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Can coffee drinking prevent dementia? What about tea? Which one is better? As we learn more about the causes of dementia, answers to these questions are becoming clearer. Coffee and tea contain caffeine. The widespread availability of foods containing caffeine has led experts to suggest that 80% of all people in North America have measureable levels of caffeine in their brains from embryo to death. Thank goodness that something good does come from this situation.
Recent studies have confirmed that coffee drinking significantly lowers the risk of developing Parkinson's disease. This effect requires about five to six cups of coffee per day for many years and appears to be mostly beneficial only to males primarily due to the lower levels of estrogen. Women benefit from coffee-drinking in other ways, particularly with regard to a reduced incidence of type-2 diabetes. Overall, people who drink substantial amounts of coffee daily tend to live longer than people who do not. Coffee drinking has been correlated with a reduced incidence of colon cancer and liver cirrhosis. Recent evidence suggests that moderate coffee-drinking of about two to three cups each day might reduce your chance of developing Alzheimer's disease.
But which is better: coffee or tea? A preliminary answer to this question was recently presented at an international meeting on Alzheimer's disease by Dr. Lenore Arab an epidemiologist working at UCLA. The cognitive decline of a large group of people who regularly consume coffee or tea (about five cups of each beverage per week) was monitored for nine years. Overall, the tea drinkers exhibited a slower rate of cognitive decline than the coffee drinkers but the difference was rather modest. Their investigation also produced some truly intriguing results suggesting that the benefits of drinking coffee or tea might not be entirely related to the presence of caffeine or theophylline. Coffee and tea are rich in biologically active substances such as trigonelline and pyrogallic acid and antioxidants such as chlorogenic, coumaric, ferrulic, and sinapic acids and silverskin.
Therefore, the best advice may have been offered by the 19th Century Dutch physician Buntckuh who advised "men and women to drink tea daily, hour by hour if possible; beginning with ten cups a day, and increasing the dose to the utmost the stomach can contain and the kidneys can eliminate." Well, maybe not that much, but you get the idea.
