Evaluating the effects of seaweed consumption on maternal and fetal health: A systematic review

Maternal nutrition during pregnancy is critical for healthy birth outcomes, particularly the intake of nutrients like iodine and iron. Seaweeds are rich in these nutrients. They have long been staples in Asian diets and are gaining popularity in Western diets. Despite their benefits, iron and iodine deficiencies remain prevalent among pregnant women, infants, and vegans. A systematic review of the literature was conducted using PubMed, Google Scholar, and Web of Science to evaluate the effect of seaweed consumption on maternal and child health in women, addressing a critical nutritional gap. A comprehensive search of PubMed, Google Scholar, and Web of Science (2015–2025) identified ten relevant studies on seaweed's impact during and after pregnancy. This review uniquely integrates evidence on seaweed intake, maternal nutrition, infant outcomes, and safety considerations. Regular seaweed intake during pregnancy was linked to several health benefits. It helped lower the risk of delivering small-for-gestational-age (SGA) babies and improved hemoglobin levels in pregnant women with anemia, without significantly increasing the risk of mild thyroid issues. Seaweed is also a source of DHA, which may support fetal brain development. Seaweed consumption provided nearly 22% of the daily iodine needs for pregnant women. Additionally, seaweed intake was associated with reduced chances of developmental delays in children. However, there was a noted increase in lead (Pb) levels in breast milk linked to seaweed consumption. Overall, seaweed shows potential for enhancing maternal and newborn health outcomes, particularly by contributing to iodine and iron intake. However, current evidence remains largely associative and is limited by study design and sample size, warranting further research. Keywords: Seaweed; reproduction; maternal nutrition; birth outcomes; pregnancy