Gerontology is a topic that spans multiple disciplines, such as health sciences, psychology, sociology, etc. There are a large number of library databases that might meet your needs:
CINAHL (Nursing & Allied Health)Indexes over 900 English-language journals related to nursing and the allied health disciplines from 1982 to the present. Includes some full text. Updated monthly.
Health Source: Consumer EditionInformation on many health topics including the medical sciences, food sciences and nutrition, childcare, sports medicine and general health. Includes or has links to full text.
PsycINFO (1967-present)Index and abstracts of articles, books, chapters, dissertations, and reports in psychology, 1967 to the present. Includes or has links to full text.
Psychology and Behavioral Sciences CollectionCovers information concerning topics in emotional and behavioral characteristics, psychiatry & psychology, mental processes, anthropology, and observational and experimental methods.