The effect of prenatal exposure to Ramadan on children's height

[Intermittent fasting: effects in diverse clinical settings]

Introduction

Introduction: intermittent fasting plans propose to limit food intake during specific periods as nutritional therapeutic strategies to treat different metabolic conditions in various clinical entities. However, the heterogeneity between each context of intermittent fasting could generate different results in metabolic parameters. Objective: to evaluate the clinical application of intermittent fasting and to discern whether it offers advantages over other traditional strategies. Methods: structured questions were formulated (PICO), and the methodology followed the guidelines established by the PRISMA 2020 statement. The search was conducted in different databases (PubMed, Cochrane Library and Google Scholar). Results: we found 3,962 articles, of which 56 were finally included; 3,906 articles that did not directly or indirectly answer the structured questions were excluded. Conclusions: compared to conventional diets, the various AI schemes do not generate advantages or disadvantages in terms of weight loss and lipid profile, although in the alternate-day variant there are greater insulin reductions than those observed in the continuous energy restriction. The heterogeneity of the interventions, the populations studied, the comparators, the results, and the type of design make it impossible to extrapolate the effects found in all clinical scenarios and generalize the recommendations.

Dust to Feed, Dust to Gray: The Effect of in Utero Exposure to the Dust Bowl on Old-Age Longevity

Intensive agriculture and deep plowing caused topsoil erosion and dust storms during the 1930s, affecting agricultural income and land values for years. Given the growing literature on the relevance of in utero and early-life exposures, it is surprising that studies focusing on links between the Dust Bowl and later-life health have produced inconclusive and mixed results. We reevaluate this literature and study the long-term effects of in utero and early-life exposure to topsoil erosion caused by the 1930s Dust Bowl on old-age longevity. Specifically, using Social Security Administration death records linked with the full-count 1940 census, we conduct event studies with difference-in-differences designs to compare the longevity of individuals in high- versus low-topsoil-erosion counties before versus after 1930. We find intent-to-treat reductions in longevity of approximately 0.85 months for those born in high-erosion counties after 1930. We show that these effects are not an artifact of preexisting trends in longevity. Additional analyses suggest that the effects are more pronounced among children raised in farm households, females, and those whose mothers had lower education. We also provide suggestive evidence that reductions in adulthood income are a likely mechanism for the effects we document.

Ramadan during pregnancy and neonatal health-Fasting, dietary composition and sleep patterns

BACKGROUND AND OBJECTIVES

Large shares of pregnant Muslims worldwide observe the Ramadan fast. Previous research showed that Ramadan during pregnancy is associated with adverse offspring health outcomes lasting throughout the life-course. Evidence on effects on birth outcomes is inconclusive, however, and previous research did not consider the role of dietary composition and sleep patterns during Ramadan. This study systematically documents maternal lifestyle during Ramadan and assesses if diet and sleep adaptations to Ramadan, independent of and in addition to maternal fasting, are associated with neonatal health outcomes.

METHODS

This study reports a survey of 326 Muslims who delivered their baby in Mainz, Germany, linked to maternal & infant hospital records. Participants reported on fasting, dietary composition and sleep schedules while pregnant during Ramadan.

RESULTS

Fasting during pregnancy was associated with reduced birthweight, in particular for fasting during the first trimester (-352ˑ92g, 95% CI: -537ˑ38; -168ˑ46). Neither dietary composition nor altered sleep were directly associated with birthweight. However, dietary composition during Ramadan outside of fasting hours seems to moderate the fasting-birthweight association, which disappeared for women switching to high-fat diets.

CONCLUSIONS

The finding that dietary intake during Ramadan potentially moderates the fasting-birthweight association is of high relevance to pregnant Muslims who wish to fast and their healthcare professionals, since dietary choices outside of fasting hours are often relatively easily modifiable. This is the first study to include information on maternal diet and sleep during Ramadan, and additional research is needed to assess the roles of specific (macro)nutrients and food groups.

Long-Term Outcomes of in Utero Ramadan Exposure: A Systematic Literature Review

Health outcomes of in utero Ramadan exposure have been reported in a systematic literature review; however, the available literature on long-term effects were not fully covered. Our study aims to specifically review the long-term outcomes of in utero Ramadan exposure. We searched for original research articles analyzing any long-term outcome of in utero Ramadan exposure, excluding maternal and perinatal outcomes. Sixteen studies from 8304 non-duplicate search results were included. Most studies suggest negative consequences from in utero Ramadan exposure on health, as well as on economic outcomes later in adulthood. Higher under-five mortality rate, higher mortality under three months, and under one year, shorter stature, lower body mass index, increased incidence of vision, hearing and learning disabilities, lower mathematics, writing and reading scores, as well as a lower probability to own a home were associated with Ramadan exposure during conception or the first trimester of pregnancy. Furthermore, age and sex seem to play a pivotal role on the association. Existing studies suggest that in utero Ramadan exposure may adversely impact long-term health and economic well-being. However, evidence is limited. Meanwhile, increasing awareness of the potential risks of Ramadan fasting during pregnancy should be raised among pregnant women and clinicians and other antenatal care workers should promote better maternal healthcare.

Ramadan Fasting during Pregnancy and Health Outcomes in Offspring: A Systematic Review

Ramadan is one of the five pillars of Islam, during which fasting is obligatory for all healthy individuals. Although pregnant women are exempt from this Islamic law, the majority nevertheless choose to fast. This review aims to identify the effects of Ramadan fasting on the offspring of Muslim mothers, particularly on fetal growth, birth indices, cognitive effects and long-term effects. A systematic literature search was conducted until March 2020 in Web of Science, Pubmed, Cochrane Library, Embase and Google Scholar. Studies were evaluated based on a pre-defined quality score ranging from 0 (low quality) to 10 (high quality), and 43 articles were included. The study quality ranged from 2 to 9 with a mean quality score of 5.4. Only 3 studies had a high quality score (>7), of which one found a lower birth weight among fasting women. Few medium quality studies found a significant negative effect on fetal growth or birth indices. The quality of articles that investigated cognitive and long-term effects was poor. The association between Ramadan fasting and health outcomes of offspring is not supported by strong evidence. To further elucidate the effects of Ramadan fasting, larger prospective and retrospective studies with novel designs are needed.

The Impact of Prenatal Exposure to Ramadan on Child Anthropomorphic Outcomes in Pakistan

OBJECTIVES

This study analyzes the intent-to-treat effect of prenatal exposure to Ramadan (the Islamic month of fasting) on outcomes including stunting and underweight for children under age 5 years in Pakistan born between 2003 and 2018.

METHODS

The study uses observational data from four rounds of the UN-supported Multiple Indicator Cluster Survey (MICS) data collected on 204,186 children under-5 from Punjab, Pakistan in 2007-2008, 2010-2011, 2013-2014, and 2017-2018. Excluding data on outliers and observations with incomplete data, multivariate logistic regression analysis was conducted on the appended cross-sectional data of 179,943 children under-5 to assess the risk of stunting or underweight according to the month of gestation coinciding with Ramadan.

RESULTS

We observe a significant increase in the risk of stunting and underweight associated with exposure to Ramadan following an inverted-U pattern. The peak impact of Ramadan exposure on a child being underweight occurs in the third month of pregnancy, where the probability of being underweight is 20 percent higher as compared to children whose gestation did not coincide with Ramadan. The peak impact of Ramadan exposure on stunting occurs in the fourth month of pregnancy, where the probability of stunting is 22 percent higher as compared to children whose gestation did not coincide with Ramadan. These results vary little by gender. In contrast, exposure to Ramadan in the ninth month of gestation is associated with a reduction in the risk of stunting for boys and underweight for both boys and girls.

CONCLUSIONS FOR PRACTICE

Our analysis indicates that prenatal exposure to Ramadan during the first two trimesters have negative implications for children's growth. The study highlights the critical role of maternal habits during early pregnancy, especially nutritional intake, for the long-term physical development of children.

Women's fasting habits and dietary diversity during Ramadan in rural Bangladesh

Little is known about fasting practices and dietary changes during Ramadan in low‐ and lower‐middle‐income countries. Although pregnant women are exempt from fasting, they may still fast. This is of interest as dietary habits during pregnancy may affect the development of the unborn child. In a community‐based sample of young women in rural Sylhet division, Bangladesh, we described fasting practices and beliefs (n = 852). We also examined reported food group consumption and minimally adequate dietary diversity for women (MDD‐W) by Ramadan occurrence (n = 1,895) and by fasting adherence (n = 558) using logistic regression with Hindu women as a seasonal control.

During Ramadan in 2018, 78% of pregnant Muslim women fasted every day. Over 80% of Muslim women believe that they should fast during pregnancy and over 50% expect positive health effects on the mother and the unborn child. We found strong evidence that Muslim women have more diverse diets during Ramadan, with higher odds of MDD‐W (OR [95% CI]: 5.0 [3.6, 6.9]) and increased consumption of pulses, dairy, fruit, and large fish. Dietary diversity increased to a lesser extent on non‐fasting days during Ramadan. Ramadan appears to improve dietary quality in both fasting and non‐fasting Muslim women in a rural population in Bangladesh. These results help to interpret findings from studies on Ramadan during pregnancy on later‐life outcomes and thus contribute to a better understanding of intrauterine influences of maternal nutrition on healthy child development.

Short-term fetal nutritional stress and long-term health: Child height

OBJECTIVE

This study examined the impact of in utero exposure to Ramadan, the Islamic fasting month, by trimester on height at ages 0 to 18 for a sample of children from Tehran, Iran. If exposure to Ramadan is associated with significant nutritional stress to the fetus, the fetus's adaptive responses to nutritional insufficiency could manifest as changes in height during childhood, long before any effects on aging or disease risk at older ages.

METHODS

Children who were exposed and not exposed to Ramadan in utero were compared to identify any systematic difference between their parents' and households' characteristics (including height, age, education, and indicators of wealth). Also, the seasonal pattern of food consumption in Tehran was analyzed. Finally, the association of child height with prenatal exposure to Ramadan was measured, controlling for seasonality and parent and household.

RESULTS

Ramadan associated fasting in the second trimester of gestation was associated with 0.091 age-adjusted SDs (ie, 0.60-0.67 cm) decrease in children's height at age 10 years or older. The negative association was largest in male children and was approximately 1 cm at age 12 years or older among male children.

CONCLUSION

Maternal Ramadan fasting in the second trimester, the critical period for long bone development, was associated with decreased height. Exposure to ritual fasting is important because approximately 75% of all Muslim children are exposed to Ramadan in utero.

Were there long-term economic effects of exposure to polio vaccination? An analysis of migrants to Sweden 1946-2003

Recent research showed that exposure to the vaccine against polio in early life had no long-term economic benefits among native Swedes. However, whether this result holds for individuals from other countries remains unexplored. This study explores the relationship between exposure to the vaccine and later-life outcomes, but focuses on individuals who migrated to Sweden (birth cohorts 1946-1971), and constitute a diverse sample in terms of national origin. Using a differences-in-differences approach and register data from the Swedish Longitudinal Immigrant Database, this study explores if being exposed to the vaccine against polio in the year of birth in the country of origin has any impact on adult income, educational achievement, or days or number of hospitalizations. The results are in line with the previous research in showing that there are no statistically significant effects on adult income, education, or health from exposure to the vaccine against polio, regardless of national origin. Furthermore, no scarring effects of exposure to polio epidemics were found on any of the outcomes, reinforcing the hypothesis that polio did not scar individuals in the same way as other contemporary epidemic diseases did, and that the lack of scarring could explain the absence of long-term impact from vaccine exposure.

The impact of early-life shocks on adult welfare in Brazil: Questions of measurement and timing

Recent literature provides evidence that income shocks early in life can have long-run consequences on adult welfare. Rural Brazil frequently suffers from rainfall variations that negatively impact vulnerable households, who often lack the means for coping with these events. This paper evaluates how early-life rainfall shocks influence adult health and socioeconomic outcomes in Brazil. We find evidence that several critical periods can produce long-run consequences. Using rainfall deviations, our two most robust results are that greater rainfall in utero negatively impacts adult incomes (finding that a one standard deviation increase in rainfall causes adult incomes to fall by 7-10 percent) and that greater rainfall in the second and third years of life improve adult health (increasing body mass index by 0.16). However, our results depend crucially on our choices regarding two features. First, our results differ across two common measures of critical periods, which are used to define shocks relative to the timing of one's birth. Second, the way rainfall variation is measured also matters, with use of an extreme weather indicator suggesting heterogeneous effects by gender, with extreme weather negatively impacting women's health (both before and after birth) but positively affecting several men's outcomes (both before and after birth). We find some evidence that mortality selection may drive some of these results. This paper provides further evidence that early-life shocks (from in utero through the third year of life) can cause long-run consequences, but also suggests that more attention should be paid to the specific measurement and timing of rainfall shocks.

The long-term economic effects of polio: Evidence from the introduction of the polio vaccine to Sweden in 1957

This study explores the impact an exogenous improvement in childhood health has on later-life outcomes. Using extensive and detailed register data from the Swedish Interdisciplinary Panel covering up to 2011, we follow individuals exposed to the introduction of the first vaccine against polio in Sweden (birth cohorts 1937-1966) until adulthood in order to quantify the causal effect of polio vaccination on long-term economic outcomes. The results show that, contrary to what has been found in the literature for other health-related interventions, including other vaccines, exposure to the vaccine against polio did not seem to have any long-term effects on the studied adult economic outcomes. Upon closer inspection of how the disease affects children, this might be explained by the fact that no scarring effects from exposure to high incidence of polio were found on adult income, educational achievement, or hospitalizations, which seems to suggest that those who contracted the illness but suffered only the milder symptoms of the disease made a full recovery and had no lifelong sequels as a consequence of the condition. The absence of scarring effects is hypothesized to be related to the pathology and epidemiology of the disease itself, which infects many, but scars only those who suffer the most recognizable paralytic symptoms.

Adult body height as a mediator between early-life conditions and socio-economic status: the case of the Dutch Potato Famine, 1846-1847

Adult body height appears to be a relatively accurate summary variable of early-life exposures' influence on health, and may be a useful indicator of health in populations where more traditional health-related indicators are lacking. In particular, previous studies have shown a strong, positive relationship between environmental conditions in early life (particularly nutritional availability and the disease environment) and adult height. Research has also demonstrated positive associations between height and socioeconomic status. We therefore hypothesize that height mediates the relationship between early-life conditions and later-life socio-economic outcomes. We also hypothesize that the period of exposure in early life matters, and that conditions during pregnancy or the first years of life and/or the years during puberty have the largest effects on height and socio-economic status. To test these relationships, we use a sample of 1817 Dutch military conscripts who were exposed during early life to the Dutch Potato Famine (1846-1847). We conduct mediation analyses using structural equation modelling, and test seven different time periods in early-life. We use potato prices and real wages to proxy early-life environmental conditions, and occupational status (using the HISCAM scale) to proxy socioeconomic status. We find no evidence of mediation, partial or full, in any models. However, there are significant relationships between potato prices in adolescence, height and socio-economic status. To determine causality in these relationships, further research is needed.