In Part one of this two part blog series, we discussed a number of different dietary preferences which are adopted for a range of reasons and how they can be considered restrictive.
In part two, we’re going to delve a little deeper into the potential relationship between diet/ nutrition preferences and eating disorders, in particular when it comes to a plant-based diet.
Types of Eating Disorders
While there are many types of eating disorders and a more in-depth summary of them can be found on our blog here, this piece primarily focuses on the more heavily restrictive types; anorexia nervosa, and orthorexia nervosa, as these are the most thoroughly researched with regards to their correlation with dietary preference:
Anorexia Nervosa – those suffering from anorexia tend to lose a significant amount of weight in a short period of time. There also tend to be a lot of rules involved, for example, only being ‘allowed’ to eat if you’ve undergone excessive exercise or if you’ve lost a certain amount of weight. Regularly checking the body in a mirror or by feel, and obsessive weighing are also common behaviours.
Orthorexia Nervosa – Orthorexia is not a term that is currently recognised by the DSM-V, but involves the unhealthy obsession with eating “pure” or “clean” food.
The issue at hand
As established, there are many overarching benefits to a plant-based diet, whether that be from an environmental, health, or ethical perspective. However, controversy lies within those who adopt such diets due to more deep-rooted, psychiatric issues, such as eating disorders – a speculated means of restricting intake in a socially acceptable way.
Avoiding food because it’s “fattening” or because you’re trying to “be good” evokes more concern than if you are avoiding food because you’re plant-based, and there are no/limited plant-based options available.
While most who follow plant-based diets are able to live happily and without clinically significant weight and shape concerns, the proportion who do present with eating disorders cannot be ignored.
It goes without saying that not everyone that is plant-based is masking an eating disorder, and not everyone that has an eating disorder is plant-based. That being said, there is certainly a correlation, with a 2022 study by Fuller et al., noted that eating disorder clinicians in the UK are, based on their experience, reporting that more of their patients with anorexia nervosa are wanting to follow a vegan diet.
A cross-sectional study among young women in Poland (Gwioździk et al., 2022) found that those following a low FODMAP diet had a higher rate of orthorexia, and therefore a higher rate of restrictive eating than those following a traditional diet.
My Master’s dissertation also researched this exact field – a literature review investigating the association between plant-based diets and the development and maintenance of eating disorders. It looked at 10 studies published in or before 2019, from various countries (United States of America, United Kingdom, Italy, Poland, Turkey), whose study populations totalled over 17000 participants.
- The aims were to determine whether plant-based diets have a higher association with eating disorders than meat-based diets.
- To investigate whether eating disorders manifest as a result of plant-based diets, or whether plant-based diets are resulting behaviours of eating disorders.
- To establish how common plant-based diets are in those that are considered “recovered” from their eating disorder.
The eating disorders found to be most prevalent among plant-based diets were anorexia nervosa, and orthorexia nervosa, with plant-based diets being found to be used as a restrictive tool in those with anorexia, whereas orthorexia and its tendency to only eat “pure” or “clean” foods led more to a plant-based diet.
The review concluded that overall, there appears to be a higher rate of plant-based diets in those who are recovered or are currently suffering from an eating disorder when compared with meat-based diets.
It was also determined motivation for a plant-based diet was prominent, with health-motivated vegetarians and vegans being more at risk of eating disorders than their ethically-motivated counterparts.
Education was also determined as a potential risk factor regarding eating disorders – it was identified that eating disorders and plant-based diets are more prevalent in those that are university-educated, or who come from a more educated background.
Lastly, there was some evidence that plant-based diets are more prevalent in recovered patients than in those with no eating disorder history, but the sample size associated with this finding is too small.
Ultimately, more thorough research into the field needs to be conducted at this stage, but it is certainly good to be aware of the possibility that loved ones may have ulterior motives for suddenly adopting a plant-based diet.
If you are concerned about a friend, Beat have great guidance on how to approach and/or support someone you’re worried about.
References:
Fuller SJ, Brown A, Rowley J, Elliott-Archer J. Veganism and eating disorders: assessment and management considerations. BJPsych Bull. 2022;46(2):116-120. doi:10.1192/bjb.2021.37
Gwioździk W, Krupa-Kotara K, Całyniuk B, Helisz P, Grajek M, Głogowska-Ligus J. Traditional, Vegetarian, or Low FODMAP Diets and Their Relation to Symptoms of Eating Disorders: A Cross-Sectional Study among Young Women in Poland. Nutrients. 2022; 14(19):4125. https://doi.org/10.3390/nu14194125
