It's official. The world is getting noiser. Silence is disappearing, increasing stress, raising blood pressure, having a bearing on cardiovascular disease, dementia, diabetes, and of course, hearing loss. The World Health Organisation says this comes at a cost of one million healthy life years every year in Europe alone, with 20% of Europeans claiming to be suffering physically because of noise. Science writer Kayt Sukel joins us to talk about the need for quiet in our louder lives now, and how much quiet we need for our sanity.