Late night eating and midnight snacks may not seem like a likely cause of health problems but can have various adverse effects on the body and sleep. There has been some debate over the link between late night eating and weight gain. However, even beyond weight gain there is sufficient evidence to suggest that late night eating and midnight snacks should be avoided.
What is Late Night Eating?
Late night eating is broad term to describe eating after dinner, before bedtime and even awaking at night to eat. It is not uncommon for most of us to indulge in this behavior occasionally. This is usually not a cause for concern, especially when it occurs as a result of being awake at night due to work or social activities. However, for some people this late night eating is a daily occurrence and has a host of effects on nutrition, sleep and even health.
Should we eat at night?
Appetite ensures that food is consumed at regular intervals to maintain a constant supply of energy to the body. The concept of three square meals daily is outdated and it is now accepted that smaller meals more frequently is a better approach. Collectively, a person should not exceed the optimal calorie intake for their specific metabolic demands irrespective of the time of eating or number of meals daily. This will help prevent weight gain which is a growing problem globally.
Late night eating should be avoided for obvious reason. The body is soon to enter a low energy state (sleep) and there is no immediate or short term demand for significant energy. In addition, eating late at night can cause other adverse effects such as sleeping problems, aggravate conditions like gastroesophageal reflux disease (GERD or acid reflux) and may even trigger night sweats (1).
The only exception is when a person is active at night as a result of night shift working and instead sleeps during the daytime. Therefore the focus should not be on nighttime eating but instead on eating immediately before sleep and in-between sleep. This may also be relevant to daytime napping which is a habit for some people. Eating immediately before a nap may have some of the same effects as eating before a full night’s sleep.
Read more about overeating.
Causes for Eating at Night
There are several reasons why people choose to eat late at night or may feel compelled to eat. Sometimes there is a sensation of hunger that needs to be satisfied while at other times there is no hunger sensation despite the desire to eat. The exact cause should be diagnosed by a medical professional. Some of the more common causes of eating at night are discussed below.
Upper Digestive Tract Problems
Gastritis and peptic ulcers are two common conditions that causes a discomfort or pain in the stomach which may be mistaken for hunger. This ranges from a dull gnawing ache to a sharp burning pain. Sometimes foods temporarily eases this discomfort only for it to return a short while thereafter. Similarly there may be temporarily relief of heartburn in acid reflux as a result of eating, specifically when consuming alkaline foods or drinks like milk.
Read more about heartburn and sleeping problems.
Intoxication and Substances
Various substances can increase appetite due to activity on the appetite centers, altering blood sugar levels or aggravating pre-existing upper digestive tract problems. Alcohol and marijuna are two substances that are used for non-therapeutic purposes which stimulates appetite. Alcohol also aggravates gastritis and peptic ulcers. Other illicit substances may have a similar effect.
Boredom and Habit
Bordeom is another common reason why many people eat after meals and before bedtime. The duration between dinner and bedtime may be the period when many people feel bored and turn to eating. In addition, this may become a habit and there is a compulsion to eat during this period. In both cases, it is a behavioral issue rather that being associated with hunger, discomfort or pain.
Problems falling asleep or remaining asleep for sufficient periods of time are other common causes of late night eating and midnight snacking. A person may feel the need to have a ‘full stomach’ in order to sleep or use food as a means to relax and assist with falling asleep.
Similarly a person may awake after a short period of sleep and feel the need to eat in order to return to sleep. Stomach conditions like gastritis tend to worsen in the early hours of the morning due to increased gastric acid secretion. A person may eat to ease the stomach discomfort in order to return to sleep.
Night Eating Syndrome
Night eating syndrome (NES) is a condition where there is nighttime overeating and problems with sleep. People with NES tend to eat excessively between dinner and bedtime, experience insomnia on most nights of the week and tend to have a lack of appetite in the morning.
The exact cause of this syndrome is unclear but appears to be a problem with hormones and the sleep-wake cycle. It is more likely to affect obese people, as well as people with a history of depression, anxiety and substance abuse. There also appears to be a genetic link.
Mental Health Conditions
Irregular eating habits such as late night eating and mid-sleep snacking are commonly observed symptoms with depression, anxiety and psychological stress. It may also be associated with other mental health conditions. The exact reason for this irregular eating habits is not always clear. In many instances, eating and certain foods in particular may help cope with mental health symptoms and is also referred to as ‘comfort eating’.
Eating disorders may be one of the obvious causes of late night snacking and awaking to eat at night. Binge eating disorder and bulimia nervosa may be two eating disorders where this type of eating behavior may be observed. Binge eating disorder is now considered to be the most common disorder in the United States. Therefore the underlying eating disorder needs to be treated in order to stop the abnormal late night eating habits.