 Hello, I'm Claudia Hammond and I'll be here in a moment with the evidence and with a live audience at Wellcome Collection in London where we'll be discussing salt and what it does to the body for good and if we eat too much of it, for ill. When you have a lot of salt, within the blood vessels there will be a lot of sodium, it will attract water and that leads to high blood pressure. When someone has high blood pressure, it can lead to heart attacks.