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2007-8-28 18:34:50 |
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Tuesday August 7, 2007 (Foodconsumer.org) -- Drinking caffeine-loaded coffee may protect against loss of memory or thinking skills in older women, according to a study published in the August 7, 2007 issue of Neurology. The observational study found women age 65 and older who drank more than three cups of coffee daily retained better memory after the four-year study than those who only drank one cup or less per day. The correlation held up even after other factors that may affect memory were considered including such as age, education, disability, depression, high blood pressure, medications, cardiovascular disease, and other chronic illnesses. However, no association between caffeine intake and memory abilities in men was observed, according to Karen Ritchie, PhD, of INSERM, the French National Institute for Health and Medical Research, in Montpellier, France and colleagues. "Women may be more sensitive to the effects of caffeine," Ritchie said. "Their bodies may react differently to the stimulant, or they may metabolize caffeine differently." In the study, 7,000 people from three French cities had been followed for four years and their cognitive abilities were evaluated at baseline, two years and the end of the four-year study. Coffee drinking habits were also surveyed. Those who drank more than three cups of coffee a day were less likely to show decline in memory. The possible benefits seemed to increase with age. Coffee drinkers at the age of 65 years were 30 percent less likely to have memory decline compared to 70 percent less likely in those who were over 80. Arushanian EB from Stavropol Medical Academy in Russia and colleagues reported in the Jan-Feb 2003 issue of Eksperimental'naia i klinicheskaia farmakologiia that caffeine effect correlates with the mental work capacity, but depends on a number of variable factors. They also found that the effect is more significant in women. But no one should rush to drink large amounts of coffee daily to prevent loss of memory, the researchers warned, as the results did not reveal any causal relation between drinking coffee and memory. Drinking coffee may not definitely lead to better retention of memory. "While we have some ideas as to how this works biologically, we need to have a better understanding of how caffeine affects the brain before we can start promoting caffeine intake as a way to reduce cognitive decline," Ritchie said. Oddly enough, there was no association between coffee drinking and incidence of dementia, according to Ritchie and colleagues although apparently drinking coffee helped retain memory. "We really need a longer study to look at whether caffeine prevents dementia; it might be that caffeine could slow the dementia process rather than preventing it," said Ritchie. Ritchie’s finding contradicts some early studies. A number of early studies have suggested that high intake of caffeine through drinking coffee were inversely related to the risk of Alzheimer's disease, one common cause for dementia. Maia L and De Mendonca A from Hospital of Santa Maria and Laboratory of Neurosciences in Portugal reported in the July 9 2002 issue of the European Journal of Neurology that "caffeine intake was associated with a significantly lower risk for AD, independently of other possible confounding variables." The researchers studied 54 patients with probable Alzheimer's disease and 54 age-matched controls and found the patients had significantly lower daily intake of caffeine compared to the healthy controls, 74 mg versus 199 mg, for a period of 20 years. One animal study conducted by Arendash GW at The Byrd Alzheimer's Center and Research Institute in Tampa, Florida and colleagues and reported in the Nov 3, 2006 issue of Neuroscience found that moderate daily intake of caffeine may delay or reduce the risk of Alzheimer's disease. They even found long-term caffeine administration led to lower hippocampal beta-amyloid (Abeta) levels, which the researchers believe is the likely mechanism of caffeine's cognitive protection. In any event, these studies are not clinical trials, a scientist affiliated with foodconsumer.org cautioned, meaning that drinking coffee or intake of caffeine does not necessarily reduce the risk of memory loss or dementia. At least one early study suggested that long-term consumption of low dose caffeine (0.3 g/L) slowed hippocampus-dependent learning and impaired long-term memory in part through inhibiting hippocampus neurogenesis. The caffeine-memory study was conducted by Han ME and colleagues from Pusan National University in South Korea and published in the May 18, 2007 issue of Biochemistry and Biophysics Research Communications |
