- A new study published in Scientific Reports shows that following a Mediterranean diet during pregnancy alters the fatty acid composition of the placenta and modifies molecular pathways involved in nutrient transport, inflammation, and placental tissue remodelling. The findings reinforce the importance of healthy lifestyle habits during pregnancy as a strategy to promote healthy pregnancy development
Pregnancy complications, such as fetal growth restriction, preeclampsia and gestational diabetes, are becoming increasingly common. This rise is partly linked to the growing prevalence of obesity and unhealthy lifestyle habits. However, therapeutic options during pregnancy are limited, as the use of medications must be very carefully controlled to avoid risks to the fetus.
A team of researchers from the Instituto de Investigaciones Biomédicas Sols-Morreale (IIBM), CSIC-UAM and the Universidad Autónoma de Madrid, led by Jorge López-Tello, in collaboration with the Universidad de Cambridge, the Universidad Complutense de Madrid and BCNatal (Hospital Clínic and Hospital Sant Joan de Déu de Barcelona), has explored whether changing maternal diet during pregnancy can influence placental biology.
The placenta: the key intermediary between mother and baby
The placenta is much more than a simple conduit between the mother and the fetus. It is a living, dynamic organ that regulates the transfer of nutrients, oxygen and biological signals to the baby, while also acting as a barrier against potential harmful insults. Its proper function is essential for fetal development and may influence the baby's health from the earliest stages of life.
The study, published in Scientific Reports, analysed placentas from women participating in the IMPACT BCN clinical trial, one of Spain's leading studies in maternal-fetal health. The results show that the placentas of women who followed a Mediterranean diet display biological characteristics that differ from those of women who maintained their usual diet.
How the Mediterranean diet changes the placenta
The placentas of mothers who followed the Mediterranean diet showed a significantly different fatty acid profile from those of mothers who followed their usual diet, together with changes in the mechanisms that regulate nutrient transport to the fetus, lipid metabolism, inflammation and the remodelling of placental tissue itself.
One of the study's most striking findings is that some of these changes depended on the baby's sex. Placentas from male fetuses showed a stronger response to the Mediterranean diet than those from female fetuses. This finding is consistent with previous studies by Jorge López-Tello's research group, which showed that male fetuses grow more rapidly in the womb and have greater demands for nutrients and oxygen. These greater demands may make their placentas more sensitive to changes in maternal diet.
"What we have found is that diet is not neutral during pregnancy. What the mother eats has direct consequences for how the placenta functions at the biological level, and this may influence how nutrients reach the baby and how it develops," explains Jorge López-Tello, principal investigator of the study.
Healthy lifestyle habits: the best medicine during pregnancy
This study adds to the growing body of evidence supporting the role of healthy lifestyle habits during pregnancy. Previous studies conducted as part of the IMPACT BCN trial had already shown that following a Mediterranean diet during pregnancy reduces the proportion of babies born with low birth weight, a complication that affects approximately 10% of births and is associated with an increased risk of developing chronic diseases later in life.
The new study provides an essential piece of the puzzle by identifying placental changes that could help explain these benefits. The Mediterranean diet, based on vegetables, fruit, legumes, nuts, extra virgin olive oil and fish, together with a reduced intake of processed meats and ultra-processed foods, thus emerges as one of the most accessible and effective strategies for promoting health during pregnancy, without the need for pharmacological treatments.
Reference: López-Tello J, Youssef L, Bermejo-Poza R, Cabezas A, De la Fuente J, Crovetto F, Gratacos E, Crispi F, Sferruzzi-Perri AN. Placental lipid handling, growth and inflammatory pathways are modified by a maternal Mediterranean diet. Scientific Reports. 2026. DOI: 10.1038/s41598-026-60877-0
Cover image: Histological section of a human placenta stained with haematoxylin and eosin.