Drinking coffee may ward off dementia
Drinking several cups of coffee a day may help prevent dementia.
As part of a major new study led by Harvard researchers, scientists who analyzed decades of health data found that people with the highest caffeine intake were significantly less likely to develop dementia or experience age-related cognitive decline later in life.
The findings add to growing evidence that brain health can be maintained long before symptoms appear.
Dementia affects approximately 1 in 10 adults over the age of 65 and is caused by a mix of genetic, lifestyle and environmental factors.
Previous studies have shown that cutting out alcohol, avoiding ultra-processed foods and prioritizing sleep can reduce the risk. Attention now turns to caffeine.
Researchers at Mass General Brigham, a Harvard-affiliated hospital, examined the health records of more than 130,000 Americans followed for more than 40 years. They looked at how much caffeine participants consumed from coffee, tea, soda and chocolate.
Those who consumed the most caffeine a day, equivalent to two to three cups of coffee or one to two cups of tea, had an 18 percent lower risk of developing dementia compared to people who drank little or no drink at all.
Caffeinated coffee drinkers were also 20 percent less likely to show cognitive decline and performed better on memory and thinking tests.
D., senior study author and associate scientist at Mass. General Brigham Department of Medicine. Daniel Wang said: “When we were looking for possible dementia prevention tools, we thought something as common as coffee might be a promising dietary intervention.
“Although our results are encouraging, it is important to remember that the effect size was small. Consumption of caffeinated coffee or tea may be one piece of this puzzle.”
Researchers believe that caffeine, along with polyphenols found in coffee and tea, may reduce inflammation in the brain and limit cellular damage associated with dementia.
The fact that decaffeinated drinks in particular do not provide protection suggests that caffeine itself is important.
The study, published in JAMA, was based on data from long-running studies of nurses and healthcare professionals.
More than 11,033 of the participants developed dementia during the follow-up period. But outside experts have urged caution.
Naveed Sattar, professor of cardiometabolic medicine and honorary consultant at the University of Glasgow, warned: “The biggest concern is now confounding: unmeasured factors that cannot be fully explained.
“In this case, people who drink moderate amounts of tea or coffee may lead more balanced, healthier lives overall, and it may be these broader lifestyle patterns, not the drinks themselves, that are associated with better brain health.
“There is currently no strong evidence from randomized trials that tea or coffee significantly improves known risk factors for brain health, such as blood pressure, cholesterol or glucose levels. For these reasons, I interpret these findings with great caution.
“The basics of maintaining brain health remain unchanged: maintaining good cardiovascular risk factors, eating a healthy diet, staying physically active, keeping alcohol intake low, and engaging in regular mental stimulation.”
Professor Tara Spires-Jones, Department Leader at the UK Dementia Research Institute, who was not involved in the research, added that lifestyle basics were still most important.
He said: “This is a well-conducted study that looked at data from large numbers of people over many years. But the study has significant limitations.
“Such observational studies cannot definitively prove that caffeine intake is the cause of reduced dementia risk; other factors related to coffee and tea drinking habits may be responsible.”
