Night Eating Syndrome (NES) is a lesser-known eating disorder that impacts approximately 1% of the general population and 6 to 16% of those diagnosed with obesity . The disorder itself is commonly misdiagnosed or misunderstood as Binge Eating Disorder, however, there are important differences between NES and other eating disorders and awareness of these differences is important to proper diagnosis and effective treatment.
Definition of Night Eating Syndrome (NES)
The term Night Eating Syndrome refers to behaviors “characterized by a delayed pattern of food intake in which the patient consumes at least 25% of his or her total daily calories after dinner and/or during nocturnal awakenings .”
NES is not an independent diagnosis in the Diagnostic and Statistical Manual of Mental Illness (DSM-5) but is described in the DSM-5 category OSFED (Other Specified Feeding & Eating Disorders) . The manual specifies that “there is awareness and recall of the eating, “that “the night eating is not better explained by external influences such as changes in the individual’s sleep-wake cycle or by local social norms” and that “the night eating causes significant distress and/or impairment in functioning .”
Professionals aiming to learn more about this disorder held the First International Night Eating Symposium in 2008 and created the following tentative diagnostic criteria for NES:
- 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
- Awareness and recall of evening and nocturnal eating episodes are present.
- 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 is 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.
- The disorder is associated with significant distress or impairment in functioning.
- The disordered pattern of eating has been maintained for at least 3 months.
- The disorder is not secondary to substance abuse or dependence, medical disorder, medication, or another psychiatric disorder .
Interesting Facts About Night Eating Syndrome
While NES is known to eating disorder professionals, research still has a long way to go. There are many theories surrounding the development, prevalence, and cognitions of NES, however, a firm understanding of this disorder has been difficult to ascertain. What research has determined thus far is:
- NES symptoms have been described in psychological literature since approximately 1955.
- NES is more common in patients with other eating disorder diagnoses .
- NES occurs in between 15 to 44% of those diagnosed with Binge Eating Disorder .
- NES occurs in approximately 9 to 47% of patients with Bulimia Nervosa .
- Approximately 12.3% of psychiatric patients meet the criteria for NES .
- 30.6% of those with NES met the criteria for a lifetime substance use disorder .
- Patients with NES are more likely to be prescribed more than one atypical antipsychotic than patients without NES .
- Understand the Risks of Anorexia
- Spot the Signs of Bulimia
- The Causes of Binge Eating Disorder
- Classified Eating Disorders
- Is Diabulimia an Eating Disorder?
- The Health Risks of Orthorexia
What are the Signs of Night Eating Syndrome?
Recognizing NES in a loved one can be difficult, as the behaviors that characterize the disorder occur when most individuals are sleeping. Be aware if your loved one is getting up multiple times throughout the night to snack but recognize that this must occur in conjunction with other behaviors to meet the criteria for NES diagnosis. Some of the additional warning signs mentioned below can help to create a more well-rounded portrait of behaviors.
Physical symptoms of NES can be difficult to detect, however, there are some indicators such as:
- Difficulty falling asleep without eating.
- Depressive symptoms that worsen in evening hours.
- The individual may be overweight or have multiple failed attempts at dieting/weight loss.
Behavioral symptoms of NES are more likely to be noticed during the day than as the behaviors are occurring. Some of these include:
- Lack of appetite in the morning is also referred to as “morning anorexia.”
- Insomnia at least 3 nights per week.
- Increased hunger after dinner and before sleep.
- Reporting beliefs that eating is essential to getting sleep.
- Hiding food.
- Eating to the degree of becoming uncomfortably full.
Night Eating Syndrome Health Risks
Many of the health risks associated with NES are similar to those with BED due to the similarity in behaviors. They can also be related to the physical consequences of obesity due to the increased food intake one engages in. Some of the long-term consequences of NES behaviors include:
- High blood pressure.
- High cholesterol.
- Cardiovascular issues.
- Gastrointestinal issues.
Night Eating Syndrome Causes
There are many theories as to the causes of Night Eating Syndrome behaviors and many of them are accurate. There are numerous biological, psychological, and social factors that contribute to NES development. For example, a key symptom of NES is hyperphagia, which is abnormally increased appetite or consumption of food. This can be caused by injury to the hypothalamus. Additionally, many believe that NES is related to one’s circadian rhythm and the bodily chemicals associated with sleep, pleasure, and hunger.
Many professionals also note that increased stress seems to be associated with NES behaviors. Additionally, NES often co-occurs with eating disorders, anxiety, depressive, and substance use diagnoses.
It is also considered that growing up with a history of trauma or food insecurity can be associated with NES symptoms.
Night Eating Syndrome Treatment Options
There is minimal research on effective treatments for Night Eating Syndrome, however, a few studies have been conducted that indicate pharmacological treatment and Cognitive Behavioral Therapy (CBT) may be promising in reducing NES behaviors . Many researchers have suggested that a combination of the two is most effective. Studies also indicate that mindfulness skills such as progressive muscle relaxation can be helpful .
Regardless of how far research has to go to understand and effectively treat Night Eating Syndrome, the key for those struggling now is to seek support from eating disorder professionals that can adapt effective eating disorder treatments to their NES behaviors.
Do you want to know how treatment can help, read a Case Study on Night Eating Syndrome
-  Kucukgoncu, S. et al (2015). Optimal management of night eating syndrome: challenges and solutions. Neuropsychiatric Disease and Treatments, 11, 751-760.
-  American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.).
-  Allison, K. C. (2010). Proposed diagnostic criteria for night eating syndrome. International Journal of Eating Disorders, 43:3.
-  Lundgren, J.D. (2010). The prevalence of night eating syndrome and binge eating disorder among overweight and obese individuals with mental illness. Psychiatry Research, 175:3.
-  Allison, K. C. et al. (2011). Treatment of night eating syndrome. Psychiatric Clinics of North America, 34:4.
Author: Margot Rittenhouse, MS, LPC, NCC