There has been a flurry of interest in functional foods over the past few months. Health claims range from lowering cholesterol to improving vitality. Functional foods have been popular in the Far East for many years but only arrived in the UK six years ago. They are now the most rapidly growing sector of the food industry, with estimates suggesting we currently spend around £1 million on them every day. To make informed choices, consumers and health professionals need to know the truth behind the hype. In this article we review the range of functional foods now available, take a look at the evidence for their claims and explore the pros and cons of using them.