Comparison of the Effect of Maternal Vegetarian diets and Non-Vegetarian diets on Fat Free Mass in Neonates

Abstract

Background: Maternal nutrition during pregnancy plays a critical role in determining fetal growth and neonatal body composition. Differences in dietary patterns, particularly vegetarian versus non-vegetarian diets, may influence the development of fat-free mass in neonates.

Objective: To compare the effect of vegetarian and non-vegetarian maternal diets during pregnancy on the fat-free mass appropriate for gestational age (FFM-for-GA) in neonates.

Methods: This was a single-center, hospital-based, observational comparative study conducted in the Department of Pediatrics at Saveetha Institute of Medical and Technical Sciences (SIMATS), Chennai, between January and May 2025.

Results: The study findings revealed no significant differences in baseline maternal characteristics such as age, socioeconomic status, height, or BMI between the vegetarian and non-vegetarian groups. However, maternal weight was significantly higher among non-vegetarian mothers. Both groups had similar gestational ages at delivery and parity distribution. Dietary analysis showed that non-vegetarian mothers had significantly higher caloric, carbohydrate, and protein intake compared to vegetarian mothers, although fat intake showed only a non-significant trend toward higher values. Prenatal multivitamin use and neonatal gender distribution were comparable across groups. Importantly, neonates born to non-vegetarian mothers exhibited significantly greater fat-free mass (2.78 ± 0.29 kg vs. 2.64 ± 0.32 kg; p = 0.001), higher birth weight (3.12 ± 0.39 kg vs. 3.01 ± 0.41 kg; p = 0.014), and increased birth length (49.9 ± 2.2 cm vs. 49.2 ± 2.1 cm; p = 0.007) compared to those born to vegetarian mothers.

Conclusion: The study concludes that a non-vegetarian maternal diet during pregnancy is associated with significantly higher neonatal fat-free mass, birth weight, and length. Ensuring adequate nutritional intake in vegetarian mothers is essential to support optimal fetal growth outcomes.