Space is a good place for gerontological study, because of similarities between what happens to a body in zero gravity and what happens naturally over time on Earth.

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It's a warm and wise collection of observations about growing old that Ms. Lustbader has culled from friends, clients and 30 years' experience as a gerontological social worker, professor and writer.

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The Temple study, presented at the Gerontological Society of America's annual meeting, found 25% of their subjects had "clinically relevant" levels of symptoms, yet only 8% reported having a current diagnosis of depression.

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Research for this article stems in part from my fellowship in the 2011-2012 MetLife Foundation Journalists in Aging Fellowship program created by New America Media and the Gerontological Society of America.

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