Night eating syndrome was first identified at the University of Pennsylvania in 1955. It’s estimated that between 1% and 6% of adults struggle with night eating syndrome (NES). Night eating syndrome is included in the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders), listed under “Other Specified Feeding and Eating Disorders”. NES generally makes its first appearance during a person’s late teens to late 20-something years.
For people who have NES, 25% or more of their daily food intake occurs after dinner time and often continues throughout the night. Night eating syndrome can affect a person’s overall health and wellness. It can contribute to or exacerbate weight gain, obesity, blood pressure and blood sugar issues as well as mental health and general well being.
NES is most commonly found throughout the obese population, affecting anywhere from 10-25% of people who are obese. It is also found disproportionally among people who suffer from a certain type of depression, from anxiety and feeding disorders, addictions and those who have other delayed circadian rhythm syndromes. It is equally found among men and women.
In addition to other health problems, NES contributes to sleep disorders and sleep deprivation. It is a serious problem for those who suffer with it. Fortunately, there are treatments and therapies that can help to reduce its symptoms.
As with other sleep and food disorders, as well as many other complex health issues, symptoms can be confusing or even misleading. Self-diagnosing and self-medicating can often lead to bigger problems. If you find that the below symptoms are familiar to you, speak with your doctor. He or she can identify or rule out other health issues, and help to design a treatment program for NES.
To be symptomatic of NES, symptoms must occur on a regular basis (2-3 times per week or more). Occasional snacks at night are generally not symptomatic of NES. Temporary changes in schedules or routines that delay eating are also not symptomatic of NES; however, if prolonged, these scheduling behaviors can make a person more at risk for developing NES.
The cause (or causes) of night eating syndrome are still being studied, along with NES’ interrelationships with obesity, mental illness, sleep disorders and addiction. There are a few prevalent theories that are being strongly looked at.
After years of study, it seems likely that night eating syndrome is a circadian rhythm disorder, or the result of one. It presents a similar pattern to a circadian rhythm disorder known as delayed sleep disorder. Delayed sleep disorder is caused by a delay in the circadian rhythm that controls when a body is ready for sleep and when it feels awake. These daily occurrences are both pushed forward several hours. People who have delayed sleep disorder are generally wide-awake through much of the night, not feeling the need for sleep until 2 or 3 a.m., or later. Similarly, they don’t feel awake until very late in the morning or early in the afternoon. Night eating syndrome behaves similarly.
That being said, there is also no officially designated cause of circadian rhythm disorders. However, it’s strongly believed that genetic dispositions play a role. Hormone secretions are being studied. Behavior patterns that trigger and/or reinforce circadian rhythm disorders are being studied as well. Therefore, NES’ causes, symptoms, and treatments represent a broad range of medical and psychological study.
Circadian rhythm disorders are often found comorbidly with a number of other illnesses. In some cases, there may be cause-effect relationships between them; in other cases, they may have no direct causal relationships. More about NES’ comorbidities are discussed below.
One interesting indicator that may help in studying NES is that it is often found in people who suffer from a specific, and less common, type of depression – one that is more pronounced at night. Generally, depression is worse in the early part of the day than it is in the evening. This more common type of depression isn’t generally found as being comorbid with night eating syndrome.
Other possible causes that are being studied in terms of NES include sleep apnea and restless leg syndrome (RLS). Self-medicating with food for stress and night time depression may also be contributing factors in the cause of night eating syndrome. This is partly evident in the fact that a lot of NES eating consists of carbohydrate-rich foods.
Behavioral factors that seem to trigger or contribute to NES generally begin with scheduling issues. Late night study or work sessions that occur on a regular basis, the pressure or desire to work through breakfast or lunch, skipping food during the day in the interest of dieting and then making up for caloric intake in private at night, can all set up patterns that may lead to developing NES.
Much research is being done as to the genetic causes of circadian rhythm disorders and it seems clear that there are genetic dispositions to delayed sleep and eating cycles. Behavioral issues, however, can compound them. Retraining sleep and eating behaviors can also lead to effective treatment.
Just as specific medical causes haven’t been confirmed for NES, there is also no specific medication that will cure night eating syndrome. A great amount of success has resulted from behavioral therapy (sometimes combined with traditional talk therapy) along with the treatment of symptoms. If you’re diagnosed with NES, your doctor, psychologist, sleep specialist and/or dietician/nutritionist will likely prescribe treatments, or combinations of treatments.
Due to a lack of certainty as to the cause(s) of night eating syndrome, it is hard to identify a way to prevent it. However, in the section below, a number of comorbid and complicating health issues are discussed. It’s possible that treatment of these issues can help to prevent the onset of or lessen the intensity of NES.
Before being treated for NES, you must be diagnosed. This process starts by meeting with your doctor and having a full physical exam as well as a conversation about sleep and eating habits. In addition, you may be asked to keep a sleep and food journal for a few weeks, followed by returning for continued evaluation. If you exhibit combinations of the above symptoms, you will also likely be referred for a psychological intake and/or a sleep study. As NES is a complicated disorder, its diagnosis can be complicated as well.
Your doctor will also identify and/or rule out related or comorbid disorders.
Comorbid illnesses are ones that are present along with, but are usually not directly part of, another illness. NES can be confused or comorbid with many things. It is often confused, and sometimes found along with, SRED (sleep related eating disorder) or BED (binge eating disorder). However, these are all separate disorders.
In addition, addiction, anxiety disorders, night time depression, ADHD, delayed sleep disorder, other eating disorders, obesity, dieting, poor quality sleep or food absorption, a history of self-injuring, diabetes and metabolic syndrome may have either comorbid or cause-effect relationships to NES.
As you can see, night eating syndrome is quite complex and challenging to treat. But, through knowledge, you can find resources for treatment and relief. You can also rest assured that you are not alone in your struggle and that there are medical and science professionals who are dedicated to unraveling its mystique.