Chocolate has been consumed as confection, aphrodisiac, and folk medicine for many years before science proved its potential health benefiting effects. Main compounds of cocoa and chocolate which contribute to human health are polyphenols that act as antioxidants and have potential anti-inflammatory, cardioprotective, antihepatotoxic, antibacterial, antiviral, antiallergenic, and anticarcinogenic properties. This paper gives a short overview of scientific literature regarding cocoa polyphenols and influence of cocoa and chocolate on human health. Although research on health benefits of dark chocolate and cocoa is quite extensive nowadays and shows potentially beneficial effects of dark chocolate and cocoa, there are still lots of unknowns and some controversies. This is obviously an area that needs more research in order to determine factual influence of chocolate on health. 1. Introduction Cocoa and chocolate are consumed by humans for thousands of years. To Mayan people, cocoa pods were symbols of fertility and life and food of gods. Aztecs believed that consumption of cocoa gave wisdom and power and used cocoa as currency. Aztecs and Mayas made dark, unsweetened drink based on cocoa, which was called xocoatl. They seasoned it with chili peppers and added corn meal, but sugar was unknown to them. In 1492 Columbus brought cocoa beans from America to Europe, but at that time they were not interesting to Europeans [1]. Hernan Cortez, in 1528, brought cocoa to Spain along with secret of making Chocolatl. In Spain, sugar, vanilla, nutmeg, cloves, allspice, and cinnamon were added to the original recipe and aphrodisiac shortly made breakthrough in Europe [1]. However, chocolate bars were not produced until the 18th century, when mechanical mills for squeezing cocoa butter from cocoa mass were produced, and milk chocolate was first produced in the 19th century by Daniel Peter and Henry Nestle. Rodolphe Lindt invented a process called conching, which enabled formation of smooth chocolate aroma and Milton Hershey was a pioneer of mass production of affordable chocolate bars. For many years, chocolate was consumed purely for pleasure, but in the last 20 years researches have shown that dark chocolate and cocoa could have beneficial effect on human health due to high content of polyphenols. Polyphenols are large and heterogeneous group of biologically active secondary metabolites in plants, where they act as cell wall support materials, colourful attractants for birds and insects, and defence mechanisms under different environmental stress conditions (wounding,
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