Branched Chain Amino Acid Supplementation to a Hypocaloric Diet Does Not Affect Resting Metabolic Rate but Increases Postprandial Fat Oxidation Response in Overweight and Obese Adults after Weight Loss Intervention.

BACKGROUND: Branched chain amino acids (BCAA) supplementation is reported to aid in lean mass preservation, which may in turn minimize the reduction in resting metabolic rate (RMR) during weight loss. Our study aimed to examine the effect of BCAA supplementation to a hypocaloric diet on RMR and substrate utilization during a weight loss intervention. METHODS: A total of 111 Chinese subjects comprising 55 males and 56 females aged 21 to 45 years old with BMI between 25 and 36 kg/m2 were randomized into three hypocaloric diet groups: (1) standard-protein (14%) with placebo (CT), (2) standard-protein with BCAA, and (3) high-protein (27%) with placebo. Indirect calorimetry was used to measure RMR, carbohydrate, and fat oxidation before and after 16 weeks of dietary intervention. RESULTS: RMR was reduced from 1600 ± 270 kcal/day to 1500 ± 264 kcal/day (p < 0.0005) after weight loss, but no significant differences in the change of RMR, respiratory quotient, and percentage of fat and carbohydrate oxidation were observed among the three diet groups. Subjects with BCAA supplementation had an increased postprandial fat (p = 0.021) and decreased postprandial carbohydrate (p = 0.044) oxidation responses compared to the CT group after dietary intervention. CONCLUSIONS: BCAA-supplemented standard-protein diet did not significantly attenuate reduction of RMR compared to standard-protein and high-protein diets. However, the postprandial fat oxidation response increased after BCAA-supplemented weight loss intervention.

Branched-Chain Amino Acid Supplementation Does Not Preserve Lean Mass or Affect Metabolic Profile in Adults with Overweight or Obesity in a Randomized Controlled Weight Loss Intervention.

BACKGROUND: Branched-chain amino acid (BCAA) supplementation has been shown to increase muscle mass or prevent muscle loss during weight loss. OBJECTIVE: We aimed to investigate the effects of a BCAA-supplemented hypocaloric diet on lean mass preservation and insulin sensitivity. METHODS: A total of 132 Chinese adults (63 men and 69 women aged 21-45 y, BMI 25-36 kg/m2) were block randomly assigned by gender and BMI into 3 hypocaloric diet (deficit of 500 kcal/d) groups: standard-protein (14%) with placebo (control, CT) or BCAA supplements at 0.1 g · kg-1 body weight · d-1 (BCAA) or high-protein (27%) with placebo (HP). The subjects underwent 16 wk of dietary intervention with provision of meals and supplements, followed by 8 wk of weight maintenance with provision of supplements only. One-way ANOVA analysis was conducted to analyze the primary (lean mass and insulin sensitivity) and secondary outcomes (anthropometric and metabolic parameters) among the 3 groups. Paired t-test was used to analyze the change in each group. RESULTS: The 3 groups demonstrated similar significant reductions in body weight (7.97%), fat mass (13.8%), and waist circumference (7.27%) after 16 wk of energy deficit. Lean mass loss in BCAA (4.39%) tended to be lower than in CT (5.39%) and higher compared with HP (3.67%) (P = 0.06). Calf muscle volume increased 3.4% in BCAA and intramyocellular lipids (IMCLs) decreased in BCAA (17%) and HP (18%) (P < 0.05) over 16 wk. During the 8 wk weight maintenance period, lean mass gain in BCAA (1.03%) tended to be lower compared with CT (1.58%) and higher than in HP (-0.002%) (P = 0.04). Lean mass gain differed significantly between CT and HP (P = 0.03). Insulin sensitivity and metabolic profiles did not differ among the groups throughout the study period. CONCLUSIONS: BCAA supplementation does not preserve lean mass or affect insulin sensitivity in overweight and obese adults during weight loss. A higher protein diet may be more advantageous for lean mass preservation.

High placental inositol content associated with suppressed pro-adipogenic effects of maternal glycaemia in offspring: the GUSTO cohort.

BACKGROUND/OBJECTIVES: Maternal glycaemia promotes fetal adiposity. Inositol, an insulin sensitizer, has been trialled for gestational diabetes prevention. The placenta has been implicated in how maternal hyperglycaemia generates fetal pathophysiology, but no studies have examined whether placental inositol biology is altered with maternal hyperglycaemia, nor whether such alterations impact fetal physiology. We aimed to investigate whether the effects of maternal glycaemia on offspring birthweight and adiposity at birth differed across placental inositol levels. METHODS: Using longitudinal data from the Growing Up in Singapore Towards healthy Outcomes cohort, maternal fasting glucose (FPG) and 2-hour plasma glucose (2hPG) were obtained in pregnant women by a 75-g oral glucose tolerance test around 26 weeks' gestation. Relative placental inositol was quantified by liquid chromatography-mass spectrometry. Primary outcomes were birthweight (n = 884) and abdominal adipose tissue (AAT) volumes measured by neonatal MRI scanning in a subset (n = 262) of term singleton pregnancies. Multiple linear regression analyses were performed. RESULTS: Placental inositol was lower in those with higher 2hPG, no exposure to tobacco smoke antenatally, with vaginal delivery and shorter gestation. Positive associations of FPG with birthweight (adjusted ß [95% CI] 164.8 g [109.1, 220.5]) and AAT (17.3 ml [11.9, 22.6] per mmol glucose) were observed, with significant interactions between inositol tertiles and FPG in relation to these outcomes (p < 0.05). Stratification by inositol tertiles showed that each mmol/L increase in FPG was associated with increased birthweight and AAT volume among cases within the lowest (birthweight = 174.2 g [81.2, 267.2], AAT = 21.0 ml [13.1, 28.8]) and middle inositol tertiles (birthweight = 202.0 g [103.8, 300.1], AAT = 19.7 ml [9.7, 29.7]). However, no significant association was found among cases within the highest tertile (birthweight = 81.0 g [-21.2, 183.2], AAT = 0.8 ml [-8.4, 10.0]). CONCLUSIONS: High placental inositol may protect the fetus from the pro-adipogenic effects of maternal glycaemia. Studies are warranted to investigate whether prenatal inositol supplementation can increase placental inositol and reduce fetal adiposity.

Long-chain polyunsaturated fatty acids, gestation duration, and birth size: a Mendelian randomization study using fatty acid desaturase variants.

Background: In randomized trials, supplementation of n-3 (ω-3) long-chain polyunsaturated fatty acids (LC-PUFAs) during pregnancy has resulted in increased size at birth, which is attributable to longer gestation. Objective: We examined this finding by using a Mendelian randomization approach utilizing fatty acid desaturase (FADS) gene variants affecting LC-PUFA metabolism. Design: As part of a tri-ethnic mother-offspring cohort in Singapore, 35 genetic variants in FADS1, FADS2, and FADS3 were genotyped in 898 mothers and 1103 offspring. Maternal plasma n-3 and n-6 PUFA concentrations at 26-28 wk of gestation were measured. Gestation duration was derived from an ultrasound dating scan in early pregnancy and from birth date. Birth length and weight were measured. Eight FADS variants were selected through a tagging-SNP approach and examined in association with PUFA concentrations, gestation duration among spontaneous labors, and birth size with the use of ethnicity-adjusted linear regressions and survival models that accounted for the competing risks of induced labor and prelabor cesarean delivery. Results: Maternal FADS1 variant rs174546, tagging for 8 other variants located on FADS1 and FADS2, was strongly related to plasma n-6 but not n-3 LC-PUFA concentrations. Offspring and maternal FADS3 variants were associated with gestation duration among women who had spontaneous labor: each copy of rs174450 minor allele C was associated with a shorter gestation by 2.2 d (95% CI: 0.9, 3.4 d) and 1.9 d (0.7, 3.0 d) for maternal and offspring variants, respectively. In survival models, rs174450 minor allele homozygotes had reduced time to delivery after spontaneous labor compared with major allele homozygotes [HR (95% CI): 1.51 (1.18, 1.95) and 1.51 (1.20, 1.89) for mothers and offspring, respectively]. Conclusions: With the use of a Mendelian randomization approach, we observed associations between FADS variants and gestation duration. This suggests a potential role of LC-PUFAs in gestation duration. This trial was registered at http://www.clinicaltrials.gov as NCT01174875.

High folate and low vitamin B12 status during pregnancy is associated with gestational diabetes mellitus.

BACKGROUND & AIMS: B-vitamins and homocysteine may contribute to the development of gestational diabetes mellitus (GDM), but existing studies are inconsistent. We examined the cross-sectional associations of plasma folate, vitamins B6, B12, and homocysteine concentrations with GDM and glycemia in a sample of multi-ethnic Asian pregnant women. METHODS: Plasma concentrations of folate, vitamins B6, B12, homocysteine and glucose were measured at 26-weeks' gestation in 913 pregnant women. GDM was diagnosed using the 1999 World Health Organization criteria. Associations were examined with linear or logistic regression, adjusted for confounders and stratified by ethnicity. RESULTS: Higher plasma folate was associated with higher 2-h glucose and higher odds of GDM [0.15 (0.02, 0.23) per 1-SD increment in folate, OR 1.29 (1.00, 1.60)], mainly among Indian mothers. Higher plasma vitamin B12 and homocysteine were associated with lower fasting and 2-h glucose, and lower odds of GDM [-0.04 (-0.07, -0.01) per 1-SD increment in B12 and -0.09 (-0.18, -0.003) respectively, OR: 0.81 (0.68, 0.97); -0.05 (-0.08, -0.02) per 1-SD increment in homocysteine and -0.12 (-0.21, -0.02) respectively, OR: 0.76 (0.62, 0.92)]. The highest odds of GDM were observed among women with combined vitamin B12 insufficiency and high folate concentration [OR: 1.97 (1.05, 3.68)]. An association between higher vitamin B6 and higher 2-h glucose shifted towards null adjusting for other B-vitamins. CONCLUSIONS: Higher maternal folate coupled with vitamin B12 insufficiency was associated with higher GDM risk. This finding has potential implications for antenatal supplement recommendations but will require confirmation in future studies.

Prospective associations of maternal betaine status with offspring weight and body composition at birth: the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort study.

BACKGROUND: Betaine supplementation results in lower body weight and fat mass and higher lean mass in animals and adult humans. However, the relation between maternal betaine status and offspring birth weight and body composition is less known. OBJECTIVE: The aim was to examine the association between maternal betaine status and neonatal birth size and adiposity in an Asian mother-offspring cohort. DESIGN: We included 955 pregnant women whose plasma betaine concentrations were measured at 26-28 wk of gestation. Neonatal anthropometric values were measured at birth, and abdominal adipose tissue compartments were assessed by MRI in a subset of infants (n = 307) in the first 14 d after birth. Multivariate general linear models were used to adjust for gestational age; fetal sex; and maternal age, height, education, ethnicity, prepregnancy body mass index, and plasma folate, vitamin B-12, and choline concentrations. RESULTS: The mean ± SD plasma concentration of betaine was 13.2 ± 2.7 µmol/L (range: 5.3-25.0 µmol/L). After adjustment for covariates, higher maternal plasma betaine was associated with lower birth weight (ß: -57.6 g; 95% CI: -109.9, -5.3 g), shorter birth length (ß: -0.29 cm per 5-µmol/L increment; 95% CI: -0.55, -0.03 cm), smaller head circumference (-0.20 cm; 95% CI: -0.38, -0.02 cm), smaller midupper arm circumference (-0.16 cm; 95% CI: -0.30, -0.03 cm), lower volumes of abdominal superficial subcutaneous adipose tissue (-4.53 mL; 95% CI: -8.70, -0.36 mL), and a higher risk of small-for-gestational-age birth (OR: 1.57; 95% CI: 1.05, 2.35). CONCLUSIONS: Higher maternal betaine status was generally associated with smaller infant birth size and less abdominal fat mass. Further studies are needed to replicate these findings and to understand their biological mechanisms. This study was registered at clinicaltrials.gov as NCT01174875.

Demographic Characteristics, Health Behaviors Before and During Pregnancy, and Pregnancy and Birth Outcomes in Mothers with Different Pregnancy Planning Status.

Studies on pregnancy intentions and their consequences have yielded mixed results. Here, we comprehensively analyzed the maternal characteristics, health behaviors before and during pregnancy, as well as pregnancy and birth outcomes, across three different pregnancy planning status in 861 women participating in an ongoing Asian mother-offspring cohort study. At 26-28 weeks' gestation, the women's intention and enthusiasm toward their pregnancy were used to classify their pregnancy into planned or unplanned, and unplanned pregnancy was further subdivided into mistimed or unintended. Data on maternal characteristics, health behaviors, and pregnancy outcomes up to that stage were recorded. After delivery, birth outcomes of the offspring were recorded. Linear and logistic regression analyses were performed. Overall, 56 % had a planned pregnancy, 39 % mistimed, and 5 % unintended. Compared to women who planned their pregnancy, women with mistimed pregnancy had higher body mass index and were more likely to have cigarette smoke exposure and less likely to have folic acid supplementation. At 26-28 weeks' gestation, unintended pregnancy was associated with increased anxiety. Neonates of mistimed pregnancy had shorter birth length compared to those of planned pregnancy, even after adjustment for maternal baseline demographics. These findings suggest that mothers who did not plan their pregnancy had less desirable characteristics or health behaviors before and during pregnancy and poorer pregnancy and birth outcomes. Shorter birth length in mistimed pregnancy may be attributed to maternal behaviors before or in the early stages of pregnancy, therefore highlighting the importance of preconception health promotion and screening for women of child-bearing age.

Infant Feeding Practices in a Multi-Ethnic Asian Cohort: The GUSTO Study.

The optimal introduction of complementary foods provides infants with nutritionally balanced diets and establishes healthy eating habits. The documentation of infant feeding practices in multi-ethnic Asian populations is limited. In a Singapore cohort study (GUSTO), 842 mother-infant dyads were interviewed regarding their feeding practices when the infants were aged 9 and 12 months. In the first year, 20.5% of infants were given dietary supplements, while 5.7% took probiotics and 15.7% homeopathic preparations. At age 9 months, 45.8% of infants had seasonings added to their foods, increasing to 56.3% at 12 months. At age 12 months, 32.7% of infants were given blended food, although 92.3% had begun some form of self-feeding. Additionally, 87.4% of infants were fed milk via a bottle, while a third of them had food items added into their bottles. At both time points, more than a third of infants were provided sweetened drinks via the bottle. Infants of Indian ethnicity were more likely to be given dietary supplements, have oil and seasonings added to their foods and consumed sweetened drinks from the bottle (p < 0.001). These findings provide a better understanding of variations in infant feeding practices, so that healthcare professionals can offer more targeted and culturally-appropriate advice.

Detection through screening of maternal thyrotoxicosis induced central hypothyroidism in newborns.

Use of a third generation TSH assay enabled extremely low values of TSH to be detected through newborn screening. The use of a supplemental free thyroxine improved testing specificity. The hypothyroidism observed is believed to be secondary to suppression of the hypothalamic-pituitary-thyroid axis by placentally transferred maternal thyroxine.