[Relationship of nutrient intake to serum enzyme activity]

Measurement of the serum enzyme activity is generally used as a screening test for hepatic and biliary diseases. The purpose of this study is to examine the use of serum enzyme activity as indices of health by analyzing relationships to changes in nutrient intakes. The results obtained were as follows: In cross-sectional studies gamma-GTP (1) and LDH-4 and -5 isozyme levels had a significant negative correlation to dietary intakes of vitamin C and protein, but total serum gamma-GTP and LDH activities had no correlation. Intake trials of these nutrients showed that high intake levels of vitamin C related to decrease in isozymes levels while low protein intake resulted in increases. Serum GPT activity had a negative relationship to vitamin C intake in men, but was not correlated with nutrient intakes in women. Serum ALP activity was affected positively with vitamin B intake in 40-79 year old men and women. There were statistically significant correlations between serum cholinesterase activity and energy, and food intake patterns.