Association of late-night carbohydrate intake with glucose tolerance among pregnant African American women

Association between sleep duration and quality with food intake, chrononutrition patterns, and weight gain during pregnancy

To analyse the association between sleep duration and quality with food intake, chrononutrition patterns, and weight gain during pregnancy. A prospective cohort study was conducted with 100 pregnant women. Data collection occurred once during each gestational trimester. The assessment of sleep quality and duration was performed using the Pittsburgh Sleep Quality Index. Food intake was assessed using three 24-h recalls in each trimester. Body weight was measured during the three trimesters, and height was measured only once to calculate the BMI. Linear regression analyses were performed to associate sleep duration and quality with food consumption and weight gain variables. Longer sleep duration was associated with a later dinner in the first trimester (β = 0·228, P = 0·025) and earlier in the third trimester (β = -0·223, P = 0·026), in addition to a later morning snack in the second trimester (β = 0·315, P = 0·026). Worse sleep quality was associated with higher total energy intake (β = 0·243, P = 0·044), total fat (β = 0·291, P = 0·015) and the chrononutrition variables such as a higher number of meals (β = 0·252, P = 0·037), higher energetic midpoint (β = 0·243, P = 0·044) and shorter fasting time (β = -0·255, P = 0·034) in the third trimester. Sleep quality was also associated with a higher BMI in the first trimester of pregnancy (β = 0·420, P = < 0·001). Most of the associations found in the present study show that poor sleep is associated with higher energy and fat intake and higher BMI. Longer sleep duration was associated with a later dinner in early pregnancy and an earlier dinner in late pregnancy, as well as with a later morning snack in the second trimester of pregnancy.

Associations of predominant night-eating with plasma glycemic status and continuous glucose monitoring measures among pregnant women

BACKGROUND & AIMS

To examine whether predominant night-eating, defined as more than 50% of total daily energy intake consumed between 1900 and 0659 h, is associated with glycemic outcomes in pregnancy.

METHODS

This was a prospective cohort study of 277 healthy pregnant women with complete 4-day dietary intake records at 18-24 weeks gestation, recruited from KK Women's and Children's Hospital, Singapore. Primary outcomes were fasting, 1-h, and 2-h plasma glucose after a 75-g oral glucose tolerance test at 24-28 weeks gestation. Secondary outcomes were gestational diabetes mellitus (GDM), fasting insulin, homeostasis model assessment of insulin resistance (HOMA2-IR), β-cell function (HOMA2-%B), and continuous glucose monitoring (CGM) measures. Glucose variables in continuous form were loge-transformed before analyses.

RESULTS

Predominant night-eating (11.6%) was associated with higher fasting glucose (geometric mean ratio (95% confidence interval) 1.05 (1.01, 1.08)) and 1-h glucose (1.11 (1.01, 1.21)), but not with 2-h glucose or GDM risk. Predominant night-eating women had lower fasting insulin (0.77 (0.63, 0.95)), lower HOMA2-IR (0.78 (0.64, 0.97)), and lower HOMA2-%B (0.77 (0.67, 0.89)) than their predominant day-eating counterparts. For CGM measures, predominant night-eating was associated with higher mean glucose (1.07 (1.00, 1.15)), higher glucose management indicator (1.05 (1.00, 1.10)), and higher overall glucose levels throughout 24 h (1.10 (1.02, 1.19)). All these associations were adjusted for socio-demographic, lifestyle factors, and diet composition.

CONCLUSION

Predominant night-eating was mainly associated with less desirable glycemic outcomes during pregnancy. Future studies should explore dietary interventions aimed at reducing consumption of relatively more calories at night than day during pregnancy.

Maternal melatonin levels and temporal dietary intake: results from MY-CARE cohort study

Chrononutrition emerges as a novel approach to promote circadian alignment and metabolic health by means of time-of-the-day dietary intake. However, the relationship between maternal circadian rhythm and temporal dietary intake during pregnancy remains understudied. This study aimed to determine the change in melatonin levels in pregnant women across gestation and its association with temporal energy and macronutrient intake. This was a prospective cohort involving 70 healthy primigravidas. During the second and third trimesters, pregnant women provided salivary samples collected at 9:00, 15:00, 21:00, and 3:00 h over a 24 h day for melatonin assay. Data on chrononutrition characteristics were collected using a 3-day food record. Parameters derived from melatonin measurements including mean, amplitude, maximal level, area under the curve with respect to increase (AUC_I), and area under the curve with respect to ground (AUC_G) were computed. A rhythmic melatonin secretion over the day that remained stable across trimesters was observed among the pregnant women. There was no significant elevation in salivary melatonin levels as pregnancy advanced. In the second trimester, higher energy intake during 12:00-15:59 h and 19:00-06:59 h predicted a steeper melatonin AUC_I (β=-0.32, p = 0.034) and higher AUC_G (β = 0.26, p = 0.042), respectively. Macronutrient intake within 12:00-15:59 h was negatively associated with mean melatonin (Fat: β=-0.28, p = 0.041) and AUC_G (Carbohydrate: β=-0.37, p = 0.003; Protein: β=-0.27, p = 0.036; Fat: β=-0.32, p = 0.014). As pregnant women progressed from the second to the third trimester, a flatter AUC_I was associated with a reduced carbohydrate intake during 12:00-15:59 h (β=-0.40, p = 0.026). No significant association was detected during the third trimester. Our findings show that higher energy and macronutrient intakes particularly during 12:00-15:59 h and 19:00-06:59 h are associated with the disparities in maternal melatonin levels. Findings suggest the potential of time-based dietary approaches to entrain circadian rhythm in pregnant women.

Infant temperament is associated with maternal feeding behaviors in early infancy

Parental feeding practices shape infant eating behaviors and may impact obesity risk. For example, feeding on a schedule and using food to soothe have been associated with greater infant weight gain and future obesity risk. Most studies focus on parental determinants of feeding practices, but infant temperament might influence feeding practices parents select. Studies examining associations of infant temperament with parental feeding practices in early infancy are needed. Thus, the purpose of this cross-sectional, observational study was to test the hypothesis that infant temperament would be associated with use of food to soothe and feeding on a schedule. Mother-infant dyads (N = 98) from 3 parent birth cohort studies presented for clinic visits at infant age of 3-5 months. Mothers completed a demographic questionnaire. Feeding practices (use of food to soothe and feeding on a schedule) and maternal perceptions of 3 dimensions of infant temperament (surgency, orienting/regulating, and negative affect) were collected by survey. Spearman partial correlations were used to examine if any of the 3 infant temperament dimensions were associated with use of food to soothe or feeding on a schedule, adjusting for maternal marital status, race/ethnicity, BMI, infant age at the visit, and infant weight-for-length z-score. Greater perceived infant surgency/extraversion was associated with greater use of food to calm (Spearman partial r = 0.25, p < 0.05), but not feeding on a schedule (Spearman partial r = -0.11, p = 0.31). Greater perceived infant negative affect was associated with greater use of food to calm (Spearman partial r = 0.21, p < 0.05). Perceived infant orienting/regulating was not associated with either of the feeding practices examined. These results provide evidence that as early as 3-5 months of age, perceived infant temperament is associated with maternal feeding practices which influence infant growth outcomes.

Assessment of Eating Behaviors and Perceptions of Time-Restricted Eating During Pregnancy

BACKGROUND

The maternal metabolic milieu is challenged during pregnancy and may result in unwarranted metabolic complications. A time-restricted eating (TRE) pattern may optimize the metabolic response to pregnancy by improving glucose metabolism and reducing circulating glucose concentrations, as it does in nonpregnant individuals.

OBJECTIVES

The objectives of this study were to 1) assess eating timing in pregnant women; 2) understand the perceptions of adopting a TRE pattern; 3) determine the barriers and support mechanisms for incorporating a TRE pattern; and 4) identify those most willing to adopt a TRE pattern during pregnancy.

METHODS

This was a cross-sectional quantitative and quasi-qualitative online survey study for women who were pregnant at the time of study completion or had given birth in the prior 2 years. Group analyses were performed based off willingness to try a TRE pattern using chi-squared analyses, independent samples t-tests, or an analysis of variance. Three separate reviewers reviewed qualitative responses.

RESULTS

A total of 431 women (BMI, 27.5 ± 0.3 kg/m2) completed the study. Of the participating women, 23.7% reported willingness to try a TRE pattern during pregnancy. Top barriers to adopting a TRE pattern during pregnancy were concerns for 1) safety; 2) nausea; and 3) hunger. The highest ranked support mechanisms were: 1) the ability to choose the eating window; 2) more frequent prenatal visits to ensure the health of the baby; and 3) receiving feedback from a dietician/nutritionist. Women who did not identify as White/Caucasian expressed a higher willingness to try a TRE pattern during pregnancy (P = 0.01). Women who were nulliparous expressed a higher willingness to try a TRE pattern (P = 0.05).

DISCUSSION

TRE, an alternative dietary strategy shown to optimize metabolic control, may be effective to prevent and manage pregnancy-related metabolic impairments. To create an effective TRE intervention during pregnancy, the input of pregnant mothers is necessary to increase adherence and acceptability.

Is chronotype associated with dietary intake and weight gain during pregnancy? A prospective and longitudinal study

OBJECTIVES

The effects of chronotype on dietary intake and weight gain during pregnancy have not been addressed in the literature. The aim of this study was to analyze the effect of chronotype on eating patterns, energy, and macronutrient intake and distribution, as well as weight gain during pregnancy.

METHODS

This was a prospective cohort study carried out with 100 pregnant women in the first, second, and third gestational trimesters. Dietary intake was assessed by three 24-h dietary recalls in each trimester, totaling nine recalls. Energy and macronutrient intake and distribution were evaluated at meals throughout the day. Chronotype was derived from midsleep time on free days, and the scores obtained were categorized into tertiles. Recommendations from the Institute of Medicine were used to assess the adequacy of weight gain. Generalized estimating equation models were used to determine the effects of chronotype and gestational trimester on eating patterns, daily energy, macronutrient distribution, and weight gain.

RESULTS

Pregnant women with values for midsleep time on free days indicative of eveningness have breakfast later and also have higher energy and carbohydrate intake at dinner than "morning" women. Pregnant "morning" women showed better diet quality in terms of milk and dairy and saturated fat. Also, despite the tendency for all tertiles to gain excess weight during pregnancy, we found that pregnant women with a tendency to eveningness had worse adequacy of gestational weight gain in the third trimester than "morning" women (2.24 ± 0.25 versus 1.22 ± 0.14, P < 0.001).

CONCLUSION

Pregnant women with a tendency to eveningness consume breakfast later in the day and exhibit greater consumption of energy and carbohydrates in the evening, as well as a worse standard of gestational weight gain in the third trimester. Our results emphasize the importance of considering chrononutrition variables in prenatal nutritional guidelines to promote maternal and fetal health.

Meal Timing and Glycemic Control during Pregnancy-Is There a Link?

Hyperglycemia during pregnancy and gestational diabetes mellitus (GDM) constitute an important public health problem due to their prevalence and long-term health consequences both for the mother and offspring. Results from studies in rodents and some clinical investigations suggest that meal time manipulation may be a potential lifestyle approach against conditions involving perturbations in glucose homeostasis (e.g., hyperglycemia, insulin resistance, diabetes, etc.). The purpose of this review is to summarize and critically evaluate the current literature on the role of meal timing and daily nutrient distribution on glycemic control during pregnancy. Only a small number of mostly observational studies have assessed the role of meal timing in glucose homeostasis during pregnancy. Food consumption earlier in the day and short-term fasting with adequate nutrient intake may improve glycemic control during the second and third trimester of gestation. Considering that the field of chrononutrition is still in its infancy and many questions remain unanswered, future prospective and carefully designed studies are needed to better understand the role of meal timing in metabolic homeostasis and maternal and fetal health outcomes during pregnancy.

Chrononutrition during Pregnancy: A Review on Maternal Night-Time Eating

Evidence from women working night shifts during pregnancy indicates that circadian rhythm disruption has the potential to adversely influence pregnancy outcomes. In the general population, chronodisruption with the potential to affect pregnancy outcomes may also be seen in those with high energy intakes in the evening or at night. However, maternal night eating during pregnancy remains understudied. This narrative review provides an overview of the prevalence, contributing factors, nutritional aspects and health implications of night eating during pregnancy. We derived evidence based on cross-sectional studies and longitudinal cohorts. Overall, night eating is common during pregnancy, with the estimated prevalence in different populations ranging from 15% to 45%. The modern lifestyle and the presence of pregnancy symptoms contribute to night eating during pregnancy, which is likely to coexist and may interact with multiple undesirable lifestyle behaviors. Unfavorable nutritional characteristics associated with night eating have the potential to induce aberrant circadian rhythms in pregnant women, resulting in adverse metabolic and pregnancy outcomes. More research, particularly intervention studies, are needed to provide more definite information on the implications of night eating for mother-offspring health.

Higher energy intake at night effects daily energy distribution and contributes to excessive weight gain during pregnancy

OBJECTIVE

The aim of this study was to analyze the effect of nighttime energy intake on daily energy and macronutrient distribution and weight gain during pregnancy.

METHODS

This was a prospective cohort study carried out with 100 pregnant women and the data collection occurred once per trimester. A dietary intake was assessed by three 24-h dietary recalls in each trimester, totaling nine dietary recalls. The distribution of energy and macronutrient intake was evaluated at meals throughout the day in each trimester and overall pregnancy. Women were classified as having "lower" or "higher" nighttime intake (1900 to 0559) if consumption in this period were below or above the median of the population, respectively, for at least two trimesters. Recommendations from the Institute of Medicine were used to assess the adequacy of weight gain. Generalized estimating equation models were used to determine the effects of nighttime intake and gestational trimesters on daily energy distribution and weight gain.

RESULTS

In overall pregnancy, the higher group consumed a higher percentage of energy and macronutrients in the evening meals, and less energy, proteins, and lipids in morning meals when compared with the lower group. Also, women in the higher group had greater excessive weight gain in the third trimester compared with the lower group.

CONCLUSION

Pregnant women with a higher energy intake at night had a lower percentage of energy, protein, and lipid intake in morning meals and a higher percentage of energy and macronutrient intake in the evening meals during pregnancy. A worse standard of gestational weight gain in the third trimester was also observed in pregnant women with a higher energy intake at night.

Effects of timing of food intake on eating patterns, diet quality and weight gain during pregnancy

Studies have suggested that meal timing plays a role in nutritional health, but this subject has not been sufficiently studied in pregnant women. We analysed the effect that timing of food intake has on eating patterns, diet quality and weight gain in a prospective cohort study with 100 pregnant women. Data were collected once per trimester: 4th-12th, 20th-26th and 30th-37th weeks. Food intake was evaluated using three 24-h dietary recalls, which were used to assess eating patterns and diet quality. Distribution of energy and macronutrient intake throughout the day was considered eating patterns. Diet quality was assessed using the Brazilian Healthy Eating Index-Revised. Weight gain was evaluated during each trimester. Women were classified as early or late timing of the first and last eating episodes if these values were below or above the median of the population, respectively (first eating episode = 08.38 hours; last eating episode = 20.20 hours). Generalised estimating equation models adjusted for confounders were used to determine the effects of timing of the first and last eating episodes (groups) and gestational trimesters (time) (independent variable) on eating patterns, diet quality and weight gain (dependent variables). Early eaters of the first eating episode have a higher percentage of energy and carbohydrate intake in morning and a lower at evening meals. They also have a better diet quality for fruit components when compared with late eaters of the first eating episode. Our results emphasise the importance of considering meal timing in the nutritional antenatal guidelines to promote maternal-fetal health.

Maternal night-eating pattern and glucose tolerance during pregnancy: study protocol for a longitudinal study

INTRODUCTION

Coordinating eating schedules with day-night cycles has been shown to improve glucose regulation in adults, but its association with gestational glycaemia is less clear. A better understanding on how eating time can influence glucose levels in pregnancy may improve strategies for gestational glycaemic control. This study aims to examine the association of maternal night-eating pattern with glucose tolerance in the second trimester of pregnancy, and to investigate how lifestyle factors may be related to night-eating pattern.

METHODS AND ANALYSIS

This is an observational longitudinal study that targets to recruit 200 pregnant women at 18-24 weeks' gestation from the KK Women's and Children's Hospital in Singapore. Data collection includes sociodemographics, lifestyle habits and obstetric information. Maternal dietary intake is collected using the 4-day food diary and food frequency questionnaire; while 24-hour physical activity, sedentary behaviour, sleep and light exposure are captured using the accelerometer at 18-24 weeks' gestation. Continuous glucose monitoring at 18-24 weeks' gestation, oral glucose tolerance test and insulin test at 24-28 weeks' gestation are performed to assess glycaemic outcomes. Multivariable generalised linear models will be used to analyse the association of maternal night-eating pattern (consumption of meal and snack during 1900-0659 hours) with glycaemic measures, and the associated factors of night-eating pattern, controlling for potential confounders. Recruitment began in March 2019 and is estimated to end in November 2020.

ETHICS AND DISSEMINATION

Ethical approval has been granted by the Centralised Institutional Review Board of SingHealth, Singapore (reference 2018/2529). The results will be presented at conferences and disseminated in journal articles.

TRIAL REGISTRATION NUMBER

NCT03803345.

Maternal night-time eating and sleep duration in relation to length of gestation and preterm birth

BACKGROUND & AIMS

Maternal metabolic disturbance arising from inappropriate meal timing or sleep deprivation may disrupt circadian rhythm, potentially inducing pregnancy complications. We examined the associations of maternal night-time eating and sleep duration during pregnancy with gestation length and preterm birth.

METHODS

We studied 673 pregnant women from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) cohort. Maternal energy intake by time of day and nightly sleep duration were assessed at 26-28 weeks' gestation. Based on 24-h dietary recall, night-eating was defined as consuming >50% of total energy intake from 1900 to 0659 h. Short sleep duration was defined as <6 h night sleep. Night-eating and short sleep were simultaneously analyzed to examine for associations with a) gestation length using multiple linear regression, and b) preterm birth (<37 weeks' gestation) using logistic regression.

RESULTS

Overall, 15.6% women engaged in night-eating, 12.3% had short sleep and 6.8% delivered preterm. Adjusting for confounding factors, night-eating was associated with 0.45 weeks shortening of gestation length (95% CI -0.75, -0.16) and 2.19-fold higher odds of delivering preterm (1.01, 4.72). Short sleep was associated with 0.33 weeks shortening of gestation length (-0.66, -0.01), but its association with preterm birth did not reach statistical significance (1.81; 0.76, 4.30).

CONCLUSIONS

During pregnancy, women with higher energy consumption at night than during the day had shorter gestation and greater likelihood of delivering preterm. Misalignment of eating time with day-night cycles may be a contributing factor to preterm birth. This points to a potential target for intervention to reduce the risk of preterm birth. Observations for nightly sleep deprivation in relation to gestation length and PTB warrant further confirmation.

Effect of Rice Processing towards Lower Rapidly Available Glucose (RAG) Favors Idli, a South Indian Fermented Food Suitable for Diabetic Patients

The Asian food pattern primarily embraces rice and rice-based products, which mainly comprise 90% starch. Among these various food products, Idli is mostly prepared through fermentation. It has high palatability, and the rapid and highly digestible nature of the food product results in a higher post-glucose level in diabetic patients. A heat-treated Idli rice sample was prepared by roasting parboiled rice at the temperature range of 155 to 165 °C for 65 to 75 s. Idli/rice-based Dokala made from heat-treated rice is better when compared to untreated rice in terms of its microbiological profile and physiochemical properties. The proximate composition of heat-treated parboiled rice Idli/Rice Dokala showed slightly higher values than the untreated parboiled rice Idli/Rice Dokala, which reveals that it has marginally higher nutritive value. Determination of the Rapidly Available Glucose (RAG) and Slowly Available Glucose (SAG) values, SEM analysis, resistant starch analysis, microbial assay, and in vivo studies were performed to determine the glycemic index (GI) and glycemic load in normal and diabetic persons. Sensory analysis also proved that heat-treated Idli/Rice Dokala is superior to untreated based on the color, flavor, appearance, taste, and texture.

Reasons for Late-Night Eating and Willingness to Change:A Qualitative Study in Pregnant Black Women

OBJECTIVE

Late-night eating during pregnancy is associated with greater risk for gestational diabetes. The purposes of this study were to describe reasons why women engage in late-night eating and to understand perceptions about changing this behavior.

DESIGN

Focus groups using a semi-structured interview script.

SETTING

Urban university-affiliated obstetric clinic.

PARTICIPANTS

Low-income black women (n = 18) with overweight/obesity at entry to prenatal care.

PHENOMENON OF INTEREST

Late-night eating.

ANALYSIS

Exhaustive approach coding responses to specific questions.

RESULTS

Individual and interpersonal contributors to late-night eating included hunger, altered sleep patterns, fetal movement, and the influence of others. Food choices were largely driven by taste and convenience. Some women reported that they could alter nightly eating patterns, whereas others would consider changing only if late-night eating were associated with a severe illness or disability for the child.

CONCLUSIONS AND IMPLICATIONS

There was considerable heterogeneity among the participants of this study regarding reasons for late-night eating during pregnancy and attitudes toward changing this behavior. Although the themes identified from this study cannot be generalized, they may be useful to inform future studies. Future research might develop strategies to overcome individual and social factors that contribute to late-night eating during pregnancy.

Association of early pregnancy body mass index with post-partum weight change among African-American women

Post-partum weight retention is relatively common and increases the risk for future obesity. Women who are overweight or obese prior to pregnancy, or who gain excessively during pregnancy, are more likely to retain weight post-partum. Much of the existing research is limited by a single post-partum body-weight measure and therefore cannot distinguish post-partum weight retention from post-partum weight accrual. This study tested the hypothesis that early pregnancy body mass index (BMI) is positively associated with post-partum weight change, independent of gestational weight gain (GWG) and breastfeeding (BF) among African-American women, a demographic group with greater risk for obesity. Healthy African-American women (n = 32) were weighed at 2 weeks and 3 months post-partum to derive post-partum weight change. Data from prenatal care records were retrieved to calculate BMI at the first prenatal care visit and GWG. BF status at 2 weeks post-partum was self-reported. Early pregnancy BMI was positively associated with post-partum weight change (partial r = 0.53, P < 0.005), independent of GWG and BF status at 2 weeks post-partum. These results extend the literature by suggesting that the association between early pregnancy BMI and post-partum weight retention may be at least partially attributable to the accrual of new weight during the post-partum period. Future research in a larger and more diverse cohort is warranted and should explore potential mechanisms contributing to post-partum weight change.

Plasma Vitamin D Deficiency Is Associated With Poor Sleep Quality and Night-Time Eating at Mid-Pregnancy in Singapore

Plasma 25-hydroxyvitamin D (25OHD) deficiency, poor sleep quality, and night-time eating, have been independently associated with adverse pregnancy outcomes, but their inter-relationships are yet to be evaluated. We aimed to investigate the associations between maternal plasma 25OHD status and sleep quality and circadian eating patterns during pregnancy. Data on pregnant women (n = 890) from a prospective cohort (Growing Up in Singapore Towards healthy Outcomes) were analyzed. Plasma 25OHD concentration was measured, while the Pittsburgh sleep quality index (PSQI) and 24-h dietary recall were administered to women at 26-28 weeks' gestation. Plasma 25OHD status was defined as sufficient (>75 nmol/L), insufficient (50-75 nmol/L), or deficient (<50 nmol/L). Poor sleep quality was defined by a total global PSQI score >5. Predominantly day-time (pDT) and predominantly night-time (pNT) were defined according to consumption of greater proportion of calories (i.e., >50%) from 07:00-18:59 and from 19:00-06:59, respectively. After adjustment for confounders, women with plasma 25OHD deficiency had higher odds of poor sleep quality (odds ratio (OR) 3.49; 95% confidence interval (CI) 1.84-6.63) and pNT eating (OR: 1.85; 95% CI 1.00-3.41) than those who were 25OHD sufficient. Our findings show the association of maternal plasma 25OHD deficiency with poor sleep quality and pNT eating at mid-pregnancy.

Predominantly nighttime feeding and weight outcomes in infants

BACKGROUND

The influence of circadian feeding patterns on weight outcomes has been shown in animal and human studies but not in very young children.

OBJECTIVE

We aimed to examine the association of infant circadian feeding patterns at 12 mo of age with subsequent growth and weight status after 1 y.

DESIGN

Mothers from a Singapore birth cohort (n = 349) reported the food given to their infants and the feeding time at 12 mo of age. Predominantly daytime (pDT) (0700-1859; n = 282) and predominantly nighttime (pNT) (1900-0659; n = 67) feeding infants were defined by whether daytime energy intake was >50% or <50% of total energy intake as assessed with the use of a 24-h recall. Body mass index-for-age z scores (BAZs) were computed with the use of the WHO Child Growth Standards 2006 to determine changes in BAZs from 12 to 24 mo of age and weight status at 24 mo of age. Multivariable linear and logistic regression analyses were performed.

RESULTS

Compared with pDT feeding, pNT feeding was associated with a higher BAZ gain from 12 to 24 mo of age (adjusted β = 0.38; 95% CI: 0.11, 0.65; P = 0.006) and increased risk of becoming overweight at 24 mo of age (adjusted OR: 2.78; 95% CI: 1.11, 6.97; P = 0.029) with adjustments for maternal age, education, ethnicity, monthly household income, parity, infant BAZ at 12 mo of age, feeding mode in the first 6 mo of life, and total daily energy intake.

CONCLUSIONS

Our study suggests that the role of the daily distribution of energy consumption in weight regulation begins in infancy. The feeding of infants predominantly during nighttime hours was associated with adiposity gain and risk of overweight in early childhood. The inclusion of advice on the appropriate feeding time may be considered when implementing strategies to combat childhood obesity. This trial was registered at clinicaltrials.gov as NCT01174875.

Predominantly night-time feeding and maternal glycaemic levels during pregnancy

Little is known about the influence of meal timing and energy consumption patterns throughout the day on glucose regulation during pregnancy. We examined the association of maternal feeding patterns with glycaemic levels among lean and overweight pregnant women. In a prospective cohort study in Singapore, maternal 24-h dietary recalls, fasting glucose (FG) and 2-h postprandial glucose (2HPPG) concentrations were measured at 26-28 weeks of gestation. Women (n 985) were classified into lean (BMI<23 kg/m2) or overweight (BMI≥23 kg/m2) groups. They were further categorised as predominantly daytime (pDT) or predominantly night-time (pNT) feeders according to consumption of greater proportion of energy content from 07.00 to 18.59 hours or from 19.00 to 06.59 hours, respectively. On stratification by weight status, lean pNT feeders were found to have higher FG than lean pDT feeders (4·36 (sd 0·38) v. 4·22 (sd 0·35) mmol/l; P=0·002); however, such differences were not observed between overweight pDT and pNT feeders (4·49 (sd 0·60) v. 4·46 (sd 0·45) mmol/l; P=0·717). Using multiple linear regression with confounder adjustment, pNT feeding was associated with higher FG in the lean group (β=0·16 mmol/l; 95 % CI 0·05, 0·26; P=0·003) but not in the overweight group (β=0·02 mmol/l; 95 % CI -0·17, 0·20; P=0·879). No significant association was found between maternal feeding pattern and 2HPPG in both the lean and the overweight groups. In conclusion, pNT feeding was associated with higher FG concentration in lean but not in overweight pregnant women, suggesting that there may be an adiposity-dependent effect of maternal feeding patterns on glucose tolerance during pregnancy.

Association of late-night carbohydrate intake with glucose tolerance among pregnant African American women

Obesity and late-night food consumption are associated with impaired glucose tolerance. Late-night carbohydrate consumption may be particularly detrimental during late pregnancy because insulin sensitivity declines as pregnancy progresses. Further, women who were obese (Ob) prior to pregnancy have lower insulin sensitivity than do women of normal weight (NW). The aim of this study is to test the hypothesis that night-time carbohydrate consumption is associated with poorer glucose tolerance in late pregnancy and that this association would be exacerbated among Ob women. Forty non-diabetic African American women were recruited based upon early pregnancy body mass index (NW, <25 kg m(-2) ; Ob, ≥30 kg m(-2) ). Third trimester free-living dietary intake was assessed by food diary, and indices of glucose tolerance and insulin action were assessed during a 75-g oral glucose tolerance test. Women in the Ob group reported greater average 24-h energy intake (3055 kcal vs. 2415 kcal, P < 0.05). Across the whole cohort, night-time, but not day-time, carbohydrate intake was positively associated with glucose concentrations after the glucose load and inversely associated with early phase insulin secretion (P < 0.05). Multiple linear regression modelling within each weight group showed that the associations among late-night carbohydrate intake, glucose concentrations and insulin secretion were present only in the Ob group. This is the first study to report an association of night-time carbohydrate intake specifically on glucose tolerance and insulin action during pregnancy. If replicated, these results suggest that late-night carbohydrate intake may be a potential target for intervention to improve metabolic health of Ob women in late pregnancy.