Insights into New Genetic Link Between Anorexia Nervosa and Being an Early Riser

New research indicates that the eating disorder anorexia nervosa is associated with being an early riser, unlike many other disorders that tend to be evening-based such as depression, binge eating disorder and schizophrenia.

Previous 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.

This study aimed to further understand this relationship by assessing genes associated with anorexia nervosa, the circadian clock and several sleep traits including insomnia.

The investigators used a statistical method called Mendelian Randomization to see how genes that are associated with a certain trait affect other traits of interest.

For example, examining the sleep patterns of people with genetic differences that makes them more likely to have anorexia nervosa, this provides evidence on the relationship between anorexia nervosa and sleep.

They found a two-way association between genes associated with anorexia nervosa and genes associated with morning chronotype (waking early and going to bed early).

In other words, the findings suggest that being an early riser could increase the risk for having anorexia nervosa, and having anorexia nervosa could lead to an earlier wake time.

The team also found an association between anorexia nervosa and insomnia.

“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,” says senior author Hassan S Dashti, PhD, RD.

Treatments for anorexia nervosa are limited and current treatments have relapse rates of up to 52%. In addition, the cause of the disease is still unclear.

With anorexia nervosa having the second highest mortality rate of psychiatric diseases, more research is desperately needed into new prevention strategies and treatments.


Hannah Wilcox, Valentina Paz, Richa Saxena, John W. Winkelman, Victoria Garfield, Hassan S. Dashti. The Role of Circadian Rhythms and Sleep in Anorexia Nervosa. JAMA Network Open, 2024; 7 (1): e2350358 DOI: 10.1001/jamanetworkopen.2023.50358

Massachusetts General Hospital. “Study reveals new genetic link between anorexia nervosa and being an early riser.” ScienceDaily. ScienceDaily, 4 January 2024. <>.

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