The levels of dehydroepiandrosterone (DHEA) and its sulfate ester DHEAS decrease with age after a peak around 25 yr. Animal studies as well as the first studies in humans have generated the idea that DHEA replacement in elderly subjects may have beneficial effects on well-being and cognitive functions. In the present experiment 40 healthy elderly men and women (mean age, 69 yr) participated in a double blind, placebo-controlled DHEA substitution study. For 2 weeks subjects took 50 mg DHEA daily, followed by a 2-week wash-out period and a 2-week placebo period. The treatment sequence was randomized in a cross-over design. After 2 weeks of DHEA or placebo, psychological and physical well-being as well as cognitive performance were assessed using several questionnaires and neuropsychological tests. All subjects had low DHEAS baseline levels. DHEA substitution lead to a 5-fold increase in DHEAS levels in women (from 0.67 +/- 0.1 to 4.1 +/- 0.4 micrograms/mL; P < 0.001) and men (from 0.85 +/- 0.1 to 4.5 +/- 0.4 micrograms/mL; P < 0.001). DHEA, androstenedione, and testosterone levels also increased significantly in both sexes (all P < 0.001). No significant changes were observed in insulin-like growth factor I or insulin-like growth factor-binding protein-3 levels. DHEA replacement had no strong beneficial effect on any of the measured psychological or cognitive parameters. Only women tended to report an increase in well-being (P = 0.11) and mood (P = 0.10), as assessed with questionnaires. They also showed better performance in one of six cognitive tests (picture memory) after DHEA. However, after Bonferroni alpha adjustment, this difference was no longer significant. No such trend was observed in men (P > 0.20). Likewise, no beneficial effects of DHEA substitution could be observed in any of the other tests of the neuropsychological test battery in either sex (all P > 0.20). In conclusion, the present data do not support the idea of strong beneficial effects of a physiological DHEA substitution on well-being or cognitive performance in healthy elderly individuals.