Red cell volume and red cell survival in normal aged people.

Estimations of red cell and blood volumes using (51)Cr were carried out on a group of 37 people over the age of 70 who were not anaemic. Subjects with clinical conditions known to affect red cell production were excluded. The mean values for red cell and blood volumes were found to be comparable with those of a control group of young adults. Seven people had red cell volumes below the accepted range in young adults but no reason was found for this difference. Red cell survival was determined concurrently on 11 of the group and did not differ from those of young controls.