For years there has been discussion about whether choosing a vegetarian or vegan diet could be linked to a greater risk of developing eating disorders. The hypothesis arises from the fact that those suffering from these pathologies often tend to eliminate entire categories of foods and, in some cases, a meat-free diet can represent a socially accepted way to justify food restrictions.
But is it really like that? A new systematic review with meta-analysis, published in Eating disordersattempted to answer this question by analyzing all available scientific evidence. In an article published on The ConversationBruno Biggiogero Peroni, associated researcher at the Karolinska Institutet, and María Valentina Díaz Goñi, doctoral student at the University of Castilla-La Mancha, illustrated the results of their research, explaining what emerges from the scientific evidence on the possible link between vegetarian and vegan diets and eating disorders.
The study
The research examined 24 studies, for a total of 25,223 participants, comparing people who followed a strict vegetarian or vegan diet with those who consumed meat.
The researchers considered exclusively vegetarians (who exclude meat, poultry, fish and seafood) and vegans (who eliminate all foods of animal origin), excluding more flexible diets such as pescatarian or flexitarian diets.
The included studies used validated questionnaires to assess the presence of typical symptoms of eating disorders, such as food restriction, binge eating, loss of control during meals and strong concern about weight or body shape. However, these are tools that measure the symptoms reported by participants and do not allow a clinical diagnosis to be formulated.
Taken individually, the studies showed very different results. Some reported a greater presence of symptoms between vegetarians and vegans, others even fewer, while several found no difference.
However, when all the data were combined in the meta-analysis, there was no significant overall difference between those following a vegetarian or vegan diet and those consuming meat.
This means that choosing to eliminate meat or animal products is not, in itself, an indicator of an eating disorder.
Because it was thought there was a connection
The idea that vegetarianism and eating disorders could be linked does not arise from the fact that a plant-based diet is considered dangerous.
Rather, specialists have long observed that some people with eating disorders may use restrictions apparently motivated by ethical or health reasons to limit food intake. In these cases, stopping eating meat can become a socially accepted justification for avoiding certain foods.
This has led some past studies to observe a greater frequency of vegetarian diets among people already suffering from anorexia or other eating disorders. However, this association does not demonstrate a cause-effect relationship: it is possible, in fact, that it was the eating disorder that led to the adoption of the diet and not the other way around.
The new meta-analysis reinforces this interpretation, showing that the simple label of “vegan” or “vegetarian” says very little about a person’s psychological health.
The motivation
According to the authors, the most important question is not what a person eats, but why he or she chose that diet. A person can eliminate meat for ethical, environmental, religious beliefs or for health reasons, maintaining a peaceful and flexible relationship with food. Another, however, may begin to exclude foods because they are driven by a strong fear of gaining weight, gradually introducing increasingly severe restrictions.
On the outside these two situations may seem similar, but from a psychological point of view they are profoundly different.
Only a few of the studies analyzed investigated the motivations behind food choice. In one of them, university students who had also adopted a vegetarian diet to control their weight showed a greater presence of eating disorder symptoms. However, the authors point out that the available evidence is not yet sufficient to draw definitive conclusions on this aspect.
Signs to pay attention to
According to researchers, assessing the risk of an eating disorder requires a much broader look than simply choosing not to eat meat.
A sudden change in diet, restrictions that become increasingly strict, significant weight loss, fear or anxiety related to food, strong discomfort during meals or a diet that does not guarantee adequate nutritional intake may represent alarm bells.
On the contrary, a vegetarian or vegan diet followed for some time, consistent with one’s values and well planned should not be considered a sign of risk.
The limits of the research
The authors themselves urge caution in interpreting the results. All the studies included were observational and photographed the situation at a single point in time, without being able to establish whether the diet was started before or after the possible onset of symptoms.
Furthermore, information on the quality of the diet, its duration and the motivations of the participants was often missing. Another limitation concerns the tools used: standard questionnaires on eating disorders could also interpret the exclusion of foods due to ethical or religious beliefs as a “restriction”, without distinguishing between a conscious choice and pathological behavior.
For this reason, researchers believe it is necessary to develop assessment tools more suitable for people who follow a vegetarian or vegan diet.
