of TG [β coefficient (bootstrapped SE): 0.95 (0.519); bootstrapped 95% CI: 2.172, -0.165; p < 0.05] and a concurrent negative mediation of SBP [β coefficient (bootstrapped SE): 0.72(0.484); bootstrapped 95% CI: 1.851, -0.011; p < 0.05]. There remained a positive direct pathway from 25OHD to REE [β coefficient (S.E): 4.715 (2.129); p = 0.028], however the total effect of 25OHD was dampened [β coefficient (S.E): 3.04 (2.126); p = 0.154]. Independent of insulin sensitivity, a negative mediation by TG and SBP dampened the overall effect of 25OHD on REE. • There is an interplay between vitamin D status, insulin sensitivity, metabolic syndrome and energy metabolism. • Some metabolic syndrome components negatively mediated the link between vitamin D status and resting energy expenditure. • Such pathways would lessen the impact of vitamin D supplementation on human energy expenditure. [ABSTRACT FROM AUTHOR]

The purpose of the study was to evaluate the determinants of cardiorespiratory fitness (CRF) in Iranian adults and the potential contribution of vitamin D status. In this cross-sectional study 264 cases (116 men and 147 women aged 18–70 years old were participated. Maximal oxygen consumption (VO 2 max) was measured by the Bruce protocol utilizing treadmill exercise testing. Anthropometric data, body composition and fasting blood glucose and lipid concentrations were measured. Serum levels of 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH) 2 D) were assessed using enzyme-linked immunosorbent assay. Stepwise linear regression analysis was applied to determine significant predictors of VO2 peak. We tested non-linear (quadratic and cubic terms) versus linear association of adjusted (for determinants) VO2 max and vitamin D levels. Multiple regression results showed that fat free mass, HDL-C and physical activity, waist circumference, age and sex were determinants of VO 2 peak. All of these explained the 65.3% of VO2 peak. There was a non-linear cubic association (R2 = 0.03, p = 0.046) between serum 25(OH)D and adjusted VO2 peak in which 25(OH)D in people with a high 25(OH)D levels (>60 nmol/L), had better fitness and those with serum 25(OH) less than 20 nmol/L. We found no linear and non-linear associations between serum 1,25(OH) 2 D and adjusted VO 2 max. Our results showed that waist circumference and HDL-C, as components of metabolic syndrome, contribute ∼2% to the variance in VO 2 max. Moreover, high concentrations of 25(OH)D but not 1,25(OH) 2 D may make additional contributions to CRF. • Cardiorespiratory fitness may be associated with metabolic syndrome and low levels of serum vitamin D. • Waist circumference and high density lipoprotein cholesterol were determinants of cardiorespiratory fitness. • High concentrations of 25(OH)D may be associated with a better cardiorespiratory fitness. • Nor linear and neither non-linear associations were found between 1,25(OH) 2 D and cardiorespiratory fitness. [ABSTRACT FROM AUTHOR]

Summary: Aim: To determine whether basal metabolic rate (BMR) was causally related to MetS, and to study the role of gender in this relationship. Methods: Seventy-two Caucasian subjects (43 women, 29 men) had changes in basal metabolic rate (BMR), carbohydrate oxidation rate (COR), fat oxidation rate (FOR) and prevalence of the metabolic syndrome (MetS) assessed in response to weight loss. Results: There was a significant gender×MetS interaction in BMR at the start. Women with MetS had higher adjusted BMR, whilst men with MetS had lower adjusted BMR than their respective counterparts. Weight loss resulted in a significant decrease in fat mass (−5.2±0.31kg, p =0.001), fat free mass (−2.3±0.27kg, p =0.001), BMR (−549±58kJ/d, p =0.001) and a decreased proportion of MetS (22/72, χ 2 =0.005). Subjects who recovered from MetS after weight loss (RMS) had ∼250kJ/d significantly lower adjusted BMR compared to those who were never MetS (NMS, p =0.046) and those who still had MetS (MetS+, p =0.047). Regression analysis showed that change (Δ) in BMR was best determined by Δglucose×gender interaction (r 2 =23%), ΔFOR (r 2 =20.3%), ΔCOR (r 2 =19.4%) and Δtriglycerides (r 2 =7.8%). Conclusions: There is a sexual dimorphism of BMR in MetS. Overall, the data support the notion that alterations in BMR may be central to the etiopathogenesis of MetS. [ABSTRACT FROM AUTHOR]

Abstract: Background: Calcium and vitamin D may modulate postprandial endothelial function. Subjects and Methods: Seven lean, young males completed a single blind randomized crossover design where they consumed three breakfast meals containing varying calcium and vitamin D (meal 1 ∼200mg/15IU, meal 2 ∼450mg/140IU, and meal 3 ∼700mg/265IU). Stiffness index (SI), reflective index (RI) and pulse rate (PR) were serially assessed from the digital volume pulse by photoplethysmography (Pulse Trace PT-1000, Micro Medical, UK). Results: Incremental areas under the curve over 3h (Δ) were analyzed by repeated measures ANOVA. ΔPTH was significantly less suppressed with meal A than with meal B and C (P =0.003). In contrast, ΔRI was significantly more suppressed following meal A than with either meal B or C (P =0.021). ΔSI did not change with meal ingestion and there was no difference in the rise of Δglucose, Δinsulin and ΔPR between meals. Conclusion: Higher calcium and vitamin D at breakfast prevented the fall in postprandial vascular tone without changes in glucose or insulin. [ABSTRACT FROM AUTHOR]

Aims To examine the influence of ethnicity and glucose tolerance status on subjective sensations and food intake in overweight/obese Asian and European Australians. Methods 18 Asians and 26 Europids were classified as normal glucose tolerance (NGT) and impaired glucose tolerance (IGT) based on serial measures of finger-prick glucose following an oral glucose tolerance test (OGTT). Subjective sensations of hunger and satiety were measured before and every 15 min after the OGTT using a visual analogue scale (VAS). Food intake was measured covertly from consumption of a buffet style lunch and from self-maintained 24 h food records. All serial measurements were converted into total area under the curve (TAUC) and comparisons adjusted for age, fat and fat-free mass. Results There was a significant difference interaction between ethnicity (ETH) and glucose tolerance (GTT) for subjective fullness, desire for food and prospective food intake. IGT Asians had significantly greater sensations of fullness, but lesser prospective food and desire to eat, as compared to other groups. However there were no differences in calorie and macronutrient intake at buffet lunch or over 24-h. Conclusion Interactions between ethnicity and glucose tolerance status in subjective sensations did not transcribe to differences in prospective food intake. [ABSTRACT FROM AUTHOR]

Summary: Objectives: The purpose of the present study was to evaluate the association between self-perception of body weight, weight loss approaches and measured body mass index (BMI) and waist circumference (WC) among Sri Lankan adults. Methods: A nationally representative sample of 600 adults aged ≥18 years was selected using a multi-stage random cluster sampling technique. An interviewer-administrated questionnaire was used to assess demographic characteristics, body weight perception, abdominal obesity perception and details of weight losing practices. Weight, height and waist circumference (WC) were measured and Asian anthropometric cut-offs for BMI and WC were applied. Results: Body weight mis-perception was common among Sri Lankan adults. Two-thirds of overweight males and 44.7% females considered themselves as ‘about right weight’, moreover, 4.1% and 7.6% overweight men and women reported themselves as being ‘underweight’. Over one third of both male and female obese subjects perceived themselves as ‘about right weight’ or ‘underweight’. Nearly 32% of centrally obese men and women perceived that their WC is about right. People who perceived themselves as overweight or very overweight (n =154) only 63.6% tried to lose weight (n =98), and one quarter of adults sought advice from professionals (n =39). Conclusion: Body weight misperception was common among underweight, healthy weight, overweight, and obese adults in Sri Lanka. Over 2/3 of overweight and 1/3 of obese Sri Lankan adults believe they are in right weight category or are under weight. [Copyright &y& Elsevier]