In a large group of older women, those who consumed higher amounts of caffeine had lower rates of incident dementia than those who consumed lower amounts over as many as 10 years of follow-up in a study. Researchers published their findings in The Journals of Gerontology.
“The mounting evidence of caffeine consumption as a potentially protective factor against cognitive impairment is exciting given that caffeine is also an easily modifiable dietary factor with very few contraindications,” said study lead author Ira Driscoll, PhD, a professor of psychology at the University of Wisconsin-Milwaukee. “What is unique about this study is that we had an unprecedented opportunity to examine the relationships between caffeine intake and dementia incidence in a large and well-defined, prospectively-studied cohort of women.”
The findings are based on 6467 community-dwelling women age 65 and older who self-reported their daily caffeine consumption upon enrollment in the Women’s Health Initiative Memory Study, which is funded by the National Heart, Lung, and Blood Institute.
Over up to a decade of follow-up, the women received annual assessments of cognitive function, and 388 of them were diagnosed with probable dementia or some form of cognitive impairment.
After adjusting for a number of risk factors including age, hormone therapy, sleep quality, and depression, researchers found that women who consumed above-average levels of caffeine (more than 261 mg per day) were 36% less likely to develop incident dementia. To provide perspective, the study explained that an 8-ounce cup of coffee contains 95 mg of caffeine, 8 ounces of brewed black tea contains 47 mg, and a 12-ounce can of cola contains 33 mg.
“Our findings suggest lower odds of probable dementia or cognitive impairment in older women whose caffeine consumption was above median for this group,” the researchers concluded, “and are consistent with the existing literature showing an inverse association between caffeine intake and age-related cognitive impairment.”
Driscoll I, Shumaker SA, Snively BM, et al. Relationships between caffeine intake and risk for probable dementia or global cognitive impairment: the Women’s Health Initiative Memory Study. The Journals of Gerontology. 2016 September 27;[Epub ahead of print].