The association of maternal plant-based diets and the growth of breastfed infants.

Background: Studies are needed to further understand how different plant-based dietary patterns of mothers relate to infant growth. Thus, we investigated the association between maternal plant-based diets and infant growth in breastfed infants during the first 4 months of life. Methods: This cross-sectional study included 290 Iranian mothers and infants. Maternal dietary intake was assessed using a 168-question validated semi-quantitative food frequency questionnaire (FFQ). Three plant-based diet indices (PDIs) were then created to evaluate dietary intakes. Eighteen food groups were classified in three main categories by scoring method: wholeplant diet, healthy plant diet, and animal and unhealthy plant diet. Results: Participants in the top tertile of unhealthy PDI (uPDI) had a lower intake of potassium,phosphorus, zinc, magnesium, calcium, folate and vitamin C, B1, B2, and B3. The upper tertileof uPDI was associated with stunting at 4-month in infants (uPDI: odds ratio [OR] = 3.27, 95%CI= 1.32, 8.10). There were no significant associations between plant-based diet scores and anthropometric indices, including weight, weight status and head circumference (P > 0.05). Conclusion: In conclusion, higher adherence to uPDI may be associated with stuntingamong Iranian infants. Other PDIs were not associated with anthropometric measures. Future studies are needed to further understand the association between plant-based diets and infant growth.