COUMARIN 7-HYDROXYLATION IN LONG-TERM ADHERENTS OF A STRICT UNCOOKED VEGAN DIET

Objective: Coumarin 7-hydroxylation was investigated in 21 Finnish veg ans (20 females, one male) consuming a strict, uncooked vegan diet ('' living food diet'') and in their matched omnivorous controls, by means of an in vivo coumarin test. Method: A capsule containing 5 mg of cou marin (Venalot(R)) was taken after an overnight fast, and urine sample s were collected before and 2, 4 and 6 h after the drug administration . The extent and rate of urinary excretion of 7-hydroxycoumarin was de termined using HPLC, Results: The total urinary excretion of 7-hydroxy coumarin during 6 h was 58 (range 23-85) and 64 (range 39-92)% of the administred dose in the vegan and control groups. The coumarin index ( excretion of 7-hydroxycoumarin during the first 2 h as percentage of t otal excretion) was 72% in the vegan and 78 % in the control groups. A negative correlation was observed between the coumarin index and the consumption of wheatgrass juice by the vegans (r = -0.60, P < 0.01, n = 21), Proportion of slow hydroxylators (excreting 7-hydroxycoumarin a fter 4 h) was not statistically different between the groups (5/21 in the vegans vs 8/20 in the controls). Conclusion: According to the pres ent study, the clearly different dietary patterns and nutrient intakes between the vegans and the omnivores resulted in similar extent and r ate of 7-hydroxycoumarin formation, indicating only a minor effect on coumarin hydroxylase (CYP2A6) activity by the plant substances in the uncooked vegan diet.