A 19-year survey of 4,363 British civil servants by researchers at University College London has found that those who suffered from anxiety and depression were more likely to become obese. The participants were screeened four times over the course of the study with each screening assessing them for common mental disorders and measuring their height and weight. Weight gain was more common in people with mental disorders at the start of the study. Those participants who showed signs of mental disorder in the first three screenings were twice as likely as symptom-free people to be obese by the end of the study. Those who experienced more incidences of common mental disorders had a greater risk of weight gain and obesity but there was no evidence of a relationship in the other direction i.e. people who were obese at the earlier checks were no more likely to develop depression and anxiety later than slimmer people.
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