New research suggests that people who show signs of faster biological aging in their 40s may be more likely to experience memory problems years later.

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  Scientists are increasingly using so-called “aging clocks” to measure how quickly a person’s body appears to be aging. One type, known as an epigenetic clock, looks at chemical changes to DNA called DNA methylation. These changes can provide clues about biological aging that may differ from a person’s actual chronological age.
  
  
• But researchers are still trying to understand exactly what these aging clocks tell us—and how reliably they can be used to measure whether a treatment is actually slowing the aging process.
  
  
• A new study adds another piece to that puzzle by examining whether the pace of epigenetic aging is linked to future memory problems.
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  A closer look at memory in midlife
  Researchers analyzed data from 232 participants in the National Study of Daily Experiences and the Midlife in the United States study. They used DunedinPACE, an epigenetic measure designed to estimate the pace at which a person’s biological aging is progressing.
  
  
• The researchers then compared these measurements with participants’ reports of everyday memory lapses, such as forgetting a name, forgetting to take medication, or failing to remember something they had planned to do.
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  Overall, the researchers did not find a significant relationship between faster epigenetic aging and memory lapses across the entire group.
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  However, an important pattern emerged when the participants were divided by age.
  
  
• Among people in their 40s, those whose epigenetic aging was faster than average were more likely to report problems with prospective memory about a decade later. Prospective memory is the ability to remember to carry out an intention in the future, for example, remembering to make a phone call, attend an appointment, or take medication.
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  These participants also reported that their memory lapses were more irritating and had a greater impact on their daily lives.
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  Why the 40s may matter
  The findings suggest that early midlife could be an important period for long-term brain health.
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  Rather than simply looking at whether someone is biologically older than their chronological age, researchers are increasingly interested in the speed of biological aging.
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• A faster pace of aging may reflect processes occurring throughout the body that eventually affect the brain.
  
  
• The study does not prove that accelerated epigenetic aging causes memory loss. The sample was relatively small, and the researchers relied on participants’ reports of their own memory experiences rather than more comprehensive clinical measures of cognitive function.
  
  
• Still, the results raise an intriguing possibility: changes associated with aging in our 40s may provide clues about cognitive health many years later.
  
  
• Aging clocks still have a way to go
  Epigenetic aging clocks are promising research tools, but scientists caution that they are not yet a definitive measure of biological aging.
  
  
• These clocks are largely created by using machine-learning techniques to identify patterns in biological data that change with age. Researchers can find that certain DNA methylation patterns are associated with aging or disease risk without necessarily knowing exactly why those particular changes matter.
  
  
• That uncertainty is important when evaluating potential anti-aging treatments. A clock might show that a person’s biological age has changed, but researchers still need to establish whether that change genuinely reflects slower aging or improved health.
  
  
• For now, studies like this one are helping scientists understand what these measurements may and may not tell us.
  
  
• The bigger message is that the foundations of cognitive health may be laid much earlier than the age when memory problems become noticeable.