Riboflavin Content of Blood and Muscle in Normal and in Malnourished Humans. ∗

Abstract

Summary and Conclusions

1. The blood riboflavin values of 20 normal subjects ranged between 0.35 and 0.45 μg per ml, with an average value of 0.42 μg per ml. The same range of riboflavin values was found in a group of 35 patients with varying degrees of riboflavin deficiency. The average value for this group was 0.40 μg of riboflavin per ml.

2. The muscle riboflavin values of 9 control subjects ranged between 2.2 and 3.5 μg per gram of fresh weight with an average value of 2.9 μg per gram. The muscle riboflavin values for 30 pellagrins lay within the same range with an average value of 2.8 μg per gram of fresh muscle.

3. From these results we have concluded that a determination of blood and muscle riboflavin values is of little significance in the evaluation of a state of riboflavin deficiency in man.