This study examines to what extent memory capacity is influenced by lifestyle, health or sociodemographic factors, The data were derived from the Maastricht Aging Study (MAAS), a large study carried out in The Netherlands. For the current study 1,673 people aged 24-88 years completed a postal survey on 'Health, Cognition, and Psychosocial factors'. The dependent variable was 'memory capacity' as measured by the Metamemory in Adulthood (MIA) questionnaire. The study shows that age, gender and coping abilities play an important role in influencing the variation in memory capacity. The lifestyle factors of smoking and mental activity also had a significant effect on memory capacity in certain age-specific subgroups. These results suggests that future research should focus on these variables as determinants of cognitive ageing.