Effects of chronicβ‐carotene supplementation on vitamin K status in adults

Abstract

Plasma vitamin K concentrations and prothrombin coagulation activity were determined in 26 normal adults who had received daily (S‐carotene supplementation (0,15,30, or 60 mg) for six months. Neither plasma vitamin K nor coagulation activity were significantly decreased at any supplementation level. Thus, chronic β‐carotene supplementation, even at high daily doses, is not expected to result in clinical vitamin K deficiency. The data suggest separate mechanisms for intestinal absorption of β‐carotene and vitamin K.