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Memory loss is one of the more distinguishing traits of dementia and progressive loss of cognitive function as we age. But the results of a study performed at the University of Wisconsin-Milwaukee and published in the September 26, 2016 issue of the Journal of Gerontology: Biological Sciences suggest there may be an easy way to prevent or delay the onset of dementia-related symptoms, including memory loss, and you may already be doing it.
The researchers followed 6,467 postmenopausal women—all of whom were free of dementia at the beginning of the study—for up to 10 years, testing and assessing their cognitive function every year. The women self-reported how much coffee, tea and cola beverage they drank each day, and the researchers used this information to estimate their caffeine intake. They found that women who consumed more than 261 mg of caffeine a day—the equivalent of about three 8-ounce cups of coffee or six cups of tea—were less likely to develop symptoms of dementia or cognitive decline.
In the past, population studies and laboratory research with animal subjects have shown caffeine to have this same protective effect against dementia, but this is the first large-scale human study to confirm those findings. The researchers point out that while the results of this study cannot be generalized to men, one earlier study of European men did find that those who reportedly drank three cups of coffee a day had lower rates of cognitive decline over a 10 year period than men who drank less or no coffee.
Three or four cups of coffee a day is considered a moderate amount and likely to be perfectly safe for most healthy people. And drinking a moderate amount can provide an array of health benefits in addition to saving you from senility. (You can read about those health benefits here.) But caffeine temporarily boosts blood pressure and may affect blood sugar levels, which can be a concern for those with or at risk of developing diabetes or heart disease, and can potentially cause stomach problems, interfere with bone mineral absorption, and disrupt sleep for some people. So before you self-medicate, ask your doctor if three, four, or more cups of coffee a day is a safe dose for you. At the same time, if you're drinking a lot of coffee every day, be sure you’re not getting additional caffeine from sources such as “energy” drinks, or supplements, or you could be putting yourself in danger of medical complications resulting from an overdose.
Reference
Driscoll I, Shumaker SA, Snively BM et al. Relationships between caffeine intake and risk for probable decline or global cognitive impairment: The women’s health initiative memory study. JGerontol A Biol Sci Med Sci. 27 Sept 2016.http://biomedgerontology.oxfordjournals.org/content/early/2016/09/20/ge…
