Night eating syndrome (NES) is characterized by a delayed pattern of food intake in which the patients consume at least 25% of their total daily calories after dinner and/or during nocturnal awakenings.
It is still an evolving area of research as to what causes or contributes to NES. Researchers found that depressed patients frequently experience NES, and it is recommended that a depressed patient be evaluated for NES. Some researchers suggest that weight gain, smoking and sleep disturbances are significant risk factors for NES.
Persons diagnosed with NES are more likely to have another eating disorder than members of the general population. From the opposite perspective, NES is more common among persons with eating disorders than in the general population.
It appears that depressed mood and major depressive disorder occur more frequently among persons with NES in comparison to non-NES controls. Associations between NES and a worsening of mood during the latter part of the day, depressive symptoms, and major depressive disorder have also been noted in numerous studies.
NES tends to occur during periods of life event stress. Researchers found that both state and trait anxiety levels among persons with NES were above the normal healthy adult range and perceived stress was at the highest value for that of a healthy community sample.
Over the years, various definitions of NES have been employed. In 2008, experts attending the First International Night Eating Symposium drafted the first consensus driven set of diagnostic criteria for NES:
A. The daily pattern of eating demonstrates a significantly increased intake in the evening and/or nighttime, as manifested by one or both of the following:
At least 25% of food intake is consumed after the evening meal
At least two episodes of nocturnal eating per week
B. Awareness and recall of evening and nocturnal eating episodes are present.
C. The clinical picture is characterized by at least three of the following features:
Lack of desire to eat in the morning and/or breakfast is omitted on four or more mornings per week
Presence of a strong urge to eat between dinner and sleep onset and/or during the night
Sleep onset and/or sleep maintenance insomnia are present four or more nights per week
Presence of a belief that one must eat in order to initiate or return to sleep
Mood is frequently depressed and/or mood worsens in the evening
D. The disorder is associated with significant distress or impairment in functioning.
E. The disordered pattern of eating has been maintained for at least 3 months.
F. The disorder is not secondary to substance abuse or dependence, medical disorder, medication, or another psychiatric disorder.
The Medication Treatment
Relatively little is known about the successful treatment of NES. Limited evidence suggests that serotonergic-based pharmacological treatments may be beneficial.
Although some medications have been shown to be helpful for the treatment of NES, they are not a panacea – the symptoms of NES may not remit or remit fully. Medication is also costly and may produce unwanted side effects, and some people cannot or would prefer not to take medication.
The Psychological Treatment
As an alternative, psychological treatment for NES has been experimented and proved to be effective. Researchers have developed a CBT treatment, which includes the following components:
Night eating syndrome
Retain a food diary and use self-monitoring
Implement a regular eating schedule
Use structured meals and snacks
Establish stimulus/environmental control
Gradually increase morning and decrease evening food intake
Eat the minimum necessary to re-attain evening sleep
Leave bed/bedroom to eat
Use exposure and response prevention for craved foods
Progressive muscle relaxation
Eating and the meaning of food
Sleep and insomnia
Solicitation of social support
Instrumental support in making change
Other than medication and psychological treatment, a unique therapy called bright light therapy (BLT) may also be a viable treatment option.
In a BLT study, participants are given a special light to use in their homes for a certain number of morning sessions, each lasting 60 minutes. Participants need to utilize the light immediately after waking and by 9:00 a.m. and to place the light box on a flat surface at an angle of approximately 30° to their body, with their eyes at mid-fixture level.
Significant reductions were found pre-to-post treatment in night eating symptomatology, mood disturbance, and sleep disturbance. This pilot trial provides preliminary support for the efficacy of BLT for the treatment of night eating syndrome.
Jillon S. Vander Wal. 2012. “Night eating syndrome: A critical review of the literature.” In Clinical Psychology Review, 32, pp. 49-59.
Ashley M. McCune and Jennifer D. Lundgren. 2015. “Bright light therapy for the treatment of night eating syndrome: A pilot study.” In Psychiatry Research, 229, pp. 577-579.
Suat Kucukgoncu, et al. 2014. “Clinical Features of Night Eating Syndrome among Depressed Patients.” In European Eating Disorders Review, 22, pp. 102-108.