Serum Vitamin B₁₂ Concentrations in the General Population: A Ten‐year Follow‐up

Abstract

S ummary . Community samples of 673 subjects who had had serum vitamin B 12 concentrations measured in 1958 were followed‐up 10 yr later. 134 of these subjects had died; the death rates showed no consistent trend in relation to the original serum vitamin B 12 concentrations. Comparisons of concentrations in 1958 and 1968 in 480 subjects showed correlation coefficients ( r ) of between 0.46 and 0.71 in various subgroups. The oldest age group had a slightly lower mean concentration, and a larger proportion of this group had values below 100 pg/ml. Several subjects with a consistently low serum vitamin B 12 concentration for 10 yr maintained an apparently satisfactory circulating haemoglobin concentration.