The quest to live longer has been one of humanities oldest dreams, but while scientists have been searching, a few isolated communities have stumbled across the answer. On the remote Japanese island of Okinawa, In the Californian town of Loma Linda and in the mountains of Sardinia people live longer than anywhere else on earth. In these unique communities a group of scientists have dedicated their lives to trying to uncover their secrets. Horizon takes a trip around the globe to meet the people who can show us all how to live longer, healthier lives.

Around the world, obesity levels are rising. More people are now overweight than undernourished. Jacques Peretti traces those responsible for revolutionising our eating habits

Around the world, obesity levels are rising. More people are now overweight than undernourished. Two thirds of British adults are overweight and one in four of us is classified as obese.

Jacques Peretti investigates how the concept of 'supersizing' changed our eating habits forever. How did we - once a nation of moderate eaters - start to want more?

Jacques Peretti examines assumptions about what is and is not healthy. He also looks at how product marketing can seduce consumers into buying supposed 'healthy foods' such as muesli and juices, both of which can be high in sugar.