a collection of studies published in a special theme issue of the american journal of preventive medicine has demonstrated the potential of lifelogs captured through wearable cameras from a number of viewpoints. in particular, it has been shown that used as a tool for understanding and tracking lifestyle behaviour, lifelogs would enable the prevention of noncommunicable diseases associated to unhealthy trends and risky profiles (such as obesity, depression, etc.). in addition, used as a tool of re-memory cognitive training, lifelogs would enable the prevention of cognitive and functional decline in elderly people.