There's good news and bad news, coffee drinkers.
A new report says the liquid gold an estimated three in five Americans drinks every day could be helpful in curbing the risk for Alzheimer's disease -- but only on a short-term basis. The analysis of coffee-related Alzheimer's research was presented by the Institute for Scientific Information on Coffee, a non-profit that studies the health effects of coffee, at the Alzheimer Europe conference.
"Cognitive decline is a feature of aging, and although some changes can be expected in all of us, there is some evidence that diet and lifestyle may be related to cognition," Alzheimer Europe's vice chairperson Iva Holmerova said in a statement. "In fact epidemiological studies suggest that certain lifestyle factors and nutritional elements, including the consumption of coffee and caffeine, may help to slow age-related cognitive decline seen in the older generation."
ISIC researchers point to the caffeine and polyphenol content in coffee as the protective factors. Caffeine, they say, prevents the buildup of the protein that creates plaques and tangles in the brain, which researchers believe is one of the key causes for the memory-robbing disease. Caffeine, along with polyphenols, chemical compounds that have an antioxidant effect on the body, both reduce inflammation, which some researchers believe is the key to age-related decline.
ISIC says that while there are both short-term and long-term studies following the effects of coffee consumption on Alzheimer's risk, there are few that look at both. That's why they commissioned an assessment of a study involving around 5,000 middle-aged participants, monitoring consumption between 1989 and 1991. The follow-up period lasted from 1997 to 2011.
People who drank high amounts of coffee, defined as more than three cups, were less likely to develop dementia in a four-year follow-up, but the seeming protective effect of coffee diminished after this time. In fact, after the initial four-year follow-up period, the effect was "reversed," creating a harmful correlation between high coffee consumption and dementia incidence.
Researchers say that the short-term benefits could be due to a reverse causal effect. They suggest that the short-term benefits could be caused by delayed onset of symptoms, meaning a delayed diagnosis. But, as with all research, the study has limitations. The coffee consumption was self-reported and brewing methods were not taken into consideration.
Other coffee-related research has also found similar results. A 2012 study pointed out that while coffee can't eradicate your risk for Alzheimer's, drinking about three cups a day can slow or stop the transition from mild cognitive impairment into full-blown dementia. However, coffee can lead to problems such as higher blood pressure.
As with any good thing, just a reminder that moderation is key.