Oxytocin, or love hormone, could be used as a treatment for the eating disorder anorexia nervosa, scientists suggest.
Small studies by British and Korean scientists indicated patients were less likely to fixate on food and body image after a dose of oxytocin.
Oxytocin is a hormone released naturally during bonding, childbirth and breastfeeding.
It has already been suggested as a treatment for a range of psychiatric disorders, and has been shown to help lower social anxiety in people with autism.
One four-week study in Australia found people given doses of oxytocin had reduced weight and shape concerns.
In the first of the most recent studies, published in Psychoneuroendocrinology, 31 patients with anorexia and 33 people who did not have the condition were given either a dose of oxytocin, delivered via nasal spray, or a placebo, or dummy, treatment.
They then looked at a series of images to do with a range high and low calorie foods and people of different body shapes and weight.
People with anorexia have previously been found to focus for longer on images of overweight people and what they perceive as undesirable body shapes.
However after taking oxytocin, patients with anorexia were less likely to focus on such “negative” images of food and fat body parts.
The second study, published in PLOS ONE, involved the same people and looked at their reactions to facial expressions, such as anger, disgust or happiness.
It has been suggested that anorexia can be linked to a heightened perception of threat, and animal research has shown oxytocin treatment lessened the amount of attention paid to threatening facial expressions.
In this study, patients with anorexia were less likely to focus on the “disgust” faces after oxytocin treatment.
They were also less likely to avoid looking at angry faces.
Eating disorder expert Prof. Janet Treasure, from King’s College London’s Institute of Psychiatry, led both studies.
She said: “This is early stage research with a small number of participants, but it’s hugely exciting to see the potential this treatment could have.
“We need much larger trials, on more diverse populations, before we can start to make a difference to how patients are treated.”
Her co-researcher, Prof. Youl-Ri Kim, from Inje University in Seoul, South Korea, added: “Our research shows that oxytocin reduces patients’ unconscious tendencies to focus on food, body shape, and negative emotions such as disgust.
“There is currently a lack of effective pharmacological treatments for anorexia.
“Our research adds important evidence to the increasing literature on oxytocin treatments for mental illnesses, and hints at the advent of a novel, ground-breaking treatment option for patients with anorexia.”