The Role of Protein Intake on the Total Milk Protein in Lead-Exposed Lactating Mothers

Protein is an essential macronutrient for the growth and development of infants. Protein levels in lactating mothers are dynamic and influenced by various factors, particularly the environment and maternal characteristics. Therefore, this study aimed to evaluate the complex correlation between maternal blood lead levels (BLLs), maternal diet, and total milk protein. The Kruskal-Wallis test was used to compare total milk protein in the three groups of lead exposure, while Spearman's correlation was used to assess the correlation between maternal diet, BLLs, and total milk protein. The multivariate analysis used multiple linear regression. The results showed that the median of maternal BLLs and total milk protein were 3.3 mu g/dL and 1.07 g/dL, respectively. Maternal protein intake and current BMI had a positive correlation with total milk protein, while BLLs had a negative correlation. BLLs >= 5 mu g/dL had the most significant impact on reducing the total milk protein (p = 0.032). However, increasing maternal protein intake can effectively maintain total milk protein levels in mothers with BLLs under 5 mu g/dL (p < 0.001). It is crucial to measure BLLs in lactating mothers residing in areas exposed to lead because high maternal protein intake can only maintain total milk protein levels when the BLLs are <5 mu g/dL.

Automated summary

Protein is vital for infant growth and development. Maternal protein levels are affected by various factors, including environmental factors and maternal characteristics. This study aimed to evaluate the correlation between maternal blood lead levels (BLLs), maternal diet, and total milk protein. The results showed that BLLs had a negative correlation with total milk protein, while maternal protein intake and BMI had a positive correlation. High BLLs significantly reduced total milk protein, but increasing protein intake maintained levels in mothers with lower BLLs. It is important to measure BLLs in lactating mothers exposed to lead and promote higher protein intake to maintain total milk protein levels.