SAN FRANCISCO: New research suggests that old age now starts at 74, with middle age lasting at least nine years longer than current estimates.
Academics from the International Institute for Applied Systems Analysis (IIASA) in Vienna, Austria, argue that old age should be measured not by age, but by how long people have left to live.
Researchers say that old age should be defined as having 15 or fewer years left to live, which for the baby boomers means that they are still middle aged until their 74th year…