We all know the refrain, 'an apple a day keeps the doctor away.' But what about 'a coffee a day keeps dementia at bay'? According to two recent studies, your daily caffeine fix might be giving you more than just a morning perk-up. It could be keeping your cognitive decline on hold.

One study followed about 6,000 adults with their mental faculties intact, around 68 years old at the onset. Over about seven years, around 230 participants developed dementia. But those who enjoyed at least two daily cups of java were 38 percent less likely to join the dementia statistic than those who abstained from coffee. A daily dose of tea seemed to hold similar benefits, reducing dementia risk by 36 percent compared to non-tea drinkers.

"What's the secret?" you may ask. Is your latte moonlighting as a superfood? Well, it seems these beverages are packed with polyphenols, plant compounds known for their anti-inflammatory and antioxidant effects that are warmly welcomed by our brains. Or so posits Dr. Frank B. Hu, a Harvard nutrition heavyweight, who was an armchair observer in these studies.

A second study, targeting fluid intelligence (that's abstract thinking and problem solving to us laymen), tracked 8,451 adults with their brains in good nick, all 60 years old or older. They observed that 0 to 3 daily coffees were linked to a notably smaller drop in fluid intelligence compared to those indulging in four or more cups. Interestingly, with tea, even one daily cup was enough to slow the decline of fluid intelligence compared to its total absence.

Which begs the question: is it truly the caffeine doing wonders for our brains? Or perhaps it's the right balance? Dr. Glen Finney, a memory and cognition authority from the Geisinger College of Health Sciences, warns about having too much of a good thing. He clues us in to other coffee ingredients that might not play nice with our brains in large amounts, such as cafestol, which has a reputation for upping cholesterol levels and potentially meddling with cognition.

Of course, these studies are not definitive proof. Presented preliminarily at the Alzheimer’s Association International Conference in Toronto, they were not controlled experiments, and their findings have yet to be published in a medical journal. Furthermore, the exact caffeine amounts in the consumed beverages were unknown. So while the initial findings are exciting, we're strapping ourselves in for further research before declaring our favorite brews veritable brain elixirs. Nonetheless, it sounds like you've got a solid excuse to continue your brew habit. Just remember, everything in moderation.