Coffee May Have Many Hidden Health Benefits

Coffee May Have Many Hidden Brain Benefits

Great news for coffee drinkers. A new study is suggesting that drinking higher amounts of coffee may lower your risk of develop Alzheimer's disease. Researchers at Cowan University (ECU) in Australia investigated whether coffee intake affected the rate of cognitive decline of more than 200 Australians over a decade.

Lead investigator Dr. Samantha Gardener said results showed an association between coffee and several important markers related to Alzheimer's disease. "We found participants with no memory impairments and with higher coffee consumption at the start of the study had lower risk of transitioning to mild cognitive impairment, which often precedes Alzheimer's disease, or developing Alzheimer's disease over the course of the study," Dr. Gardener said.

Drinking more coffee gave positive results in relation to certain domains of cognitive function, specifically executive function, which includes planning, self-control, and attention. Higher coffee intake also was linked to slowing the accumulation of the amyloid protein in the brain, a key factor in the development of Alzheimer's disease.

Dr Gardener said although further research is needed, the study is encouraging because it indicates drinking coffee could be an easy way to help delay the onset of Alzheimer's disease. "It's a simple thing that people can change," she said. "It could be particularly useful for people who are at risk of cognitive decline, but haven't developed any symptoms.”

If you only allow yourself one cup of coffee a day, the study indicates you might be better off treating yourself to an extra cup. "If the average cup of coffee made at home is 240 g, increasing to two cups a day could potentially lower cognitive decline by 8% after 18 months," Dr. Gardener said. "It could also see a 5% decrease in amyloid accumulation in the brain over the same time period."

The study was unable to differentiate between caffeinated and decaffeinated coffee, nor the benefits or consequences of how it was prepared (brewing method, the presence of milk and/or sugar, etc). Researchers still don’t know which constituents of coffee are behind its seemingly positive brain effects. Though caffeine has been linked to the results, preliminary research shows it may not be the sole contributor to potentially delaying Alzheimer's disease.

A Short Brain Boost

A new study is showing that caffeine increases alertness and detection accuracy for moving targets. Caffeine also was found to improve participants' reaction times. "A lot of what happens in our environment is moving, like trying to cross a busy intersection as a pedestrian or finding something on a shelf as you're walking through the aisles of a grocery store," said Dr. Kristine Dalton of Waterloo's School of Optometry & Vision Science in Ontario, Canada. "Testing visual acuity under dynamic conditions can provide more information about our functional performance in these scenarios than traditional static visual acuity measurements alone."

Visual acuity, also known as clarity of vision or sharpness of vision, refers to a person's ability to detect and recognize small details. While both static and dynamic visual acuity provide important information about how we interact with the world around us, dynamic visual acuity skills are especially important in the many daily activities in which we, or objects around us are moving.

"While we already know that caffeine increases the velocity of rapid-eye movements, we wanted to further investigate how exactly caffeine enhances visual processing and facilitates the detection of moving visual stimuli by testing dynamic visual acuity," said study co-author Beatríz Redondo of the University of Granada's Department of Optics, Granada, Spain.

On two separate days, half of the study's participants ingested a caffeine capsule (4mg/kg) while the other half ingested a placebo capsule. Using a computer-based test designed, each participant's dynamic visual acuity skills were measured before and 60 minutes after caffeine ingestion. "Our findings show that caffeine consumption can actually be helpful for a person's visual function by enhancing alertness and feelings of wakefulness," Dalton said. "This is especially true for those critical, everyday tasks, like driving, riding a bike or playing sports, which require us to attend to detailed information in moving objects when making decisions."

Combating Cancer with Coffee

Drinking several cups of coffee every day may be linked to a lower risk of developing prostate cancer, according to a recent study. Prostate cancer is the second most common cancer, and the sixth leading cause of cancer death in men. Coffee consumption has been linked to a lower relative risk of liver, bowel, and breast cancers, but as yet, there has been no conclusive evidence for its potential role in prostate cancer risk reduction.

Researchers pooled the data from 16 studies carried out in North America, Europe and Japan. They included more than 1 million men (1,081, 586) of whom 57,732 developed prostate cancer. Compared with the lowest category of coffee consumption, the highest category was associated with a reduction in prostate cancer risk of 9%. Each additional daily cup was associated with a reduction in risk of 1%.

It showed that compared with the lowest intake, the highest intake was associated with a 7% lower risk of localized prostate cancer, and a 12% to 16% lower risk for advanced and fatal prostate cancer. Coffee improves glucose metabolism, has anti-inflammatory and antioxidant effects, and affects sex hormone levels, all of which may influence the initiation, development and progression of prostate cancer, according to the authors.

How About Tea Drinking?

Drinking coffee or tea may be associated with a lower risk of stroke and dementia, according to a new Chinese study of healthy individuals aged 50 to74.  The study was published November 16 in the open-access journal PLOS Medicine and it showed that drinking coffee was also associated with a lower risk of post-stroke dementia.

Strokes are life-threatening events, which cause 10% of all deaths globally. Post-stroke dementia is a condition where symptoms of dementia occur after a stroke. Yuan Zhang and colleagues from Tianjin Medical University, Tianjin, China studied 365,682 participants from the UK Biobank, who were recruited between 2006 and 2010 and followed them until 2020. At the outset, participants self-reported their coffee and tea intake. Over the study period, 5,079 participants developed dementia and 10,053 experienced at least one stroke.

Those who drank 2 to 3 cups of coffee or 3 to 5 cups of tea per day, or a combination of 4 to 6 cups of coffee and tea had the lowest incidence of stroke or dementia. Individuals who drank 2 to 3 cups of coffee and 2 to 3 cups of tea daily had a 32% lower risk of stroke and a 28% lower risk of dementia compared with those who drank neither coffee nor tea. Intake of coffee alone or in combination with tea was also associated with lower risk of post-stroke dementia. The findings indicate that moderate consumption of coffee and tea separately or in combination were associated with an overall lower risk of stroke and dementia. 

John Schieszer is an award-winning national journalist and radio and podcast broadcaster of The Medical Minute.  He can be reached at medicalminutes@gmail.com.