The researchers – at King’s and the University of North Carolina at Chapel Hill – say anorexia should now be considered a “metabo-psychiatric disorder” as it is a disease of mind and body.
How does metabolism affect the risk of anorexia?
The researchers have not fully explored the role played by the genetic instructions they discovered.
However, they suspect the mutations allow people to starve their bodies for longer.
When most people lose weight, there are signals in the body that push back, stimulating the appetite..
“These are very important in controlling the set-point of weight,” Prof Treasure told BBC News.
“It’s possible that when people lose weight with anorexia nervosa, they haven’t got such strong drivers getting the set-point back to normal.”
How important are these findings?
“It’s very significant because there’s been difficulty knowing what sort of disorder anorexia is,” Prof Treasure told BBC News.
“There have been swings in our understanding
“Now, we know it’s a complex mixture of aspects from the body and the mind that interact and cause this complex disorder.”
Knowing anorexia was a mix of the physical and the mental could persuade patients to have treatment, she added.
What do the experts say?
Andrew Radford, the chief executive of Beat, said: “This is groundbreaking research that significantly increases our understanding of the genetic origins of this serious illness.
“We strongly encourage researchers to examine the results of this study and consider how it can contribute to the development of new treatments so we can end the pain and suffering of eating disorders.”