Mediterranean Diet During Pregnancy Improves Infant Neurological Development

A mul­ti­dis­ci­pli­nary team of Spanish med­ical researchers has pub­lished the results of the sec­ond stage of a major clin­i­cal trial.

The Improving Mothers for a Better Prenatal Care Trial Barcelona (IMPACT BCN) aimed to assess whether struc­tured inter­ven­tions, focus­ing on the Mediterranean diet or mind­ful­ness-based stress reduc­tion (MBSR), could decrease the per­cent­age of new­borns born small for ges­ta­tional age (SGA) and improve other adverse preg­nancy out­comes.

The main focus of this new analy­sis was a pre­spec­i­fied sec­ondary end­point aim­ing to inves­ti­gate whether mater­nal inter­ven­tions involv­ing the Mediterranean diet or stress reduc­tion dur­ing preg­nancy could enhance neu­rode­vel­op­men­tal out­comes in off­spring at the age of two years.

The neu­rode­vel­op­men­tal eval­u­a­tion used the Bayley Scales of Infant and Toddler Development (Bayley-III), assess­ing cog­ni­tive, lan­guage, motor, social-emo­tional and adap­tive behav­ior domains. The trial analy­sis took place between July and November 2022.

The orig­i­nal trial, con­ducted in Barcelona, included 1,221 preg­nant indi­vid­u­als con­sid­ered at high risk of deliv­er­ing small for ges­ta­tional age new­borns. Enrollment occurred from February 2017 to October 2019, with fol­low-up con­tin­u­ing until deliv­ery and con­clud­ing on March 1, 2020.

While numer­ous stud­ies have demon­strated the poten­tial ben­e­fits of the Mediterranean diet in reduc­ing adverse health out­comes such as car­dio­vas­cu­lar events, dia­betes, cog­ni­tive decline and inflam­ma­tory-based dis­eases among high-risk adults, this was the first study of its kind to exam­ine the poten­tial neu­ro­log­i­cal ben­e­fits to chil­dren through mater­nal diet dur­ing preg­nancy.

Randomization placed par­tic­i­pants into three groups: a nutri­tional inter­ven­tion, a stress reduc­tion inter­ven­tion and a con­trol group receiv­ing stan­dard care.

Data col­lec­tion involved base­line and final vis­its, where par­tic­i­pants answered ques­tion­naires, pro­vided bio­log­i­cal sam­ples and had peri­na­tal data col­lected. Primary and sec­ondary end­points of the trial, includ­ing the per­cent­age of new­borns who were small for ges­ta­tional age and adverse peri­na­tal out­comes, had been pub­lished ear­lier.

The IMPACT BCN trial employed a par­al­lel, unblinded, ran­dom­ized clin­i­cal design con­ducted at BCNatal, a promi­nent cen­ter for mater­nal-fetal and neona­tal med­i­cine in Barcelona. Pregnant indi­vid­u­als at midges­ta­tion (19 to 23.6 weeks) with a high risk of deliv­er­ing small for ges­ta­tional age new­borns were enrolled.

The trial aimed to ensure gen­er­al­iz­abil­ity by record­ing race and eth­nic­ity. Randomization occurred in a one-to-one ratio in the dietary inter­ven­tion, stress reduc­tion inter­ven­tion, and con­trol groups.

The Bayley-III eval­u­a­tion showed that two-year-old chil­dren born to moth­ers who under­went struc­tured lifestyle inter­ven­tions based on the Mediterranean diet or stress reduc­tion dur­ing preg­nancy exhib­ited bet­ter scores in cog­ni­tive and social-emo­tional domains.

Notably, this is the first ran­dom­ized clin­i­cal trial eval­u­at­ing the impact of such inter­ven­tions on child neu­rode­vel­op­ment.

The dietary inter­ven­tion, rooted in the tra­di­tional Mediterranean diet adapted for preg­nancy, included monthly indi­vid­ual and group ses­sions sup­ple­mented with extra vir­gin olive oil and wal­nuts.

Stress reduc­tion par­tic­i­pants received a mind­ful­ness-based stress reduc­tion pro­gram adapted for preg­nancy, involv­ing weekly group classes, a full-day ses­sion and daily home prac­tice. Usual care par­tic­i­pants fol­lowed stan­dard preg­nancy care pro­to­cols.

The assess­ment, con­ducted at the cor­rected age of 24 months, revealed that chil­dren in the Mediterranean diet group had sig­nif­i­cantly higher scores in both the cog­ni­tive and social-emo­tional domains com­pared to the usual care group.

Children in the stress reduc­tion group showed higher scores in the social-emo­tional domain. No dif­fer­ences among the study groups were observed in lan­guage, motor and adap­tive scores.

Exploratory analy­ses of the entire study pop­u­la­tion demon­strated pos­i­tive asso­ci­a­tions between the Mediterranean diet score and cog­ni­tive and lan­guage Bayley-III domains.

A higher intake of docosa­hexaenoic acid, an omega‑3 fatty acid found in fish oils, was linked to bet­ter lan­guage scores. In com­par­i­son, higher trans fatty acid intake was inversely asso­ci­ated with social-emo­tional and lan­guage scores.

Trans fats, though nat­u­rally occur­ring in dairy prod­ucts and ani­mal fats, are more com­monly ingested in the 21^st cen­tury through the con­sump­tion of processed foods high in par­tially hydro­genated veg­etable oils.

Levels of trans fats in the blood­stream of breast­fed infants fluc­tu­ate with the amounts found in their milk, which in turn varies accord­ing to the mother’s diet. A 1999 study reported per­cent­ages of trans fats in pro­por­tion to total fats in human milk rang­ing from one per­cent in Spain to seven per­cent in Canada and the United States.

Although the authors note cer­tain lim­i­ta­tions of their study, such as the fact that par­tic­i­pants were selected from among those deemed at high risk of adverse preg­nancy out­comes, they con­clude that struc­tured mater­nal lifestyle inter­ven­tions based on the Mediterranean diet dur­ing preg­nancy con­tributed to improved cog­ni­tive and social-emo­tional scores in chil­dren at age two.

The team believes the find­ings sup­port the notion that a healthy dietary pat­tern like the Mediterranean diet may pos­i­tively influ­ence fetal neu­rode­vel­op­ment. Randomized clin­i­cal tri­als and assess­ments in addi­tional patient pop­u­la­tions will fur­ther under­stand­ing of the mech­a­nisms involved.