Starvation negative protein balance

The urinary excretion of riboflavin is decreased in human deficiency, both in 24-hr. periods and after administration of test doses of riboflavin. Because of the close relationship between retention of riboflavin and retention of protein, excretion data must be interpreted with caution. In starvation and in conditions associated with negative nitrogen balance, riboflavin excretion is increased. 

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