INTERRELATIONSHIPS BETWEEN RIBOFLAVIN AND VITAMIN-B-6 AMONG ELDERLY PEOPLE (DUTCH NUTRITION SURVEILLANCE SYSTEM)

Vitamin B-6 is considered to be a risk nutrient for elderly people. Co nversion of most naturally available vitamin B-6 to its functional coe nzyme pyridoxal 5'-phosphate (PLP) depends on riboflavin. Therefore, i nterrelations were studied between riboflavin and vitamin B-6 among 47 3 elderly people not using supplements containing B-vitamins. Habitual food consumption (assessed through dietary history with cross-check), plasma PLP levels and enzyme activities of erythrocyte glutathione re ductase (EGR) and erythrocyte aspartate aminotransferase (EAST), with and without added flavin adenine dinucleotide and PLP, respectively, w ere determined The results showed that unstimulated and stimulated EAS T activity was higher when EGR activity (both simulated and unstimulat ed) was higher Plasma PLP was positively associated with (un)stimulate d EGR activities, but these correlations were not significant probably due to the lower number of observations. Adjusted for the intake of v itamin B-6 similar observations were made for the forementioned intera ctions between the biochemical indicators. To identify the strongest c orrelates of the vitamin B-6 status indicators, stepwise regression an alysis was carried out. The results showed that in each model an indic ator of the riboflavin status was included. Our findings suggest an in teraction between the status of riboflavin and vitamin B-6 at intake l evels normally found among Dutch elderly people.