Choline intakes exceeding recommendations during human lactation improve breast milk choline content by increasing PEMT pathway metabolites

J Nutr Biochem. 2015 Sep;26(9):903-11. doi: 10.1016/j.jnutbio.2015.03.004. Epub 2015 Apr 15.


Demand for the vital nutrient choline is high during lactation; however, few studies have examined choline metabolism and requirements in this reproductive state. The present study sought to discern the effects of lactation and varied choline intake on maternal biomarkers of choline metabolism and breast milk choline content. Lactating (n=28) and control (n=21) women were randomized to 480 or 930 mg choline/day for 10-12 weeks as part of a controlled feeding study. During the last 4-6 weeks, 20% of the total choline intake was provided as an isotopically labeled choline tracer (methyl-d9-choline). Blood, urine and breast milk samples were collected for choline metabolite quantification, enrichment measurements, and gene expression analysis of choline metabolic genes. Lactating (vs. control) women exhibited higher (P < .001) plasma choline concentrations but lower (P ≤ .002) urinary excretion of choline metabolites, decreased use of choline as a methyl donor (e.g., lower enrichment of d6-dimethylglycine, P ≤ .08) and lower (P ≤ .02) leukocyte expression of most choline-metabolizing genes. A higher choline intake during lactation differentially influenced breast milk d9- vs. d3-choline metabolite enrichment. Increases (P ≤ .03) were detected among the d3-metabolites, which are generated endogenously via the hepatic phosphatidylethanolamine N-methyltransferase (PEMT), but not among the d9-metabolites generated from intact exogenous choline. These data suggest that lactation induces metabolic adaptations that increase the supply of intact choline to the mammary epithelium, and that extra maternal choline enhances breast milk choline content by increasing supply of PEMT-derived choline metabolites. This trial was registered at as NCT01127022.

Keywords: Choline; Human milk; Isotopic labeling; Lactation; PEMT.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Biomarkers / blood
  • Biomarkers / urine
  • Choline / administration & dosage*
  • Choline / analysis
  • Choline / blood
  • Choline / metabolism
  • Cohort Studies
  • Deuterium
  • Dietary Supplements*
  • Enzyme Induction
  • Female
  • Humans
  • Lactation / blood
  • Lactation / metabolism*
  • Lactation / urine
  • Leukocytes / enzymology
  • Leukocytes / metabolism
  • Liver / enzymology
  • Liver / metabolism
  • Mammary Glands, Human / enzymology
  • Mammary Glands, Human / metabolism
  • Maternal Nutritional Physiological Phenomena*
  • Milk, Human / chemistry*
  • Milk, Human / metabolism
  • New York
  • Phosphatidylethanolamine N-Methyltransferase / chemistry
  • Phosphatidylethanolamine N-Methyltransferase / genetics
  • Phosphatidylethanolamine N-Methyltransferase / metabolism*
  • RNA, Messenger / metabolism
  • Recommended Dietary Allowances
  • Young Adult


  • Biomarkers
  • RNA, Messenger
  • Deuterium
  • PEMT protein, human
  • Phosphatidylethanolamine N-Methyltransferase
  • Choline

Associated data