Don’t Think Too Hard — It Causes Cancer

Now that we have your attention, you can think again. Rest assured that headlines about lower risk of cancer death for people with age-related declines in memory and thinking does not mean that thinking causes cancer. In fact, it means that you need to think hard about the steady diet of headlines touting this or that association as if it represents a cause and effect.

Sensational headlines — like “Upside To Age-Related Decline In Memory – Lower Risk Of Cancer Death” — were prompted by a study of 2,627 people age 65 and older in Spain. These people were screened for cognitive function and then followed for more than 12 years. None of them had dementia at the outset. But as the study progressed, they were divided into three groups according to change in their cognitive function. One group’s thinking improved over the course of the study. One group declined. The third group fell in the middle. And the group whose thinking declined the most had the lowest rates of death from cancer — 30% lower than the group with improved function.

Of course this does not prove that losing brain function protects you from cancer. It’s simply fodder for further research and sensational headlines that sow confusion. The lead investigator, Julián Benito-León, explains:

We need to understand better the relationship between a disease that causes abnormal cell death and one that causes abnormal cell growth. With the increasing number of people with both dementia and cancer, understanding this association could help us better understand and treat both diseases.

Such findings of surprising associations are clues, not answers. The clue is to think harder and move on to experiments that will provide answers.

Click here to read more about the study and here to read the study itself.

Thirsty, photograph © Richard Taylor / flickr

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2 Responses to “Don’t Think Too Hard — It Causes Cancer”

  1. April 12, 2014 at 3:23 pm, Rose Aspalter said:

    Finally someone who distinguishes between a statistical correlation and a causal relationship! Sometimes I wondered if we couldn’t study the relationship of the brand mark of the car which is used and cardiovascular risk or cancer risk!
    It’s balsam on my scientifically bleeding heart!
    (Please note: I don’t mean: Heartbleed!)

    • April 12, 2014 at 4:04 pm, Ted said:

      Thanks for making me smile.