Night Eating Syndrome
This post was written originally in 2011. At that time both night eating syndrome and binge eating disorder were classified as eating disorders not otherwise specified in DSM. However, since 2011 BED has been entered in the DSM as its own eating disorder and there are two more up-to-date entries here on EDI on that: Binge Eating Disorder One and Two
Judging from the literature on night eating syndrome I would anticipate it will be yet another likely standalone entry whenever the next DSM edition is developed. While I would hope that the fairly compelling evidence that suggests this is a circadian rhythm or sleep disorder (and not an eating disorder) would prevail, I don’t think that it will.
With that in mind, I want to provide the updated information on NES because many, many people with restrictive eating disorders believe that they have night eating syndrome.
The reason that those with either an active long-lived eating disorder or those recently entering a recovery effort will think they have developed night eating syndrome is that they continue to restrict their food intake throughout the day and then find themselves eating what they identify as a “binge” throughout the evening. The core issue for almost everyone that fits this description is they continue to restrict food throughout the day. The cognitive effort to avoid food depletes as the day wears on, and reactive, restorative eating occurs in the evening as a result. This is not NES.
At present NES is defined as consuming 25% of daily intake in the evening, and experiencing nocturnal ingestions.
Those with NES are specifically waking multiple times throughout the night (six to nine times a night) [1] and consuming carbohydrate-laden average amounts of food in what appears to be an unconscious drive to modulate endocrine anomalies such as serotonin, melatonin, leptin and cortisol. The anomalies found with these hormones appear to precipitate insomnia and sleep disruption. They do not eat more than non-restricting controls. Whereas, those with bulimia and BED do. As a reminder, people with BED and BN eat more than non-restricting controls because their bodies are attempting to bring in excess energy to address the damage due to the restriction of intake below what the body requires to sustain its optimal homeodynamic state. Those with NES are not restoring an energy deficit; they have shifted their non-restricting intake into multiple sessions throughout the night.
One of the things that most strikes me reading the published literature on night eating syndrome is how suffused it is with fat panic. It is hard to sift through the cultural noise to arrive at real data points on what actually constitutes night eating as a disorder. Apart from the usual conflating of correlation with causation – namely suggesting that NES causes “obesity” – the definition of NES across the published literature is not displaying strong replication so far and the quality of the studies is poor. The trials are almost all self-report food logs and journals with the rare laboratory short-term study to be found. The subtypes are murky and suffused with crossover issues with other mental disorders. [2] Furthermore, we see yet again the Streetlight Effect, wherein it appears non-fat people have NES endocrine anomalies but they are understudied. If studies select for only BMI>30 subjects then this undermines the framing that NES causes fatness. [3], [4]
First of all, sleep disorders such as narcolepsy and cataplexy are strongly correlated with the presence of night eating syndrome. [5] Additionally, treatment with melatonin agonists appear to help those with NES entrain back to a circadian rhythm that is diurnal for food consumption, lowering the insomnia and nocturnal ingestions. [7],[8],[9]
“Patients with NES appear to have sleep maintenance insomnia ...this disorder reflects a state of internal circadian desynchrony associated with significant sleep complaints.”
Is NES an eating disorder? My interpretation of the literature so far is that it is not. It is a sleep/circadian rhythm disorder of unknown etiology. It has nothing in common with the restrictive eating disorder spectrum that comprises anorexia, bulimia and binge eating disorder along with all the various facets: anorexia athletica, orthorexia, diabulimia, etc. etc.
Can you develop NES with either an active restrictive eating disorder or during an effort to recover from one? I have no idea and there’s nothing definitive in the literature to point to either way. But NES does not involve restriction of intake. So as with a PCOS diagnosis, you should not be assigned a diagnosis of NES unless your restrictive eating disorder is in full remission.
If you are actively in recovery and you find yourself waking in the middle of the night to consume food, then what that signifies is a need to up the daytime calories you consume to support repairs and weight restoration. Remember the guidelines within HDRM are minimum intake amounts and if you treat them as a maximum you will be suppressing a natural extreme hunger that should occur to support repairs. You keep increasing daytime intake until such time as you can sleep through the night. Front load the calories and don’t reinforce the avoidant behaviours that get applied first thing in the morning when cognition is fresh and the threat identification system can ensnare it in delays and avoidance despite the huge energy deficit and drive to survive.
You do not need melatonin agonists to recover from a restrictive eating disorder as it is not a sleep/circadian rhythm disorder. If you have NES, you are not restricting your food intake but you are struggling with how that circadian rhythm shift and insomnia is impacting your day-to-day. If you are reading this and you have NES and either no history of a restrictive eating disorder, or a confirmed history of a restrictive eating disorder that is fully in remission, then speak with your doctor about melatonin agonist support. Or, conversely, discuss the value of full-spectrum light treatment as a non-pharmaceutical intervention. [11]
Birketvedt GS, Florholmen J, Sundsfjord J, Østerud B, Dinges D, Bilker W, Stunkard A. Behavioral and neuroendocrine characteristics of the night-eating syndrome. Jama. 1999 Aug 18;282(7):657-63.
Fortuyn HA, Swinkels S, Buitelaar J, Renier WO, Furer JW, Rijnders CA, Hodiamont PP, Overeem S. High prevalence of eating disorders in narcolepsy with cataplexy: a case-control study. Sleep. 2008 Mar 1;31(3):335-41.
Lundgren JD, Allison KC, O'Reardon JP, Stunkard AJ. A descriptive study of non-obese persons with night eating syndrome and a weight-matched comparison group. Eating Behaviors. 2008 Aug 1;9(3):343-51.
Marshall HM, Allison KC, O'Reardon JP, Birketvedt G, Stunkard AJ. Night eating syndrome among nonobese persons. International Journal of Eating Disorders. 2004 Mar;35(2):217-22.
Fortuyn HA, Swinkels S, Buitelaar J, Renier WO, Furer JW, Rijnders CA, Hodiamont PP, Overeem S. High prevalence of eating disorders in narcolepsy with cataplexy: a case-control study. Sleep. 2008 Mar 1;31(3):335-41.
Echeverri B, Kozak AT, Gildner DJ, Pickett SM. Night eating syndrome subtypes: Differences in binge eating and food addiction symptoms. Eating and Weight Disorders-Studies on Anorexia, Bulimia and Obesity. 2023 Feb 8;28(1):3.
Milano W, De Rosa M, Milano L, Capasso A. Agomelatine efficacy in the night eating syndrome. Case Reports in Medicine. 2013;2013(1):867650.
Milano W, De Rosa M, Milano L, Riccio A, Sanseverino B, Capasso A. Successful treatment with agomelatine in NES: a series of five cases. The Open Neurology Journal. 2013;7:32.
Matsui K, Kuriyama K, Kobayashi M, Inada K, Nishimura K, Inoue Y. The efficacy of add-on ramelteon and subsequent dose reduction in benzodiazepine derivatives/Z-drugs for the treatment of sleep-related eating disorder and night eating syndrome: a retrospective analysis of consecutive patients. Journal of Clinical Sleep Medicine. 2021 Jul 1;17(7):1475-83.
Rogers NL, Dinges DF, Allison KC, Maislin G, Martino N, O'Reardon JP, Stunkard AJ. Assessment of sleep in women with night eating syndrome. Sleep. 2006 Jun 1;29(6):814-9.
Faulkner SM, Bee PE, Meyer N, Dijk DJ, Drake RJ. Light therapies to improve sleep in intrinsic circadian rhythm sleep disorders and neuro-psychiatric illness: A systematic review and meta-analysis. Sleep medicine reviews. 2019 Aug 1;46:108-23.
