The Excretion of Vitamin B1 in the Urine and Feces

Abstract
The condition of vitamin B1 excretion equilibrium is described for white rats. Rats in excretion equilibrium on levels between 15 γ and 515 γ show the following distribution of the ingested vitamin: 25 to 35% excreted via urine, 20 to 30% via feces, and the remainder unaccounted for. Animals with a previous history of low vitamin intake show a time lag before reaching excretion equilibrium. If the animal is brought to excretion equilibrium at a level between 50 to 65 γ a further increase in feeding level will show no time lag before reaching excretion equilibrium. Subcutaneous injection of 200 to 500 γ per day (rats) caused the excretion via urine of 75 to 85% of the vitamin, whereas 10-kg. dogs showed urinary excretion of only 50% of 2000 γ injected.