(CBS News) Is coffee a cure-all for chronic disease? Previous studies have tied drinking coffee to protective benefits against Parkinson's disease, stroke, diabetes, heart disease and some cancers.
Now, new research shows drinking about three cups of coffee each day might stave off Alzheimer's for older adults experiencing memory declines.
The study of 124 older adults with mild cognitive impairment ages 65 to 88 found that caffeine and coffee intake was associated with a reduced risk of developing dementia or a delayed onset of the disease.
Mild cognitive impairment (MCI) occurs in older people in which they display early signs of dementia such as memory loss that's beyond normal amounts expected in aging but can still perform daily activities, according to the Mayo Clinic. The condition often progresses into Alzheimer's within a few years.
Over a two to four year follow-up in the study in which researchers examined blood caffeine levels among participants, they found that participants with MCI who progressed to dementia had 51 percent lower caffeine levels compared with those with MCI who remained stable. Their findings are published in the June 5 issue of Journal of Alzheimer's Disease.
The researchers identified a "critical level" of caffeine needed to provide protective benefits of 1200 nanograms per milliliters - about the caffeine equivalent of drinking several cups of coffee a few hours before blood samples were drawn. Among participants who developed Alzheimer's, no one had a blood caffeine levels among this threshold. Meanwhile many participants with MCI that hadn't progressed had blood caffeine levels higher than the critical level.
"These intriguing results suggest that older adults with mild memory impairment who drink moderate levels of coffee - about 3 cups a day - will not convert to Alzheimer's disease or at least will experience a substantial delay before converting to Alzheimer's," said study author Dr. Chuanhai Cao, a neuroscientist at the University of South Florida Health Byrd Alzheimer's Institute, said in a written statement. "The results from this study, along with our earlier studies in Alzheimer's mice, are very consistent in indicating that moderate daily caffeine/coffee intake throughout adulthood should appreciably protect against Alzheimer's disease later in life."
Cao's animal research dating back to 2006 suggests caffeine interacts with an unidentified component in coffee to boost levels of a growth factor in the blood that seems to stall the Alzheimer's disease process.
"We are not saying that moderate coffee consumption will completely protect people from Alzheimer's disease," Cao cautioned. "However, we firmly believe that moderate coffee consumption can appreciably reduce your risk of Alzheimer's or delay its onset."
With few side effects, the researchers say coffee is a safe an inexpensive way to offer dietary protection against Alzheimer's memory loss.
A recent study of 400,000 people found compared to those who drank no coffee, men who had two or three cups a day were 10 percent less likely to die at any age and women were 13 percent less likely to die from conditions such as heart or respiratory disease, stroke, diabetes, injuries, accidents or infections.