HMM: How long older adults will live comes down to 17 often surprising factors. This is interesting:

Kraus and colleagues launched their inquiry at an opportune time, having been directed to a cache of 1,500 blood samples from a 1980s longitudinal study that enrolled older people.

The banked samples had been drawn in 1992 when participants were at least 71 years old and then stored at the NIH. They were scheduled for destruction, but the researchers arrived in time to transfer them to Duke for analysis.

The blood samples had the additional fortuitous feature of being drawn at a time that preceded the widespread use of medications such as statins, which could have skewed the results. More good luck: study participants had been followed for several years and had filled out questionnaires about their health histories and habits.

Never throw out those old samples.