Researchers investigated effects of adult learning (AL) on a range of measures of health and social capital and cohesion. Data from the National Child Development Study relating to almost 10,000 adults born in Britain in 1958 were used, with focus on changes in their lives between age 33 in 1991 and 42 in 2000. Findings indicated AL played an important role in contributing to small shifts in attitudes and behaviors that occur during mid- adulthood; AL participation contributed to positive and substantial changes in health behaviors and small improvements in well-being; it did not protect against onset or progression of depression; positive effects were found in relation to two of three measures of health practices (giving up smoking and taking more exercise); effects of taking leisure courses on adoption of health practices were particularly pervasive; participation in AL may involve an element of risk to life satisfaction and psychological health; strong evidence indicated AL contributed to changes in attitudes and behaviors that promote social capital and, possibly, social cohesion; taking academic accredited courses played a particularly important role in development of attitudes promoting social capital and social cohesion; and participation in leisure courses raised race tolerance and was integral to the growth of civic participation. (Appendixes include 62 references and 33 pages of tables and figures.) (YLB)