Eating Disorder ARFID Is Highly Heritable, Study Finds

Avoidant restrictive food intake disorder, ARFID, is highly influenced by genetic factors, according to a large twin study conducted by Swedish researchers.

ARFID is a serious eating disorder characterized by the avoidance of certain types of food due to its smell, taste, or texture. People with ARFID may not eat certain foods because of previous unpleasant experiences, such as choking or poisoning. Lack of appetite can be another sign of the disorder.

Contrary to anorexia or bulimia, ARFID is not caused by a fear of gaining weight. But as with other eating disorders, it leads to malnutrition and nutritional deficiencies.

The study, the findings of which were published in JAMA Psychiatry, included nearly 17,000 pairs of twins in Sweden born between 1992 and 2010. Of those, 682 children with ARFID between the ages of six and 12 were identified.

To determine the influence of genes on the onset of the disease, the researchers at the Karolinska Institutet in Sweden used the twin method. They discovered that genetic factors explain 79% of the risk of developing ARFID.

"This study suggests that ARFID is highly heritable. The genetic component is higher than that of other eating disorders and on par with that of neuropsychiatric disorders such as autism and ADHD," says Lisa Dinkler, a postdoctoral researcher at the Department of Medical Epidemiology and Biostatistics at Karolinska Institutet.

An estimated one to 5% of the world's population suffers from ARFID. The disorder may look different from person to person, but the common feature in all people with ARFID is avoidance or restriction of food intake.

ARFID can negatively impact a person's physical and psychological well-being because avoiding food may lead to serious weight loss and nutritional deficiencies that require treatment. People whose food intake is very limited may be prescribed nutritional supplements or, in more severe cases, tube feeding.

The signs of ARFID may include:

• Eating much less food than is necessary to stay health
• Difficulty in recognizing the feeling of hunger
• Feeling full after eating a small amount of food and struggling to eat more
• Taking a long time over mealtimes or missing meals completely
• Sensitivity texture, smell, temperature, or other aspects of foods
• Always eating the same foods or only eating foods of similar color
• Weight loss
• Developing nutritional deficiencies

If you suspect you might have ARFID, you should make an appointment to discuss this with your doctor.