pregnant woman eating

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KOFU, Japan — Maternal malnutrition, linked to a host of diseases in children as they grow up, continues to be a significant problem on a global scale. Now, new research out of Japan has uncovered another danger tied to undernutrition during pregnancy. Mothers not getting enough fiber during pregnancy displays a troubling connection to developmental delays in their children.

A series of animal studies previously indicated a low-fiber diet during pregnancy may impair brain nerve function in offspring. Now, the first human study focusing on the relationship between maternal nutritional imbalance and infants’ brain development is investigating if the same effects can be found in humans.

“Most pregnant women in Japan consume far less dietary fiber than what is the recommended intake,” says Dr. Kunio Miyake, a researcher at the University of Yamanashi and first study author, in a media release. “Our results provided reinforcing evidence that undernutrition during pregnancy is associated with an increased risk of neurodevelopmental delay in children.”

The research team compared neurodevelopment among children whose mothers had the highest intake of dietary fiber with others born to mothers who consumed successively less fiber during pregnancy.

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Compared to the high-fiber group, the children of mothers in the low-fiber groups were more likely to show neurodevelopmental delays. The impact of maternal fiber undersupply was noticeable across several domains related to brain function, including communication skills, problem-solving skills, and personal-social skills. Study authors also discovered delays in the development of large body part movement and coordination, and the coordination of smaller muscles.

These findings are based on an analysis of over 76,000 mother-infant pairs provided by the Japan Environment and Children’s Study, an ongoing project aimed at studying and better understanding how the environment affects children’s health.

To collect dietary data from participants, the research team used a food frequency questionnaire that asked respondents about their dietary status during the second and third trimesters of pregnancy. Developmental delays were assessed by another survey sent to parents once their child turned three years-old. Based on those responses, study authors found a correlation between maternal fiber intake and child brain development.

In Japan, study authors say the average dietary fiber intake is just over 10 grams daily. Just 8.4 percent of pregnant Japanese women eat enough fiber. Study authors also pointed out that the recommended fiber intake for pregnant women varies from country to country. In Japan, the recommended daily dietary fiber intake is 18 grams, but it’s 28 grams in the United States and Canada.

“Our results show that nutritional guidance for pregnant mothers is crucial to reduce the risk of future health problems for their children,” Dr. Miyake explains.

Study authors also note this project was limited in certain ways.

“Human studies cannot assess the effects of dietary fiber alone. Although this study considered the impact of folic acid intake during pregnancy, the possibility of other nutrients having an impact cannot be completely ruled out,” Dr. Miyake concludes. “In addition, dietary fiber intake from supplements could not be investigated.”

The study is published in Frontiers in Nutrition.

About John Anderer

Born blue in the face, John has been writing professionally for over a decade and covering the latest scientific research for StudyFinds since 2019. His work has been featured by Business Insider, Eat This Not That!, MSN, Ladders, and Yahoo!

Studies and abstracts can be confusing and awkwardly worded. He prides himself on making such content easy to read, understand, and apply to one’s everyday life.

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