Boris Nemzer, Fadwa Al-Taher, Nebiyu Abshiru, Elvira González de Mejı́a
Coffee contains various bioactive compounds with potential benefits for human health. Coffee has been shown to, and may, display neuroprotective properties, potentially preventing the onset of neurodegenerative conditions such as Alzheimer's and Parkinson's diseases. Coffee by-products (pulp/husks, silverskin, and spent coffee grounds) exhibit similar phytochemistry and health benefits to coffee. They are also rich in dietary fiber, carbohydrates, phenolic compounds, and caffeine, which vary depending on the beverage processing, roasting, and preparation methods. Coffee and coffee industry by-products are sources of unique functional ingredients that affect gut microbiota. This review aims to summarize the phytochemical and nutritional composition of whole coffee cherries, coffee beans, and coffee by-products as well as their bioavailability, bioactivity, and multifunctionality in supporting human wellness, neuroprotection, and metabolic health. The bioactive compounds of coffee and its by-products suggest their unique applicability as functional food beverages, dietary ingredients, and health supplements.