Previous evidence has suggested maternal diet influences pregnancy and birth outcomes, but its role in the global epidemic of childhood obesity has not yet been characterized. Furthermore, “Although immediate lifestyle intervention in the pediatric population is essential, mounting evidence has pointed to the first 1000 days of life (from conception to 2 years old) as a critical period for preventing childhood obesity,” the researchers wrote.
To determine the associations between maternal dietary quality, inflammatory potential, and offspring adiposity outcomes, the investigators conduced an individual participant data meta-analysis that spanned 5 European countries. Seven mother-offspring cohort studies within the ALPHABET consortium were included, representing populations from Ireland, France, the United Kingdom, Poland, and the Netherlands.
Validated food frequency questionnaires (FFQs) were used to assess prepregnancy or antenatal dietary intakes of study mothers. In addition, “Pregnancy diet was further classified based on a period of assessment: early pregnancy (1st/early 2nd trimester, n = 5 cohorts) and late pregnancy (3rd trimester, n = 3 cohorts).”
To rank maternal dietary inflammatory potential, the researchers used the energy-adjusted Dietary Inflammatory Index (E-DII), which converted each mother’s dietary information to amount per 1000-kcal intake, and then linked results to a regionally representative database. A higher E-DII score indicated a more pro-inflammatory diet.
A total of 16,295 mother-child pairs were included in the analysis, with the mothers’ mean (SD) age being 30.2 (4.6) years and their body mass index (BMI), 23.4 (4.2) kg/m2 at delivery. Childhood OWOB was defined as an age-and-sex-specific BMI z-score > 85th percentile, while percentages of children classified as OWOB ranged from 8.1% to 21.6% in early childhood, 6.4% to 23.8% in mid-childhood, and 7% to 19.1% in late childhood.
- Higher early-pregnancy E-DII scores tended to be associated with a higher odds of late-childhood (10.6 [1.2] years) OWOB (OR, 1.09; 95% CI, 1.00-1.19 per 1-SD E-DII score increase)
- An inverse association was observed for late-pregnancy E-DII score and early childhood (2.8 [0.3] years) OWOB (OR, 0.91; 95% CI, 0.83-1.00)
- Higher maternal whole pregnancy Dietary Approaches to Stop Hypertension (DASH) score (higher dietary quality) was associated with a lower odds of late-childhood OWOB (OR, 0.92; 95% CI, 0.87-0.98 per 1-SD DASH score increase)
- DASH associations were of similar magnitude for early (OR, 0.86; 95% CI, 0.72-1.04) and late pregnancy (OR, 0.91; 95% CI, 0.85-0.98)
- In 2 cohorts with available data, a higher whole pregnancy E-DII and lower DASH scores were associated with a lower late-childhood fat-free mass index (FFMI) in males and a higher mid-childhood fat mass index (FMI) in females (P < .10)
Associations between DASH scores and OWOB “were robust in several sensitivity analyses and further adjustment for birth weight and childhood diet did not meaningfully alter the associations and conclusions,” the authors wrote.
Maternal diet-induced modifications of epigenetic patterns in offspring could account for the association between healthier maternal diet and lower offspring adiposity, they hypothesized. Previous research has found, “Individuals who were prenatally exposed to extreme maternal undernutrition demonstrated persistent epigenetic differences 6 decades later, as compared to their unexposed, same-sex siblings.”
Because early childhood adiposity measures were recorded at a mean age of 2.8 years in the current study, the investigators may have missed the window to detect more obvious associations between maternal diet and early infant adiposity, marking a limitation to the study.
Higher BMI may also arise from higher fat-free mass making it an imperfect measure of adiposity, and “the differential magnitude and velocity of fat and fat-free mass accretion during different growth periods further complicates the interpretation of changes in childhood BMI over time,” the researchers said.
Findings are also limited in that they mainly reflected European-born/ White women in developed countries. Future investigations should consider the effects of physical activity, gestational weight, and breastfeeding duration on the association between maternal diet and childhood OWOB.
“Promoting overall healthy dietary pattern during pregnancy may have lifelong consequences for the offspring,” the authors concluded. “Because most associations were observed at mid-childhood or later, future studies investigating in utero programming of childhood adiposity may benefit from a longer follow-up.”
Chen L-W, Aubert AM, Shivappa N, et al. Maternal dietary quality, inflammatory potential and childhood obesity: an individual participant data pooled analysis of seven European cohorts in the ALPHABET consortium. BMC Med. Published online February 22, 2021. doi:10.1186/s12916-021-01908-7