Dr Chris van Tulleken follows the extraordinary journey food takes through our bodies – from the very first moment we see and smell a potential meal... until it finally emerges at the other end of our digestive tract. Be prepared for plenty of gross moments in this one-hour lecture!

In this lecture, Dr Chris van Tulleken investigates how we get energy from our food and how what we eat makes us who we are. He reveals how combustion engines get their energy in a series of controlled explosions – which he demonstrates using a kitchen cupboard of different foods. As the bangs get bigger, it becomes clear that our bodies can’t get their energy in the same way. Luckily, Chris shows us our bodies are much cleverer than even the most advanced engine.

What did the very first meal on earth look like? To begin his third and final Christmas Lecture in an explosive fashion, Dr Chris van Tulleken takes us back more than four billion years, to the beginnings of life. This was when microscopic bugs first began eating gases and metal, marking the start of an incredible food web which, billions of years later, humans have learned to master.