Vegetarian and vegan diets show no clear difference in eating disorder symptoms, large meta-analysis finds

Overview

A Nature briefing on a published article reports that a large systematic review and meta-analysis found no clear overall difference in eating disorder symptoms between people who follow vegetarian or vegan diets and those who eat meat. The study aggregates 24 cross-sectional studies involving 25,223 participants, using established questionnaires to assess symptoms, while clarifying that a dietary label alone does not diagnose or predict disordered eating. Original publisher: Nature.

• Diet labeling alone does not predict risk; motivation matters.
• Most studies are cross-sectional, so causality cannot be established.
• Qualitative research suggests discussing when the dietary change began and levels of flexibility.
• Screening tools tailored for vegetarians and vegans are being developed to improve assessment.

Overview

Vegetarian and vegan diets are adopted for various reasons, including animal welfare, religion, health, and environment. This article summarizes a systematic review and meta-analysis that evaluated whether strict vegetarian or vegan diets are associated with eating disorder symptoms. The analysis combined 24 studies with 25,223 participants. The included studies used established questionnaires to measure experiences such as food restriction, loss of control over eating, and distress about weight or body image. Importantly, these measures captured symptoms reported by participants rather than formal diagnoses of eating disorders. Diet definitions were strict: vegetarians excluded meat, poultry, fish and seafood; vegans excluded all animal-derived foods. Flexitarian, pescatarian, and semi-vegetarian diets were excluded due to differing motivations and dietary patterns.

Key findings show substantial variability across individual studies: some reported more symptoms among vegetarians or vegans, others reported fewer, and several found no clear difference. When results were pooled, there was no meaningful overall difference between dietary groups. The authors emphasize that a vegetarian or vegan label in itself does not determine psychological health, and that eating disorders can co-exist with these diets under certain circumstances.

Motivation matters is a recurring theme. Only a few studies explicitly examined why participants adopted vegetarian or vegan diets. In one university-based study, motives related to weight control partly explained higher eating disorder symptoms, but most studies did not document motivations, limiting their predictive value. The article argues that motivation can still inform clinical conversations, guiding inquiries about the onset of dietary change, whether fear or rigid rules emerged, and how much flexibility remains in the diet.

Limitations and measurement are highlighted. All 24 studies were cross-sectional, which prevents conclusions about causality or the direction of associations. There was limited information on diet quality, duration, and motivation, and most studies occurred in Western countries with relatively few adolescents or older adults. Nearly seven in ten participants were women, raising questions about generalizability to men and other groups. Standard eating disorder questionnaires were developed for the general population and may interpret ethical or religious food exclusion as unhealthy restraint; researchers are developing screening tools tailored to vegetarians and vegans. The authors caution against over-interpreting the absence of a direct link between dietary label and mental health and call for deeper assessment of underlying concerns and nourishment.

Implications for practice

The authors suggest that concerns about disordered eating should be taken seriously, but vegetarianism or veganism should not be treated as a sole warning sign. A more nuanced assessment asks why the diet was adopted, whether it has become increasingly restrictive, whether food triggers fear or distress, and whether nourishment remains adequate. For families and clinicians, this points to focusing on motivations, flexibility, and nutritional adequacy rather than the mere presence of a meat-free diet.

Conclusions

Labeling someone as vegetarian or vegan does not by itself determine psychological health outcomes. The findings indicate that a broader set of factors—such as personal values, fears, and dietary rigidity—are more informative. The study also underscores methodological gaps and the need for better screening approaches to distinguish ethical or religious commitments from disordered eating patterns.