There's a reason we find it hard to resist cupcakes, a bacon sandwich or wedge of Camembert. And it's not just the smell or the taste.
Scientists say we are subconsciously drawn to unhealthy food because we see it as dangerous and attractive. It's the same lure that makes "dangerous" people irresistible - and the more danger we sense, the harder it is to ignore.
Researchers asked people to draw a line between two dots on a computer tablet and answer questions about pictures of food, including bananas and pizza, that appeared on the screen.
Most people unconsciously bent their lines towards the image. And the strongest pull of all was felt towards unhealthy food that the subjects saw in a negative light.
Francesco Foroni, lead researcher on the study at Italy's International School for Advanced Studies, says our brains are hardwired to pay attention to dangerous things and the test results explain why so many diets fail - we simply cannot resist the things we should shun the most.