A new report suggests that rather than avoiding caffeine, elders may want to embrace some jolts of java.
In a new epidemiological study, researchers monitored the memory and thinking processes of 124 people between the ages 65 to 88. They discovered that over the course of two-to four years of follow-up, individuals with higher blood caffeine levels avoided the onset of Alzheimer’s disease.
Moreover, coffee appeared to be the major or only source of caffeine for these individuals.
Researchers say the case control study provides the first direct evidence that caffeine/coffee intake is associated with a reduced risk of dementia or delayed onset.
Their findings will appear in an online version to be published in the Journal of Alzheimer’s Disease.
“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 lead author Chuanhai Cao, Ph.D., a neuroscientist at the University of South Florida’s College of Pharmacy.
“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.”
Researchers say the study shows this protection probably occurs even in older people with early signs of the disease, called mild cognitive impairment, or MCI. MCI is often a transitional stage between normal aging and dementia with approximately 15 percent of MCI patients progressing to full-blown Alzheimer’s disease within the course of a year.
In the study, researchers focused on study participants with MCI, because of the relative risk to develop Alzheimer’s within a few years.
Blood caffeine levels at the study’s onset were substantially lower (51 percent less) in participants diagnosed with MCI who progressed to dementia during the two- to four-year follow-up than in those whose mild cognitive impairment remained stable over the same period.
Researchers discovered that no one with MCI who later developed Alzheimer’s had initial blood caffeine levels above a critical level of 1200 ng/ml – equivalent to drinking several cups of coffee a few hours before the blood sample was drawn.
In contrast, many with stable MCI had blood caffeine levels higher than this critical level.
“We found that 100 percent of the MCI patients with plasma caffeine levels above the critical level experienced no conversion to Alzheimer’s disease during the two-to-four year follow-up period,” said study co-author Gary Arendash, Ph.D.
The researchers believe higher blood caffeine levels indicate habitually higher caffeine intake, most probably through coffee. Caffeinated coffee appeared to be the main, if not exclusive, source of caffeine in the memory-protected MCI patients, because they had the same profile of blood immune markers as Alzheimer’s mice given caffeinated coffee.
Prior studies on mice suggest that caffeine interacts with a yet unidentified component of coffee to boost blood levels of a critical growth factor that seems to fight off 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.”
Alzheimer’s pathology is a process in which protein plaques and tangles accumulate in the brain, killing nerve cells, destroying neural connections, and ultimately leading to progressive and irreversible memory loss.
Since the neurodegenerative disease starts one or two decades before cognitive decline becomes apparent, the study authors point out, any intervention to cut the risk of Alzheimer’s should ideally begin that far in advance of symptoms.
“Moderate daily consumption of caffeinated coffee appears to be the best dietary option for long-term protection against Alzheimer’s memory loss,” Dr. Arendash said. “Coffee is inexpensive, readily available, easily gets into the brain, and has few side-effects for most of us. Moreover, our studies show that caffeine and coffee appear to directly attack the Alzheimer’s disease process.”
Researchers say moderate caffeine/coffee intake also appears to reduce the risk of several other diseases of aging, including Parkinson’s disease, stroke, Type II diabetes, and breast cancer.
Controlled clinical trials are necessary to definitively demonstrate the therapeutic value of caffeine for these conditions. But the evidence toward the linkage is accumulating.
A study tracking the health and coffee consumption of more than 400,000 older adults for 13 years, and published earlier this year in the New England Journal of Medicine, found that coffee drinkers reduced their risk of dying from heart disease, lung disease, pneumonia, stroke, diabetes, infections, and even injuries and accidents.
Researchers believe ongoing investigation on the benefits of caffeine is warranted.
“If we could conduct a large cohort study to look into the mechanisms of how and why coffee and caffeine can delay or prevent Alzheimer’s disease, it might result in billions of dollars in savings each year in addition to improved quality of life,” Cao said.
Source: IOS Press