A recent study conducted by Harvard University, which analyzed data from 131,821 participants over an average of 37 years, finds that regular coffee consumption is linked to a reduced risk of cognitive decline and Alzheimer's disease as one ages. The study indicates that the maximum protective benefit is observed with the consumption of around three cups of caffeinated coffee daily, with higher amounts not providing additional protection. Interestingly, decaffeinated coffee does not offer the same benefits.

In addition to coffee, tea has also been found to have protective effects against cognitive decline and dementia. The study highlights that the optimal consumption for tea is one to two cups per day, which is attributed not solely to caffeine but also to its polyphenol content, particularly catechins. These compounds are noted for their antioxidant properties, which may offer neuroprotective effects as well.

The results, published in the medical journal JAMA, demonstrate that a daily intake of 300 milligrams of caffeine may lead to an 18% reduction in the risk of developing dementia. This research underscores the potential health benefits of moderate caffeine consumption while highlighting the importance of ongoing studies to further understand the complexities of caffeine's impact on cognitive health.