Cavemen and women had better sex than modern humans.
New research has found that Brits who switched from a traditional diet to the 'paleo' diet - also known as the caveman or Stone Age diet - saw a huge surge in their libido.
The paleo diet was common thousands of years ago and includes foods such as berries, seeds, veg, fish, fruit, eggs and meats such as rabbit, quail and deer.
A 2,000-strong poll conducted by the recipe box firm Green Chef reported a 48 per cent rise in a person's "active" love life after changing diets.
Richard Butterman switched to a paleo diet last year and has noticed an "obvious increase" in his sex drive.
The 44-year-old said: "I decided to lose weight, but liked the idea of eating like a caveman. After less than a month I noticed I was definitely more interested in my wife."