Coffee is slightly acidic (pH 5.0–5.1) and can have a stimulating effect on humans because of its caffeine content. Coffee is one of the most popular drinks in the world. It can be prepared and presented in a variety of ways. The effect of coffee on human health has been a subject of many studies; however, results have varied in terms of coffee’s relative benefit.The majority of recent research suggests that moderate coffee consumption is benign or mildly beneficial in healthy adults. However, the diterpenes in coffee may increase the risk of heart disease.