Coffee as Functional Food: Does Brewing Method Matter?

Coffee is one of the most widely consumed beverages globally, and it is increasingly recognized for its potential as a functional food due to its rich content of bioactive compounds. Coffee contains polyphenols, diterpenes, and alkaloids that have been linked to numerous health benefits, including antioxidant, anti-inflammatory, and neuroprotective properties. Understanding how different brewing methods influence the abundance of these compounds is critical for maximizing health benefits and aligning coffee consumption with personalized nutrition strategies. This systematic review aims to assess which brewing method, such as drip, French press, cold brew, or regular immersion, results in the highest concentration of caffeine and chlorogenic acids, which provide health benefits. This systematic review follows PRISMA 2020 guidelines. A search of the Scopus, PubMed, and Web of Science databases was conducted, and studies focusing on different Arabica coffee brewing methods and their effects on caffeine and chlorogenic acids were screened. The extracted data include roast level, brewing time, temperature, coffee-to-water ratio, and grind size. Risk of bias was assessed using Risk of Bias in Non-randomized Studies–of Interventions (ROBINS-I). Findings suggest that hot brewing consistently produced higher levels of caffeine and chlorogenic acid than cold brewing. This review has identified brewing methods and parameters that produced the highest caffeine and chlorogenic acids. This research contributes to the growing field of precision functional foods, in which dietary components are customized for individual health benefits, offering a novel approach to dietary personalization that extends beyond standard nutritional recommendations.