Nitrogen balance, riboflavin

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. 

RECOMMENDED DAILY ALLOWANCE OF RIBOFLAVIN. Prior to 1980, the Recommended Dietary Allowances of the Food and Nutrition Board (FNB), National Research Council-National Academy of Sciences, related the allowances for riboflavin to (1) protein allowances (1958), (2) energy intake (1964), and (3) metabolic body size (1968). In the ninth edition, 1980, the FNB concluded that the information available does not support strongly any one of these over another. In the tenth edition, 1989, the FNB listed the following factors as being known to affect the riboflavin requirements nitrogen balance, energy (work) expenditure, and pregnancy-lactation. 

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