O-94 - Choline-free diet for 3 weeks depleted plasma choline and phosphatidylcholine ~30% in healthy men
O-94 — Controlled inpatient depletion-repletion design (1 wk 500 mg/day choline run-in, 3 wk deficient vs control, 1 wk repletion). Demonstrates that tissue choline stores deplete on a choline-free diet despite endogenous de novo phosphatidylcholine synthesis. See
Link to originalMethodology
Controlled inpatient depletion-repletion feeding study: healthy male volunteers hospitalized on a semisynthetic diet devoid of choline but with 500 mg/day choline for a 1-week run-in, then randomized to continued choline (control) vs no choline (deficient) for 3 further weeks, with all subjects re-supplemented in week 5. The diet carried adequate but not excess methionine (and folate), so the endogenous methyl-group and de-novo phosphatidylcholine (PEMT) pathways were not artificially starved. Objective biomarkers: plasma/erythrocyte choline and phosphatidylcholine, serum aminotransferases and other liver/renal tests, serum cholesterol.
Link to original
Why this is evidence
H-39 (essential) predicts choline pools deplete on a choline-free diet because de novo PEMT synthesis cannot cover the requirement; H-48 (not essential) predicts endogenous synthesis suffices to buffer plasma choline near-normal. A ~30% fall in plasma choline/phosphatidylcholine is the direction H-39 predicts and H-48 predicts against.