Measurement of food intake in children with diabetes mellitus: a comparison of protein intake and urine nitrogen.

A comparison of estimates of protein intake and urine nitrogen excretion may reveal something of the strengths and weaknesses of the dietary survey method used. To this end we have compared the protein intake calculated from a 3-day diary with 24 hr urinary nitrogen excretion in 124 children with diabetes mellitus. A positive correlation was found between these measures although this became non-significant when the boys and girls were considered separately and height, weight and age were taken into account. We conclude that the estimates of mean protein intake of the whole group was satisfactory but that of some individuals may have been poor.