Intermittent fasting (IF) is a popular diet trend among health and fitness enthusiasts, which involves not eating during planned intervals.
While intermittent fasting may offer some health benefits, researchers are still working to understand the full impact of this eating pattern.
A recent study published in Eating Behaviors looked at intermittent fasting among adolescents and young adults in Canada.
The researchers found an association between intermittent fasting and the behaviours and psychopathology of eating disorders and other dangerous behaviours among some members of this age demographic.
The results indicate a need for more research into the potential risks of intermittent fasting.
Benefits and drawbacks of intermittent fasting
Intermittent fasting can take on a few different forms.
A typical example of IF is fasting for two non-consecutive days in the week.
Another method is to eat only during certain times of the day. For example, the 16/8 method involves fasting for 16 hours and eating only during an 8-hour window.
Blanca Garcia, RDN, a Los Angeles-based registered dietitian nutritionist and nutrition specialist with the Measurement Instrument Database for Social Sciences (MIDSS), not involved in the study, noted the potential benefits of eating within specific time frames to Medical News Today:
Some evidence suggests that intermittent fasting can contribute to weight loss and provide specific health benefits.
Intermittent fasting may improve insulin sensitivity and heart health. It may also help prevent disorders like Alzheimer’s disease and cancer.
However, there are potential drawbacks to intermittent fasting.
For instance, intermittent fasting may increase the risk of hypoglycemia and could induce muscle wasting if someone isn’t getting enough protein.
For certain people and groups, like young children and older adults, fasting could be dangerous and should be avoided.
In addition, many aspects of the possible drawbacks of intermittent fasting still haven’t been studied.
Disordered eating and intermittent fasting
For the present study, researchers examined the relationship between intermittent fasting and eating disorders among adolescents and young adults.
This study gathered data from the Canadian Study of Adolescent Health Behaviors.
Researchers included 2,762 adolescents and young adults in their analysis, including women, men, and transgender or gender non-conforming individuals recruited via social media.
Researchers found that intermittent fasting was highly popular in this age demographic.
Study author Kyle T. Ganson, PhD, MSW, assistant professor and Factor-Inwentash Faculty of Social Work with the University of Toronto, Canada, explained to MNT: “IF [Intermittent fasting] was highly common among the sample, including 48% of women, 38% of men, and 52% of transgender/gender non-conforming participants, and participants fasted for, on average, 100 days in the past 12 months.”
Researchers used an eating disorder examination questionnaire to examine behaviours and psychopathology. They wanted to see how these attitudes and patterns were similar to those of people with eating disorders.
The questionnaire examined participants’ dietary restraints and concerns about weight, shape, and eating. They also looked at eating disorder behaviours, like binge eating, compulsive exercise, and laxative use.
“Among all groups (men, women, and transgender individuals), any engagement in intermittent fasting (IF) in the past 12 months was associated with greater eating disorder attitudes and behaviours,” Ganson explained.
“Additionally, among women, in particular, IF was associated with all eating disorder behaviours, including binge eating, vomiting, laxative use, and compulsive exercise, while among men, IF was associated with compulsive exercising.”
The findings indicate a need for further research into the potentially harmful effects of intermittent fasting, particularly among young people.
Study limitations and continued research
While the new research provides insight into some potential dangers of intermittent fasting, it did have several limitations.
First, the study cannot determine whether intermittent fasting causes eating disorders.
In addition, the data collection methods relied heavily on participants’ self-reporting, which can lead to potential errors. And while the sample was diverse, there is still the potential for selection bias based on the methods used.
Participants could also interpret the survey questions differently, increasing the risk of response bias. Finally, the questions may not have captured all eating disorder cognition and behaviours.
All these limitations indicate the need for further research in this area.
Despite these challenges, healthcare professionals can still glean insight. Ganson noted a few clinical implications of the research: “The data from this study indicate that IF may be problematic and associated with severe and harmful eating disorder attitudes and behaviours. Healthcare professionals need to be aware of these potentially correlated behaviours and understand contemporary dietary trends like IF that are commonly discussed among young people, particularly on social media. Thus, more comprehensive assessments need to be conducted among young people related to dietary practices and proper guidance [given] when necessary.”
Engaging safely in intermittent fasting
People in some groups should not engage in intermittent fasting, such aspeople with specific hormonal imbalances.
The results from this study indicate the potential dangers of intermittent fasting among young adults and adolescents.
Still, some people may engage in intermittent fasting safely; by understanding the facts and gathering careful insight from professionals. It’s also important to realise that everyone has different needs and risks.
If you’re interested in trying intermittent fasting, Garcia recommended the following tips to stay healthy:
• Meet with a registered dietitian who can teach you about good food choices.
• Choose a method that gives you nutrition daily.
• Avoid bingeing on high-calorie and fast foods, but incorporate what you like in small doses daily. (e.g., if you like cookies, 1 or 2 cookies daily is OK).
