New research suggests there may be a genetic link between anorexia and being someone who gets up early.
People with the eating disorder often wake early and experience insomnia, the new study found.
Experts say this differs from many other disorders which tend to be evening-based such as depression, binge-eating disorder and schizophrenia.
Our findings implicate anorexia nervosa as a morning disorder in contrast to most other evening-based psychiatric diseases and support the association between anorexia nervosa and insomnia as seen in earlier studies— Hassan Dashti, Massachusetts General Hospital
Senior author Hassan Dashti, from Massachusetts General Hospital (MGH), USA, an assistant professor of anaesthesia at Harvard Medical School, said: “Our findings implicate anorexia nervosa as a morning disorder in contrast to most other evening-based psychiatric diseases and support the association between anorexia nervosa and insomnia as seen in earlier studies.”
Past research has suggested a possible connection between eating disorders and the body’s internal clock, or circadian clock, which controls a wide range of biological functions such as sleep and affects nearly every organ in the body.
In the new study researchers looked at genes associated with anorexia, the body’s internal clock and several sleep traits including insomnia.
They found a two-way association between genes associated with anorexia and genes associated with morning chronotype, waking early and going to bed early.
The findings suggest that being an early riser could increase the risk for having anorexia, and having anorexia could lead to an earlier wake time.
However, the study did not define what time an early riser would wake up, with researchers instead saying that they tend to be natural early risers compared to the general population, with many things influencing when we wake up.
The study, published in Jama Network Open and led by investigators at Massachusetts General Hospital (MGH), in collaboration with University College London and the University of the Republic in Uruguay, also revealed a link between anorexia and insomnia risk.
Experts say more research is desperately needed into new prevention strategies and treatments for anorexia which has one of the highest death rates of psychiatric diseases.
Hannah Wilcox, lead author of the study and researcher at MGH, said: “The clinical implications of our new findings are currently unclear; however, our results could direct future investigations into circadian-based therapies for anorexia nervosa prevention and treatment.”
