Biotin supplements – especially in high doses – are often marketed for presumptive health benefits such as stimulating hair growth and treating conditions like biotinidase deficiency, diabetes, lipid disorders, and diabetic periphernal neuropathy. But high amounts of biotin in a person’s bloodstream “can interfere with laboratory tests and cause a false diagnosis of conditions including hyperthyroidism or result in a misdiagnosis of congestive heart failure,” according to a study published in the Journal of the American Medical Association.
“Clinicians may want to ask about biotin ingestion even if assay results are not suspect because biotin interferences can cause either falsely normal or abnormal results,” researchers from the University of Minnesota in Minneapolis said. “It may be advisable for patients to stop taking biotin, preferably for a week as studied herein, before undergoing laboratory testing.”
The study involved six healthy adults taking 10mg of biotin daily for one week. Researchers found biotin-associated interferences in nine of 23 biotinylated assays compared with none among 14 non-biotinylated assays.
Blood samples from participants were sent to four different clinical laboratories using different diagnostic systems. Assays were performed to assess levels of nine hormones – thyroid-stimulating hormone, total thyroxine, total triiodothyronine, free thyroxine, free triiodothyronine, parathyroid hormone, prolactin, N-terminal pro-brain natriuretic peptide, and 25-hydroxyvitamin D. Assays were also performed for two non-hormones – prostate-specific antigen and ferritin.
Researchers concluded that future studies should be done “to further clarify the extent and pharmacokinetics of ingested biotin interference on various assay platforms.”
Source: MedPage Today