Flavan-3-ols, commonly known as flavans, are a class of polyphenolic compounds widely found in plants and have significant health benefits due to their antioxidant properties. These compounds play an essential role in the prevention of chronic diseases such as cardiovascular disorders and certain types of cancer. Flavans are structurally diverse and include various subclasses like flavan-3-ols (e.g., catechins) and flavan-4-ols. In terms of applications, flavans are extensively used in food products for their natural flavoring properties, while in pharmaceuticals, they are recognized for their potential therapeutic effects. Research continues to explore the precise mechanisms through which these compounds exert their beneficial actions, making them a promising area of study in nutritional and medical science.