New research released this week predicts that U.S. dementia cases will double by the year 2060—meaning 42 percent, or 2 in 5 Americans age 55 and older, could have some form of the condition. By age 75, that number increases to 50 percent. The risk was "substantially" higher in women (who tend to live longer than men), Black adults, and those who are carriers of the gene variant APOE4, which is considered "the strongest risk factor gene for Alzheimer’s disease," according to the National Institute on Aging (NIA).
Published in the journal Nature Medicine, the study concluded that there is an "urgent need for policies that enhance healthy aging, with a focus on health equity"—meaning doctors believe there are everyday changes people can make to lower their risk of cognitive decline.
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By 2060, there could be 1 million new dementia cases each year.
The study's predictions are more than double previous estimates, which the researchers attribute to "unreliable documentation of the illness in health records and on death certificates, minimal surveillance of early-stage cases of dementia, and the underreporting of cases among racial minority groups, who are disproportionately vulnerable," according to a press release.
The researchers note that their findings are partly driven by the fact that people are living longer and the Baby Boomer generation is aging into the most vulnerable groups.
However, there is plenty of emerging research that supports how lifestyle factors can affect one's dementia risk. For example, a study published last year in the journal The Lancet found that 45 percent of global dementia cases are preventable, noting 14 risk factors that could be addressed.
Addressing hearing loss could especially lower one's dementia risk.
As the study notes, hearing loss and cardiac/vascular health have been identified as major contributors to dementia.
"Accumulating data from clinical trials have linked healthy lifestyle behaviors, the absence of vascular risk factors and hearing rehabilitation with improved cognitive outcomes," the researchers wrote in the study. "However, only approximately 20% of US adults are meeting recommended lifestyle and cardiovascular health targets, and only approximately 30% of older adults with hearing loss are using a hearing aid."
To this point, a 2023 study concluded that hearing aids reduced the risk of cognitive decline in almost 50 percent of adults aged 70 to 84 at high risk for dementia.
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Could drinking green tea also help stave off dementia?
Another new study, published earlier this month in the journal Nature, looked at a more specific lifestyle factor and its effect on dementia—drinking green tea.
The researchers compared green tea and coffee consumption among 8,766 participants ages 65 and up between 2016 and 2018. They used brain scans to determine the effects of the beverages.
"This cross-sectional study found a significant association between lower cerebral white matter lesions and higher green tea consumption, but not coffee consumption, in older adults without dementia, even after adjusting for confounding factors," reports the study.
More specifically, those who drank three cups of green tea per day had 3 percent fewer white matter lesions than those who drank one cup. Those who drank seven or eight cups had 6 percent fewer lesions.
Cleveland Clinic defines white matter as "nerve fibers in your brain that connect different areas of your brain to each other and to your spinal cord like highways." They note that when white matter gets damaged, these lesions can "damage important pathways," leading to memory and balance issues.
However, it should be noted that the researchers did not observe a correlation between green tea consumption and "hippocampal volume or total brain volume, which can also indicate cognitive decline," notes Science Alert. Green tea didn't affect those with the APOE4 gene variant.
A separate study published in 2020 in the journal BMC Geriatrics also found that high-frequency green tea consumption was "significantly associated with a lower prevalence of cognitive impairment in middle-aged and older individuals."
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The takeaway:
Doctors and scientists predict that U.S. dementia cases will double by the year 2060 but that certain lifestyle modifications, such as wearing hearing aids, can lessen the risk. New research also points to green tea consumption as having a positive effect on cognitive health and dementia risk.
