A "love hormone" may be able to treat those suffering from anorexia nervosa, according to a recent study.

Researchers from King's College London's Institute of Psychiatry and the Inje University in Seoul, South Korea found that oxytocin - a hormone released naturally during bonding, including sex, childbirth and breastfeeding - alters anorexic patients' tendencies to fixate on images of high calorie foods, and larger body shapes.

Anorexia nervosa is one of leading causes of mental health-related deaths, both through physical complications and suicide. As well as problems with food, eating and body shape, patients with anorexia often have social difficulties, including anxiety and hypersensitivity to negative emotions.

"Patients with anorexia have a range of social difficulties which often start in their early teenage years, before the onset of the illness. These social problems, which can result in isolation, may be important in understanding both the onset and maintenance of anorexia," senior author Janet Treasure said in a statement. "By using oxytocin as a potential treatment for anorexia, we are focusing on some of these underlying problems we see in patients."

For the study, 31 patients with anorexia and 33 healthy controls were given either a dose of oxytocin, delivered via nasal spray, or a placebo. The participants were then asked to look at sequences of images relating to food (high and low calorie), body shape (fat and thin), and weight (scales). Once the images flashed on screen, the researchers measured how quickly participants identified the images. If they had a tendency to focus on the negative images, they would identify them more rapidly. The test was done before and after taking oxytocin or placebo.

After taking oxytocin, patients with anorexia reduced their focus (or 'attentional bias') on images of food and fat body parts. The effect of oxytocin was particularly strong in patients with anorexia who had greater communication problems.

"Our research shows that oxytocin reduces patients' unconscious tendencies to focus on food, body shape, and negative emotions such as disgust,"Youl-Ri Kim, lead author of the study, said in a statement.

Kim said there is currently a lack of effective pharmacological treatments for anorexia, and their research could improve that.