A 20-year study of 1,400 Finnish people has found that those who drank three to five cups of coffee a day in middle age were two-thirds less likely than non-coffee drinkers to develop dementia. It was not clear from the study whether it was the coffee itself that lowered dementia risk or another factor common to coffee drinkers. Coffee drinking is believed to lower the risk of developing type 2 diabetes which is in turn linked to Alzheimer's. Coffee also contains antioxidants such as chlorogenic acid that may prevent cell damage over time and caffeine blocks receptors for a chemical called adenosine which has depressant effects in the central nervous system.
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