Cognitive Decline Sets in around Age 45

A new study finds that the inevitable cognitive decline we all face starts earlier than we originally thought. Christie Nicholson reports

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When people over 65 show losses in their short-term memory and comprehension, it’s no surprise. But a new study claims that a general cognitive decline starts to set in as early as age 45. The research is in the British Medical Journal

Scientists tracked more than 5,000 men and 2,000 women, between ages 45 and 70, for 10 years starting in 1997.

The study subjects were tested three times over the 10 years, for memory, vocabulary and comprehension skills. For instance, as a test of comprehension they were asked to recall as many words and animal names beginning with the letter “S” as possible.


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The participants’ scores went down in all categories except vocabulary. Both men and women who were between 45 and 49 at the start of the study experienced a 3.6 percent decline in mental ability over the decade.

Research shows that active lifestyles, both mentally and physically, slow down brain aging. Scientists thus feel it’s important to know when mental decline typically starts so that people who are getting older—and that’s all of us—can be encouraged to get active sooner rather than later. And have a decent chance to find those car keys.

—Christie Nicholson

[The above text is a transcript of this podcast.]

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