Results show many points of interest. First, in the simplest models that include only our key variables of self-presentation, we see that unnatural hair colour predicts mental illness with a moderately large effect size, β = -0.33, and there is also a notable effect size for vegetarianism, β = -0.31. This relationship may exist due to vegetarianism being an expression of a need for a strong identity or perhaps because a high level of anxiety extends to anxiety about harm to animals. Having tattoos is comparatively a much weaker signal, with effect sizes estimated around -0.10. Across the models, we add progressively more potential confounder, such as age, sex and sexual orientation, political ideology and so on. However, we see that despite the inclusion of so any controls, unnatural hair colour remains a fairly potent predictor of mental illness, with an effect size in the final model of β = -0.23.
