Dose-response relationships regarding vitamin B-6 in elderly people: a nationwide nutritional survey (Dutch Nutritional Surveillance System).
The dietary intake and biochemical status of vitamin B-6 in 476 apparently healthy Dutch elderly people (aged 65-79 y), who were not using drugs known to affect vitamin B-6 metabolism, were evaluated. Intake of vitamin B-6 per gram protein was related to biochemical data, namely plasma pyridoxal 5'-phosphate (PLP) and cofactor stimulation of aspartate aminotransferase in erythrocytes (AST-AC). Based on a cutoff point of 2.02 for AST-AC, approximately 9% of the elderly people not using vitamin B-6 supplements had a marginal vitamin B-6 status. About 7% were using vitamin B-6 supplements. Dietary intake of vitamin B-6 per gram protein was negatively related to AST-AC. Vitamin B-6 intakes per gram protein higher than 0.020 mg were necessary to ensure an AST-AC value less than 2.02. At high PLP values AST-AC hardly varied. The results seem to indicate a higher requirement of vitamin B-6 in elderly people than in younger adults.
TNO-CIVO Toxicology and Nutrition Institute, Department of Human Nutrition, Zeist, The Netherlands.
M R
MR
Löwik
H
H
van den Berg
S
S
Westenbrink
M
M
Wedel
J
J
Schrijver
T
T
Ockhuizen
D000368:Aged; D001219:Aspartate Aminotransferases / Q000097:blood; D001774:Blood Chemical Analysis; D004305:Dose-Response Relationship, Drug; D002149:Energy Intake; D004912:Erythrocytes / Q000201:enzymology; D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands; D009749:Nutrition Surveys; D009752:Nutritional Status; D011732:Pyridoxal Phosphate / Q000378:metabolism; D011736:Pyridoxine / Q000008:administration & dosage* / Q000378:metabolism
D011732:Pyridoxal Phosphate; D001219:Aspartate Aminotransferases; D011736:Pyridoxine