{"id":"vitamin-b1","name":"Vitamin B1 (Thiamine)","shortName":"Vitamin B1","aliases":["Vitamin B1","Thiamine","Thiamin","Thiamine Diphosphate","Thiamine Pyrophosphate","Thiamine, Whole Blood","Vitamin B1, Whole Blood","Vitamin B1 (Thiamine), Whole Blood","Thiamin (Vitamin B1), WB","Thiamine (Vitamin B1), Whole Blood","Thiamine Diphosphate (TDP)","TDP","ThDP"],"abbreviations":["B1","TDP","ThDP"],"loinc":[{"code":"74444-1","primary":true},{"code":"32554-8","primary":false},{"code":"2998-3","primary":false}],"specimen":"whole-blood","units":[{"ucum":"nmol/L","display":"nmol/L"}],"referenceRanges":[{"population":"Adults","low":70,"high":180,"unit":"nmol/L","unitDisplay":"nmol/L","note":"Whole-blood thiamine diphosphate (the active form), measured by LC-MS/MS or HPLC. Mayo Clinic Laboratories and ARUP print the same interval. There is no universally accepted cutoff for deficiency, so this is a lab reference interval, not a diagnostic threshold.","sources":[{"title":"Thiamin (Vitamin B1), WB - Test ID TDP (Mayo Clinic Laboratories Extended Catalog)","url":"https://www.testcatalog.org/show/TDP","publisher":"Mayo Clinic Laboratories"},{"title":"Vitamin B1 (Thiamine), Whole Blood (test 0080388)","url":"https://ltd.aruplab.com/Tests/Pub/0080388","publisher":"ARUP Laboratories"},{"title":"Thiamine deficiency disorders: diagnosis, prevalence, and a roadmap for global control programs","url":"https://pmc.ncbi.nlm.nih.gov/articles/PMC6392124/","publisher":"Annals of the New York Academy of Sciences","year":2018}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"Measures the active form of vitamin B1 (thiamine) in whole blood, to see whether your body has enough of this B vitamin.","url":"https://bloodtesttracker.com/markers/vitamin-b1","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}