Higher net worth at midlife linked to longevity finds JAMA study Updated On 2021-07-25T12:02:42+05:30 EVANSTON, Ill.-One of the keys to a long life may lie in your net worth, finds a new study.Net worth at midlife was associated with longevity among adults in the study, and this association is unlikely to be merely an artifact of early experiences or heritable traits shared by families. This cohort study published in Journal of American Medical Association found that wealth accumulation at midlife was associated with longevity in US adults. In the first wealth and longevity study to incorporate siblings and twin pair data, researchers from Northwestern University analyzed the midlife net worth of adults (mean age 46.7 years) and their mortality rates 24 years later. They discovered those with greater wealth at midlife tended to live longer.