<div>Why might your lemon not be vegan? How does a lemon affect your empathy? Who used lemons as a contraceptive?</div>

15: Onions

From the makers of QI and No Such Thing As A Fish: Gastronomically-minded QI researchers Jack Chambers and Manu Henriot join chef and food writer Rosie MacKean to unpack the world of food and drink, one lunchbox at a time.

Can you unboil an egg? Why would you milk a spider?  How much Dairy Milk would it take to kill you? Dig in now to get answers to the questions you never knew you had.