Tetracosactrin (Synacthen) tests were performed on 19 elderly women who had leucocyte ascorbic acid (LAA) levels of less than 15 μg/l08 WBC. 9 were then given a daily dose of 200 mg ascorbic acid orally for 2 weeks while the other 10 were left untreated. Following this, tetracosactrin tests were repeated in both groups. All initial plasma cortisol responses to tetracosactrin were within normal limits. Treatment with ascorbic acid produced no changes in these. This suggests that the low LAA levels often found in old people do not result in adrenal insufficiency