The doctor and broadcaster, Chris van Tulleken, on why ultra-processed food is making us fat and ill, the team that think they're close to cracking the male contraceptive pill, and the WHO's drive to get more people vaccinated. Like this podcast? Please help us by <a href="https://www.thenakedscientists.com/donate">supporting the Naked Scientists</a>

Did rugby give me dementia at 40?

The Naked Scientists flagship science show brings you a lighthearted look at the latest scientific breakthroughs, interviews with the world's top scientists, answers to your science questions and science experiments to try at home.