Bulimia rewires the brain to make sufferers see food as an escape from their torment

Women with bulimia nervosa respond differently under stress to food than women without the disorder, a new study revealed. 

In a recent study by the American Psychological Association, women with bulimia were found to have lower blood flow to a part of the brain associated with self-reflection when they are stressed, as compared with increased blood flow in women without the disorder.

The results suggest that women with bulimia nervosa may use food to avoid negative thoughts about themselves, the research team found. 

It also shows that individuals with the eating disorder have a part of their brain that functions differently, causing them to see food as a distraction when they are feeling a high level of stress.

Bulimia nervosa is an eating disorder characterized by a cycle of binge-eating and behaviors such as self-induced vomiting to undo the effects of food and prevent weight gain. 

Stress is considered to be a trigger for binge-eating in patients with the disorder, but there is little research on how those individuals respond to food cues. 

The researchers found that in women with bulimia, the part of the brain associated with self-reflection becomes less active when they are feeling stressed.

The experiment consisted of two studies, and in the first 10 with the disorder and 10 without, all came into a lab to eat a meal.

They then entered an MRI scanner and were shown neutral images of things like leaves and furniture, followed by a series of photos of high fat and high sugar foods. 

Each participant was then given an impossible math problem to solve, which was designed to induce stress and threaten their ego.

The women then reentered the scanner and saw new photos of high fat and high sugar foods, and then rated their levels of stress and food cravings. 

'We found that everyone experienced increased stress after the stress task, and that everyone reported that stress went down after seeing the food cues again,' said co-author Sarah Fischer, PhD, of George Mason University in Virginia.

'Also, every time that participants saw the food cues, they reported that their craving for food went up,' she explained. 

Though patterns of self-reported results were similar for both groups, they had different brain responses as shown by the MRI scans. 

In women with bulimia, blood flow to a region called the precuneus, which is associated with self-reflection, decreased when they were shown images of food. For women without the disorder, blood flow to the region increased.

To examine whether the findings could be replicated in a different sample of women, researchers conducted a second study in which they asked 17 women with bulimia to complete the same tasks. 

'Our results were the same in the second study,' Dr Fischer said. 

'Women reported increases in stress following the stress task and increases in food craving after seeing the food cues. More important, blood flow to the same region, the precuneus, decreased when viewing food cues following stress.'

Lead author Brittany Collins, PhD, of the Children's National Medical Center in Washington, DC, said she believes the decreased blood flow suggests the introduction of food shuts down self-criticism in women with bulimia.

The food images gave these women something to focus on other than negative thoughts about themselves that might have been brought on by stress.

'Our findings are consistent with the characterization of binge-eating as an escape from self-awareness and support the emotion regulation theories that suggest women with bulimia shift away from self-awareness because of negative thoughts regarding this performance or social comparisons and shift focus to a more concrete stimulus, such as food,' Dr Collins explained. 

The results also suggest that there is a neurobiological basis for the use of food to distract individuals when they are feeling high levels of stress. 

'This isn't a highly studied part of the brain, but it gives some scientific hope that there is something biological in women and men that might be linked to the onset of bulimia nervosa,' Patricia Allen, nurse practitioner and the Executive Director of Nursing Services for Summit Behavioral Health in New Jersey told DailyMail.com.

'It's an important finding and helps to show that it is a disease and not a choice, which is key to reducing stigma and judgment,' she explained.   

The study, published in the Journal of Abnormal Psychology, comes as Netflix prepares to release it's new television series To The Bone, which features a 20-year-old character named Ellen who struggles with anorexia nervosa.

Ellen is played by British actress Lily Collins, who has spoken candidly about her own battle with bulimia nervosa as a teenager. 

Speaking recently about the role, the 28-year-old actress said that it was a risk to remind herself of her own traumatic experience. 

In a chapter of her memoir, Unfiltered, Collins recalled how she gorged on 'every type of junk food possible,' later forcing herself to throw up, causing her hair to fall out and her nails to become brittle. 

Even after the extreme effects of the eating disorder began to show, the daughter of Phil Collins continued to starve herself and exercise excessively. 

Collins has since overcome her disorder, and has said the role was one of the hardest she's had to take on in her career as an actress. 

'I hope that by casting a little light into the darkness of this disease we can achieve greater understanding and guide people to help if they need it,' she said. 

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