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A plate with cutlery placed on a plate to look like a clock with a person holding a fork and spoon on either side of the plate - Is fasting bad for you | dangers of fasting | cutlery implying countdown
December 16, 2021

Is Fasting Bad For You? Why Intermittent Fasting is a Dangerous Fad

Intermittent fasting is a pattern of eating that includes regular periods of fasting. Unlike traditional diets, it does not include any rules on what foods “should” or “should not” be eaten; it specifies when and when not to eat instead. Participants limit their eating to a certain window of time—for example, to just eight hours per day or five days per week—and do not eat for the remainder of the time. 

The trend has become increasingly popular in the last several years for its promises of improved health and weight loss. The more nuanced examination of the potential dangers of intermittent fasting, however, are often not addressed in conversations about the subject. The dangers of fasting may not be readily evident, so in this article, we will cover the potential negative physical and mental side effects, including the dangers for those at risk of or suffering from an eating disorder.

Negative Consequences of Intermittent Fasting

A favorite idea of diet culture is that weight loss is always good because being thin supposedly equals being healthy. We know this is not the case. But with intermittent fasting claiming to improve health as well as promote weight loss, it is not hard to see why diet culture has latched onto it. It is important to understand that diets have an effect on our minds as well as our bodies.

Is fasting bad for you? The following are some of the consequences of intermittent fasting:

  1. Hunger and cravings
  2. Headaches and lightheadedness
  3. Digestive issues
  4. Irritability and other mood changes
  5. Fatigue and low energy
  6. Bad breath
  7. Sleep disturbances
  8. Dehydration
  9. Malnutrition

With this many downsides, the truth of whether fasting is bad for you should be readily apparent.

Research on Intermittent Fasting

You might find yourself thinking, “Not everyone experiences those symptoms” or “Those symptoms are worth it if that means I’ll lose weight.” Despite the promises of weight loss, however, a recent study published in JAMA Internal Medicine showed that “overweight” adults who fasted for 16-hour windows didn’t lose much more weight than the control group that did not fast, and most of the weight they did lose was muscle loss. For many people, long periods without eating can lead them to overeat once the fasting period is over. One can see how this feels very similar to a restrict-binge cycle present in many eating disorders. The combined dangers of fasting with the relatively low chances of the effect you seek means that fasting is detrimental to your health overall in the short-term. 

The evidence of the long-term effectiveness and safety of intermittent fasting is still unknown. Many of the studies that have shown any improvement of certain health issues were done on rats, which limits what we know about the impact of intermittent fasting on humans. The majority of studies involving humans include only small sample sizes tracked over a short span of time. Many report a measurable physiological outcome like short-term weight loss, but they generally ignore any mental and emotional health effects. Several reports do admit that fasting is not for everyone and include a generic recommendation to “check with a professional before starting any diet plan.” The “why” of why intermittent fasting is bad is two-fold, detracting from long-term goals and short-term wellbeing at the same time.

Intermittent Fasting and Eating Disorders

Those who try fasting intermittently may be at greater risk for developing a severe eating disorder. Though eating disorders have no single cause, a key risk factor is dieting. Those who limit their eating to a small window could easily become hard on themselves for breaking their fast “too early” or eating “too late.” Any sort of anxiety or shame surrounding diet can be a warning sign of disordered behavior, which can lead to the development of an eating disorder in those susceptible. Depriving yourself of food for an extended period of time can also increase your stress levels, disrupt your sleep, increase anxiety and depression, and more. 

The trend of intermittent fasting may also be especially harmful for those experiencing or recovering from an eating disorder. Intermittent fasting may hide restrictive behavior and thereby prolong the identification and treatment of a disorder like anorexia, bulimia, or binge eating disorder. It can also make eating disorder recovery much more challenging. Recovery is about reconnecting with your body and learning to tune into natural hunger cues, which is exactly what intermittent fasting asks people to ignore. 

Restrictive eating plans like intermittent fasting can be harmful to one’s mental health as well as one’s physical health. It can also be extra dangerous for those who are at risk of an eating disorder. These things are an essential part of the conversation surrounding intermittent fasting that should not be ignored.

Key Takeaways about Intermittent Fasting

  • Challenging Diet Culture: The narrative that equates thinness with health is pervasive and often misleading. Intermittent fasting, despite its popularity, propagates this idea by promising improvements in health and weight loss, thereby reinforcing harmful diet culture stereotypes.
  • Adverse Effects of Intermittent Fasting: Intermittent fasting can bring about several negative consequences, both physically and mentally. These can range from feelings of hunger and cravings to physical discomforts such as headaches, lightheadedness, digestive problems, mood changes, fatigue, low energy, bad breath, and sleep disturbances. More severe issues may also include dehydration and malnutrition.
  • Potential for Overeating: The study also noted a tendency for participants to overeat after fasting periods. This behavioral pattern mimics the restrict-binge cycle often seen in many eating disorders, raising concerns about the relationship between intermittent fasting and disordered eating habits.
  • Unclear Long-Term Safety and Efficacy: The long-term safety and effectiveness of intermittent fasting remain uncertain. While some studies on rats have shown improvements in certain health issues, these results don’t necessarily translate to humans. Most human studies to date have involved small sample sizes and short durations, often overlooking the mental and emotional health effects, muddying the picture of the combined health impact of intermittent fasting.
  • Increased Risk of Eating Disorders: Intermittent fasting could potentially increase the risk of developing eating disorders. Anxiety or shame related to dieting can indicate disordered behavior, potentially leading to eating disorders in susceptible individuals. For those recovering from an eating disorder, intermittent fasting may also hide restrictive behavior, delay the identification and treatment of the disorder, and complicate recovery efforts.

If you or a loved one is struggling with food or body image and need help, Veritas Collaborative is here for you. Give us a call at 1-855-875-5812 or complete our online contact form