Londoners who suffer from seasonal affective disorder, otherwise known as the mid-winter blues, can check out a popular treatment at a new museum cafe.

The Dana Cafe Light Lounge at the Science Museum offers free 20-minute doses of bright light from four light boxes placed around a circular sofa. The light is five times as bright as normal household lighting.

Jennifer Eastwood, a founder of the SAD Association, told the BBC that the light treatment comes from Scandinavia, which has the world's highest known rates of the disorder.

"I'm surprised this has not caught on more in this country," she said.

Scientists believe that 500,000 people in Britain suffer from SAD, the majority of them women. More people have a milder form of the affliction.