ntermittent fasting is a relatively popular diet regimen involving periods of fasting and eating. Some people fast for a certain window each day while others may fast for several days at a time. Although many people who follow this eating approach tout benefits such as weight loss, fat loss, and lower cholesterol, others are skeptical and are concerned that it may mimic disordered eating symptoms or lead to an eating disorder. (1)
Further any form of physical deprivation tied to body image can be an indication of a vulnerability to eating disorders, and therefore extreme concern about this widely popular intervention is of great concern.
What is Intermittent Fasting?
Intermittent fasting (IF) is a pattern of eating that involves cycling between periods of fasting and unrestricted eating, and it occurs on regular, scheduled intervals. People typically engage in intermittent fasting in order to lose or manage their weight.
Is Intermittent Fasting Good For You?
Intermittent fasting has been touted to be healthy for your body, even by medical experts. However, the concept of “the road to hell is paved with good intentions” is worthy of consideration when it comes to intermittent fasting.
Below is just a short list of the harmful impact of intermittent fasting (there are myriad other medical conditions):
- Slowed metabolism
- Disregard of metabolic needs of the body
- Dysregulation in the ability to manage hunger
- Excessive weight loss, which can impair the immune system
- Impairment in hematological function
- Decrease in energy levels and poor concentration
Additionally, severely limiting calories can be harmful to people with certain medical conditions like diabetes. Likewise, individuals who take medications for heart disease or blood pressure may experience fluctuations or imbalances of potassium, sodium, and other vital minerals. (2)
Intermittent fasting may also cause individuals to overeat during their designated eating periods, which may result in weight gain instead of weight loss—not to mention the fact that this pattern constitutes disordered eating behaviors, and eating disorder behaviors such as restriction and binging. (2)
Intermittent Fasting vs. Disordered Eating
The most common eating disorders include atypical anorexia nervosa and binge eating disorder, although there are many others. (3) Eating disorders have a strict set of criteria individuals must meet in order to be diagnosed with these conditions. However, while many people may not have a full-blown eating disorder, they may exhibit unhealthy eating, known as disordered eating.
Disordered eating typically refers to maladaptive eating behaviors that don’t yet fit the criteria for an eating disorder but may lead to the development of a clinical eating disorder. People may be struggling with disordered eating if they eat for a reason other than hunger and nourishment and/or they are restrictive in their eating patterns, denying to meet their body’s needs based on internal signals of hunger and satiety.
People with disordered eating may skip meals, eat in a dysregulated manner or be more likely to eat when they experience a negative emotion, eating as a way to cope with painful emotions. This is oftentimes associated with a restrictive mindset as the person is prone to under-eating and missing meals or needed snacks at other times of the day. Additional signs include engaging in binging or purging behaviors, or avoiding eating major food groups. (4)
Other signs of of disordered eating behaviors may include:
- Restrictive eating
- History of weight cycling
- Binging and purging
- Recurrent dieting
- Laxative misuse and abuse
- Eating in response to strong emotions (often associated with restrictive mindset)
- Lack of connection to hunger and fullness cues
- Mindset of mistrust of body
- Excessive focus on body size and shape
Some experts believe that intermittent fasting, by definition, is a pattern of disordered or unhealthy eating, due to its restrictive nature and rigid schedule. Likewise, others are concerned that intermittent fasting may promote binging, erratic eating patterns, and a depressed mood. (5) In any event, intermittent fasting is associated with intentional restriction and overriding hunger cues, which is a hallmark of disordered eating and eating disorders. Intermittent fasting is therefore considered by many to be a highly dangerous “gateway” behavior placing an individual at risk for the development of eating disorders.
Intermittent Fasting as a Risk Factor for an Eating Disorder
Despite the controversy surrounding intermittent fasting and its potential unhealthy eating patterns, one thing has been found to be true: intermittent fasting is a risk factor for maladaptive eating behaviors and eating disorders. (6,7)
Specifically, fasting has been found to increase the risk of developing bulimia nervosa or binge eating disorder. Some studies have found that caloric restriction, such as during intermittent fasting, may increase the rewarding value of food, which may explain why fasting increases the likelihood of binge eating. Likewise, fasting can deplete tryptophan, a precursor of serotonin. Lower serotonin levels may increase the risk of binge-eating high-carbohydrate food in an attempt to restore these levels. (7)
Others are at risk for development of symptoms more consistent with anorexia nervosa.
In any event, the act of restriction of calories leaves the body underfed, and depending on the individual can lead toward the path of further distance from internal regulation, or the act of responding to their body’s need to eat based on biologically based cues of hunger and satiety.
When is Fasting a Symptom of Disordered Eating?
Not everyone who engages in intermittent fasting meets the criteria for an eating disorder, but there are some indicators that someone’s fasting has progressed to a problematic and potentially dangerous pattern of behaviors. These may include: (3,8)
- Obsessing with losing weight
- An intense fear of gaining weight
- A distorted body image
- Self-esteem that’s heavily dependent on body shape and weight
- Feeling ashamed, guilty, or distressed after eating
- Eating alone to avoid embarrassment
- Being preoccupied with calories, fat grams, carbohydrates, weight, and more
- Cutting out entire food groups, such as carbohydrates
- Isolating from loved ones
- Frequently checking in the mirror and/or difficulty engaging in social experiences due to body checking, or body checking in general
- Experiencing unpredictable mood changes
- Over-exercising, exercising to compensate for eating, exercising despite recommendations to rest, being unable to take rest days, and/or missing out on important aspects of social life due to drive to exercise
Many of these signs are emotional or psychological in nature, and that’s frequently what separates intermittent fasting from disordered eating. Moreover, it’s important to consider how a person may feel if they ate during their designated fasting time. If they would feel ashamed or view themselves as a failure, this is a sign that their intermittent fasting has become unhealthy.
If you or someone you care about are struggling with disordered eating, including dieting, or living with a restrictive mindset, Within Health is here to support you. Our innovative treatment modalities include attuned, inclusive care options for every body type. Call our clinical care team now to learn about our first-steps in establishing a healthy relationship between your body and food.
- Harvard School of Public Health. (n.d.). Diet Review: Intermittent Fasting for Weight Loss.
- Harvard Health Publishing Harvard Medical School. (2020). 4 intermittent fasting side effects to watch out for.
- National Institute on Mental Health. (2016). Eating Disorders.
- Pennesi, J. & Wade, T.D. (2016). A systematic review of the existing models of disordered eating: Do they inform the development of effective interventions? Clinical Psychology Review 43: 175-192.
- Harvie, M., & Howell, A. (2017). Potential Benefits and Harms of Intermittent Energy Restriction and Intermittent Fasting Amongst Obese, Overweight and Normal Weight Subjects-A Narrative Review of Human and Animal Evidence. Behavioral sciences (Basel, Switzerland), 7(1), 4.
- Golden, N.H., Schneider, M., Wood, C. (2016). Preventing Obesity and Eating Disorders in Adolescents. American Academy of Pediatrics 138(3).
- Stice, E., Davis, K., Miller, N. P., & Marti, C. N. (2008). Fasting increases risk for onset of binge eating and bulimic pathology: a 5-year prospective study. Journal of abnormal psychology, 117(4), 941–946.
- National Eating Disorders Association. (n.d.) Warning Signs and Symptoms.