Home ยป Tryptophan load test helps in the evaluation of the deficiency of the vitamin Vitamins MCQs Tryptophan load test helps in the evaluation of the deficiency of the vitamin January 26, 2022 63 Views Q. Tryptophan load test helps in the evaluation of the deficiency of the vitamin A. Folic acid B. Niacin C. Pyridoxine D. cyanacobalamine Answer: Pyridoxine