A general interest article on one of the longest-running human studies from the Washington Post: "Every year hundreds of people travel to Baltimore for an unusual purpose. ... these folks, some of whom have made this journey for decades, believe the trip is worth their time and expense because how they live - calculated according to everything from the strength of their grip to how many apples they consume in a month - may offer clues to how the rest of us might live better, longer, healthier lives. These individuals [are] participants in the Baltimore Longitudinal Study of Aging (BLSA), the country's longest-running study of aging. Since 1958, a total of more than 1,400 volunteers have agreed to regularly undergo in-depth physicals and memory and other screenings conducted by the study's physicians. The resulting data span more than half a century and are a gold mine for researchers interested in the aging process. Because of the BLSA, scientists know that signs indicating that a person could be at risk for dementia and other cognitive diseases may appear 20 years before symptoms emerge. Findings that today are common knowledge (that exercise can help reduce high blood pressure, for one) can be traced back to BLSA's annual physicals and the data analysis done by the study's scientists. Think of it as a vast historical record."