Prenatal Mediterranean diet reduces offspring obesity

In a recent study published in Nutrients, researchers determined the relationship between maternal Mediterranean diet (MedDiet) adherence during gestation and overweight or obese offspring risk at four years.

Study: Close Adherence to a Mediterranean Diet during Pregnancy Decreases Childhood Overweight/Obesity: A Prospective Study. Image Credit: Marian Weyo/Shutterstock.com

Background

The childhood obesity epidemic is a global health concern affecting millions of children under five, causing psychological comorbidities, low self-esteem, behavioral and emotional disorders, and long-term cardiovascular morbidity and cancer.

In addition, the World Health Organization’s (WHO) report emphasizes the importance of antenatal nutritional balance in preventing childhood obesity. 

Close maternal adherence to a Mediterranean-style diet during gestation could be a promising strategy for determining potential obesity risks in childhood. Greater adherence to the diet has multiple health benefits for both mother and child.

However, studies examining the impact of prenatal diet on offspring obesity are scarce and yield varied results, warranting further research.

About the study

In the present study, researchers investigated whether maternal MedDiet adherence was associated with offspring obesity at four years and evaluated the impact of maternal factors on the association.

The team included 272 mother-child dyads from the Ensayo CLInico Para Suplementar con Hierro a EmbarazadaS (ECLIPSES) study for analysis.

The primary study outcome was offspring overweight or obese based on sex- and age-specific body mass index (BMI) z-scores above the 85th percentile using the WHO child growth standards.

The researchers obtained baseline maternal data from questionnaires during face-to-face interviews at recruitment, including medical history, age, educational level, socioeconomic status, physical activity, smoking status, and alcohol intake.

In addition to the gestational age at birth and delivery type, they obtained data on child-related variables, including sex, length, and weight at birth.

The team assessed prenatal diet using standardized 45-component food-frequency questionnaires (FFQs) at gestational weeks 12, 24, and 36 and calculated relative MedDiet (rMedDiet) scores. They measured offspring height and weight at four years.

They estimated the total daily calorie intake using the REGAL food table and determined household socioeconomic status using the Catalan classification of occupations (CCO-2011).

The researchers assessed physical exercise using the International Physical Activity Questionnaire (IPAQ) and categorized gestational weight gain (GWG) using the 2009 Institute of Medicine (IOM) recommendations.

They performed multivariate logistic regression modeling to determine the odds ratios (OR) for the association between prenatal diet and childhood obesity.

The ECLIPSES randomized clinical trial was conducted in Tarragona, Spain, from 2013 to 2017 to evaluate the efficacy of maternal iron supplementation in different dosages, adjusting for the initial hemoglobin levels during early gestation, on maternal iron status at the end of gestation.

Primary care midwives recruited 791 expecting women aged ≥18 years for the study during the initial prenatal visit (before week 12 of gestation).

Results

The mean maternal age was 32; 70% were aged ≥30, and 42% were obese or overweight, with body mass index values ≥25 kg m^-2.

Most (86%) mothers were from Spain, 44% received university-level education, 22% had high socioeconomic status, and 17% practiced smoking during pregnancy. Among the mothers, 29% showed low MedDiet adherence, whereas 23% were highly adherent.

The mean prenatal rMedDiet score was 9.80, and 26% of offspring were overweight or obese at four years, with a higher obesity prevalence among males (63%) than females (37%).

The team found significant anthropometric differences (height, weight, and body mass index) by sex. The mean body mass index and body weight of offspring at four years were 16 kg m^-2 and 18 kg, respectively.

Males had higher weight (19 versus 17 kg), BMI (16 versus 15.6), weight-for-age z scores (0.5 versus 0.1), and body mass index z-scores (0.7 versus 0.2) than females.

Overweight/obesity was less prevalent among offspring of mothers with university-level education, higher socioeconomic status, and higher gestational rMedDiet scores.

After adjusting for potential confounding variables, the team found higher prenatal MedDiet adherence related to a reduced risk of offspring being overweight or obese (OR for the highest versus lowest quartile, 0.3).

They obtained similar findings, stratifying by maternal age, early gestational BMI, educational attainment, smoking status, socioeconomic status, and GWG.

After confounder adjustment, the team found that each point increase in the prenatal MedDiet was associated with a 19% lower risk of children being overweight or obese at four years (OR, 0.8).

Smoking (OR, 2.5), pre-pregnancy overweight (OR, 2.5) or obesity (OR, 2.6), and excessive GWG (OR, 2.9) were considerably associated with offspring overweight or obese at four years.

The protective effects of MedDiet on offspring weight were higher among expecting women aged below 30 years with overweight or obese during initial gestation, those who did not smoke, and those with low socioeconomic status.

Conclusion

Overall, the study findings showed higher prenatal MedDiet adherence associated with lower reduced offspring overweight/obesity at four years, especially among university-educated mothers aged below 30 years from low socioeconomic backgrounds who did not smoke. Future studies could investigate whether the association persists across life stages.