Effect of a megadose of ascorbic acid, a meal and orange juice on the absorption of selenium as sodium selenite.

Urinary and faecal excretions of selenium were measured for five days following a dose of 1 mg Se as sodium selenite in ten young women after an overnight fast. The selenite was taken two hours before a meal or mixed with 1 g ascorbic acid; or with a continental type breakfast providing 4.5-5.6 micrograms Se and 0.6-0.8 mg Cu, with or without 200 ml orange juice (60 mg ascorbic acid). The light meal appeared to have little effect on selenite-Se absorption, and orange juice appeared even to assist it. But the availability of Se was reduced almost to zero when selenite and 1 g ascorbic acid were taken together well before the meal.