Associations of maternal fructose and sugar-sweetened beverage and juice intake during lactation with infant neurodevelopmental outcomes at 24 months

Toward Understanding and Halting Legacies of Trauma

Echoes of natural and anthropogenic stressors not only reverberate within the physiology, biology, and neurobiology of the generation directly exposed to them but also within the biology of future generations. With the intent of understanding this phenomenon, significant efforts have been made to establish how exposure to psychosocial stress, chemicals, over- and undernutrition, and chemosensory experiences exert multigenerational influences. From these studies, we are gaining new appreciation for how negative environmental events experienced by one generation impact future generations. In this review, we first outline the need to operationally define dimensions of negative environmental events in the laboratory and the routes by which the impact of such events are felt through generations. Next, we discuss molecular processes that cause the effects of negative environmental events to be initiated in the exposed generation and then perpetuated across generations. Finally, we discuss how legacies of flourishing can be engineered to halt or reverse multigenerational influences of negative environmental events. In summary, this review synthesizes our current understanding of the concept, causes, and consequences of multigenerational echoes of stress and looks for opportunities to halt them.

Associations of Maternal Prenatal Zinc Consumption with Infant Brain Tissue Organization and Neurodevelopmental Outcomes

BACKGROUND/OBJECTIVES

While studies in rat pups suggest that early zinc exposure is critical for optimal brain structure and function, associations of prenatal zinc intake with measures of brain development in infants are unknown. This study aimed to assess the associations of maternal zinc intake during pregnancy with MRI measures of brain tissue microstructure and neurodevelopmental outcomes, as well as to determine whether MRI measures of the brain mediated the relationship between maternal zinc intake and neurodevelopmental indices.

METHODS

Forty-one adolescent mothers were recruited for a longitudinal study during pregnancy. Maternal zinc intake was assessed during the third trimester of pregnancy using a 24 h dietary recall. Infant MRI scans were acquired at 3 weeks postpartum using a 3.0 Tesla scanner to measure fractional anisotropy (FA) and mean diffusivity (MD). Cognitive, language, and motor skills were assessed at 4, 14, and 24 months postpartum using the Bayley Scales of Infant Development.

RESULTS

Greater prenatal zinc intake was associated with reduced FA in cortical gray matter, particularly in the frontal lobe [medial superior frontal gyrus; β (95% CI) = -1.0 (-1.5, -0.5)], in developing white matter, and in subcortical gray matter nuclei. Greater prenatal zinc intake was associated with reduced MD in cortical gray matter and developing white matter [superior longitudinal fasciculus; -4.4 (-7.1, -1.7)]. Greater maternal zinc intake also was associated with higher cognitive development scores at 14 [0.1 (0.0, 0.1)] and 24 [0.1 (0.0, 0.2)] months of age; MRI indices of FA and MD did not mediate this relationship.

CONCLUSIONS

Maternal prenatal zinc intake was associated with more favorable measures of brain tissue microstructural maturation and cognitive development during infancy.

The transgenerational effects of maternal low-protein diet during lactation on offspring

Environmental factors such as diet and lifestyle can influence the health of both mothers and offspring. However, its transgenerational transmission and underlying mechanisms remain largely unknown. Here, using a maternal lactation-period low-protein diet (LPD) mouse model, we show that maternal LPD during lactation causes decreased survival and stunted growth, significantly reduces ovulation and litter size, and alters the gut microbiome in the female LPD-F1 offspring. The transcriptome of LPD-F1 metaphase II (MII) oocytes shows that differentially expressed genes are enriched in female pregnancy and multiple metabolic processes. Moreover, maternal LPD causes early stunted growth and impairs metabolic health, which is transmitted over two generations. The methylome alteration of LPD-F1 oocytes can be partly transmitted to the F2 oocytes. Together, our results reveal that LPD during lactation transgenerationally affects offspring health, probably via oocyte epigenetic changes.

The Impact of Excessive Fructose Intake on Adipose Tissue and the Development of Childhood Obesity

Worldwide, childhood obesity cases continue to rise, and its prevalence is known to increase the risk of non-communicable diseases typically found in adults, such as cardiovascular disease and type 2 diabetes mellitus. Thus, comprehending its multiple causes to build healthier approaches and revert this scenario is urgent. Obesity development is strongly associated with high fructose intake since the excessive consumption of this highly lipogenic sugar leads to white fat accumulation and causes white adipose tissue (WAT) inflammation, oxidative stress, and dysregulated adipokine release. Unfortunately, the global consumption of fructose has increased dramatically in recent years, which is associated with the fact that fructose is not always evident to consumers, as it is commonly added as a sweetener in food and sugar-sweetened beverages (SSB). Therefore, here, we discuss the impact of excessive fructose intake on adipose tissue biology, its contribution to childhood obesity, and current strategies for reducing high fructose and/or free sugar intake. To achieve such reductions, we conclude that it is important that the population has access to reliable information about food ingredients via food labels. Consumers also need scientific education to understand potential health risks to themselves and their children.

Differential longitudinal effects of frequent sweetened food consumption at different exposure ages on child cognitive, language, and motor development

BACKGROUND

Evidence reveals frequent sugar consumption worsens cognition in animal models, and similar effects on child development are probable. We aimed to investigate the influence of sweetened foods (SFs) on child developmental trajectories.

METHODS

The prospective cohort recruited 3-month-old children in Taiwan from 1st April 2016 to 30th June 2017. Developmental inventories including cognitive, language, and motor domains, were measured at the age of 3-,12-, 24-, and 36 months old via in-person interviews. We constructed latent growth models with covariates to estimate the influence of SFs on child development.

RESULTS

Ultimately, 4782 children (50.7% boys) were included in the statistical analysis. In the cognitive domain, consumption at one year of age significantly affected the intercept, but not the linear slope and quadratic term (intercept: estimate = -0.054, p < .001); consumption at two years of age significantly affected the intercept and quadratic term (intercept: estimate = -0.08, p < .001; quadratic term: estimate = -0.093, p = .026), but not the linear slope. In the language domain, only consumption at two years of age significantly affected the intercept (estimate = -0.054, p < .001). In the motor domain, consumption at two years of age significantly affected the linear slope and quadratic term (estimate = 0.080, p = .011 and estimate = -0.082, p = .048, respectively).

CONCLUSION

We found SFs exposure at different times has different negative effects on child development. Early exposure to SFs harmed children's cognitive function. Relatively late exposure to SFs not only deteriorated children's cognitive and language abilities but also decelerated developmental velocity in cognitive and motor domains.

The Impact of Free and Added Sugars on Cognitive Function: A Systematic Review and Meta-Analysis

A relationship between excessive sugar consumption and cognitive function has been described in animal models, but the specific effects of sugars in humans remains unclear. This systematic review and meta-analysis aimed to evaluate the current knowledge, research characteristics, and quality of evidence of studies investigating the impacts of free and added sugars on human cognition in healthy participants. The review identified 77 studies (65 experimental trials, n = 3831; 9 cross-sectional studies, n = 11,456; and 3 cohort studies, n = 2059). All cohort studies and eight of the nine cross-sectional studies found significant positive correlations between added sugar consumption and risk of cognitive impairment. Four studies identified reduced risk of cognitive impairment associated with natural fructose-containing foods. The majority of randomised control trials assessed short-term glucose facilitation effects on cognitive outcomes. The results from these studies suggest the need for a tightly regulated blood glucose level, dependent on individualised physiological factors, for optimal cognitive function. A meta-analysis of a subset of studies that assessed the impact of glucose on recall found improvements in immediate free recall compared to controls (p = 0.002). The findings highlight the potentially detrimental effect of excessive, long-term, or prenatal added sugar consumption on cognitive function. Further research is needed to examine the specific effects of free and added sugars on cognitive function.

Early life high fructose exposure disrupts microglia function and impedes neurodevelopment

Despite the success of fructose as a low-cost food additive, recent epidemiological evidence suggests that high fructose consumption by pregnant mothers or during adolescence is associated with disrupted neurodevelopment 1-7 . An essential step in appropriate mammalian neurodevelopment is the synaptic pruning and elimination of newly-formed neurons by microglia, the central nervous system's (CNS) resident professional phagocyte 8-10 . Whether early life high fructose consumption affects microglia function and if this directly impacts neurodevelopment remains unknown. Here, we show that both offspring born to dams fed a high fructose diet and neonates exposed to high fructose exhibit decreased microglial density, increased uncleared apoptotic cells, and decreased synaptic pruning in vivo . Importantly, deletion of the high affinity fructose transporter SLC2A5 (GLUT5) in neonates completely reversed microglia dysfunction, suggesting that high fructose directly affects neonatal development. Mechanistically, we found that high fructose treatment of both mouse and human microglia suppresses synaptic pruning and phagocytosis capacity which is fully reversed in GLUT5-deficient microglia. Using a combination of in vivo and in vitro nuclear magnetic resonance- and mass spectrometry-based fructose tracing, we found that high fructose drives significant GLUT5-dependent fructose uptake and catabolism, rewiring microglia metabolism towards a hypo-phagocytic state. Importantly, mice exposed to high fructose as neonates exhibited cognitive defects and developed anxiety-like behavior which were rescued in GLUT5-deficient animals. Our findings provide a mechanistic explanation for the epidemiological observation that early life high fructose exposure is associated with increased prevalence of adolescent anxiety disorders.

Association between Hyperactivity and SSB Consumption in Schoolchildren: A Cross-Sectional Study in China

Sugar-sweetened beverages (SSBs) consumption has risen significantly, which may lead to various health problems. Studies about the association between SSBs and attention-deficit/hyperactivity disorder (ADHD) in children are rare and inconsistent. We have used the two-stage cluster sampling method to select 6541 students aged 6-12. We further investigated their basic information and SSB intake. Teachers' questionnaires and parents' questionnaires were used to evaluating the hyperactive behaviors in children. We examined the associations between SSB consumption and hyperactivity index (HI) by adopting the censored least absolute deviation (CLAD) estimator. Then, we further evaluated the impacts of sex and age on the association between SSB intake and hyperactivity. Children who weekly drank SSB two or more times were associated with 0.05 (0.04, 0.07) and 0.04 (0.02, 0.06) higher scores of ln (HI+1) reported by teachers and parents, respectively, compared to non-consumers children (p for trend < 0.05). A stronger association between SSB intake and hyperactivity occurred in girls and old children. (p for interaction < 0.05). SSB intake has a positive correlation with the risk of hyperactivity in children, and the frequency of SSB consumption and hyperactivity have a dose-response relationship.

The Impact of Free Sugar on Human Health-A Narrative Review

The importance of nutrition in human health has been understood for over a century. However, debate is ongoing regarding the role of added and free sugars in physiological and neurological health. In this narrative review, we have addressed several key issues around this debate and the major health conditions previously associated with sugar. We aim to determine the current evidence regarding the role of free sugars in human health, specifically obesity, diabetes, cardiovascular diseases, cognition, and mood. We also present some predominant theories on mechanisms of action. The findings suggest a negative effect of excessive added sugar consumption on human health and wellbeing. Specific class and source of carbohydrate appears to greatly influence the impact of these macronutrients on health. Further research into individual effects of carbohydrate forms in diverse populations is needed to understand the complex relationship between sugar and health.

Association between maternal sugar-sweetened beverage consumption and the social-emotional development of child before 1 year old: A prospective cohort study

BACKGROUND

Excessive consumption of sugar-sweetened beverages (SSBs) has become an international public health issue. Adverse effects of sugary beverage consumption on both mother and child during pregnancy continue to be found. However, evidence regarding maternal SSB consumption and social-emotional development of children is lacking.

METHODS

Based on the Shenzhen Birth Cohort Study (loss rate: 10.97%), we included 985 mother-infant pairs from 2018 to 2022. All mothers had a singleton live birth without hypertension, diabetes, tumor, or serious immune system disease before pregnancy. We used a chart of frequency distribution to show maternal SSB consumption, including non-diet soda, tea drinks (not 100% tea), fruit drinks, Sugar-sweetened coffee, bubble tea, or cocoa drinks, and total SSBs. A multivariate logistic regression model was used to estimate the odds ratios of the potential delay on social-emotional development of each child was monitored at both 6 months and 12 months of age based on maternal SSB consumption.

RESULTS

Among the mothers, 728 (73.91%) drank SSBs <1 time per week, 194 (19.70%) drank SSBs 1-2 times per week, 43 (4.37%) drank SSBs 3-4 times per week, and 20 (2.03%) drank SSBs 5 or more times per week. Children aged 12 months with mothers who drank SSBs five or more times per week during pregnancy had an increased risk of potential delay on social-emotional development compared to those with mothers who drank SSBs less than once per week [odds ratio: 3.08 (1.13-8.39)]. Regarding the specific kinds of SSBs, we found that tea drinks (not 100% tea) were positively associated with potential delay on social-emotional development in children aged 6 months.

CONCLUSION

Nearly three-quarters of mothers consumed almost no SSBs during pregnancy. High SSB intake during pregnancy was associated with an increased risk of the potential delay on social-emotional development of a child at 6 and 12 months of age.

Bioactive compounds in mothers milk affecting offspring outcomes: A narrative review

BACKGROUND

Compared to the exhaustive study of transgenerational programming of obesity and diabetes through exposures in the prenatal period, postnatal programming mechanisms are understudied, including the potential role of breast milk composition linking maternal metabolic status (body mass index and diabetes) and offspring growth, metabolic health and future disease risk.

METHODS

This narrative review will principally focus on four emergent bioactive compounds [microRNA's (miRNA), lipokines/signalling lipids, small molecules/metabolites and fructose] that, until recently were not known to exist in breast milk. The objective of this narrative review is to integrate evidence across multiple fields of study that demonstrate the importance of these compositional elements of breast milk during lactation and the subsequent effect of breast milk components on the health of the infant.

RESULTS

Current knowledge on the presence of miRNA's, lipokines/signalling lipids, small molecules/metabolites and fructose in breast milk and their associations with infant outcomes is compelling, but far from resolved. Two themes emerge: (1) maternal metabolic phenotypes are associated with these bioactives and (2) though existing in milk at low concentrations, they are also associated with offspring growth and body composition.

CONCLUSION

Breast milk research is gaining momentum though we must remain focused on understanding how non-nutritive bioactive components are affected by the maternal phenotype, how they subsequently impact infant outcomes. Though early, there is evidence to suggest fructose is associated with fat mass in the 1st months of life whereas 12,13 diHOME (brown fat activator) and betaine are negatively associated with early adiposity and growth.

Association of Prenatal Sugar Consumption with Newborn Brain Tissue Organization

Animal studies have shown that exposure to excess sugar during the prenatal and postnatal periods may alter early brain structure in rat pups. However, evidence in humans is lacking. The aim of this study was to determine associations of maternal total and added sugar intake in pregnancy with early brain tissue organization in infants. Adolescent mothers (n = 41) were recruited during pregnancy and completed 24 h dietary recalls during the second trimester. Diffusion tensor imaging was performed on infants using a 3.0 Tesla Magnetic Resonance Imaging Scanner at 3 weeks. Maps of fractional anisotropy (FA) and mean diffusivity (MD) were constructed. A multiple linear regression was used to examine voxel-wise associations across the brain. Adjusting for postmenstrual age, sex, birth weight, and total energy intake revealed that maternal total and added sugar consumption were associated inversely and diffusely with infant MD values, not FA values. Inverse associations were distributed throughout all of the cortical mantle, including the posterior periphery (Bs = -6.78 to -0.57, Ps < 0.001) and frontal lobe (Bs = -4.72 to -0.77, Ps ≤ 0.002). Our findings suggest that maternal total and added sugar intake during the second trimester are significantly associated with features of brain tissue organization in infants, the foundation for future functional outcomes.

Consumption of vitamin A-deficient diet elevates endoplasmic reticulum stress marker and suppresses high fructose-induced orexigenic gene expression in the brain of male Wistar rats

OBJECTIVE

Here, we assessed the impact of vitamin A deficiency (both alone and in combination with fructose) on the retinol status, phospholipids fatty acid composition and pathways associated with the endoplasmic reticulum (ER) stress and energy homeostasis of the brain. For this purpose, weanling male Wistar rats were divided into four groups consisting of 8 rats each, except 16 for the second group and they received one of the following diets; control, vitamin A-deficient (VAD), high fructose (HFr) and HFr with VAD for 16 weeks, except half of the VAD diet-fed rats, were shifted to HFr diet, after 8 weeks period.

RESULTS

The retinol content of the whole brain remained comparable across the groups, despite a significant reduction in the plasma at the end of VAD diet feeding. However, it suppressed the HFr-induced neuropeptide Y and agouti-related peptide, while rescuing the leptin receptor mRNA. Among ER stress markers, CCAAT/Enhancer-binding protein homologues protein levels were elevated significantly in the VAD diet-fed group. Further, the long-chain polyunsaturated fatty acid levels showed an increase in the brain phospholipids across the experimental groups, compared to that of the control.

CONCLUSION

Vitamin A deficiency causes ER stress in the brain, and retinol seems to play a regulatory role in the fructose-mediated transcriptional regulation of the genes involved in energy homeostasis.