The association between sugar intake during pregnancy and allergies in offspring: A systematic review and a meta-analysis of cohort studies

Context: It has been hypothesized that a mother's diet during pregnancy may modulate her offspring's immune system development and lead to development of allergic diseases among offspring. However, the evidence for this is unclear and inconclusive. Objective: This systematic review was undertaken to examine the weight of evidence for causality from cohort studies on the association between maternal free sugar intake during pregnancy and development of allergies in offspring. Data Sources: Using a systematic search strategy, PubMed, SCOPUS, and Web of Science databases were searched from inception to May 2020. Data Extraction: For the reporting of this systematic review, the PRISMA guideline was followed. Studies examining maternal sugar consumption during pregnancy (using self-reported data) and the development of allergic diseases among offspring (infancy to 5 years) were included. Data Analysis: The Newcastle-Ottawa Scale quality assessment tool was used to assess the study quality. Meta-analysis was conducted using a random-effects model to synthesize the findings. Of 159 publications identified from the search, 5 articles with 4 unique cohort studies were included in this systematic review. The limited meta-analysis showed that a mother's increased free sugar intake during pregnancy was associated with an increased risk of developing asthma in offspring (odds ratio 1.07 [95% CI, 1.00 to 1.14; I2 = 0%]). High free sugar intake by the mother during pregnancy was also associated with increased odds of offspring (to age 7.7 years) developing other common allergies, including allergic rhinitis, atopy and eczema, wheeze, and food allergies. Conclusion: From the limited evidence, this review suggests that high free sugar consumption during pregnancy may be associated with the development of allergies in offspring. Clinical guidelines and public health policy recommendations for maternal diet in pregnancy should include advice about reducing free sugar intake due to a possible association with allergies in offspring. However, recommendations should be made with caution considering other maternal and fetal risk factors.