Study finds smoking lowers lipid and protein in human milk

Breastfeeding Medicine

Effects of Smoking, Mother's Age, Body Mass Index, and Parity Number on Lipid, Protein, and Secretory Immunoglobulin A Concentrations of Human Milk

...Conclusion: Our study showed that smoking was associated with lower milk lipid and protein concentrations and that the parity number and BMI were associated with a change in milk lipids and proteins content, respectively."