Obese individuals are less likely to attempt suicide than those with normal weight... Why is that?

The hormone called Laptin plays a major role.Research findings show that overweight or obese individuals have a lower risk of making extreme choices compared to those with normal weight. / Photo = Getty Images Bank

According to News1 on the 13th, Professor Lee Seung-hwan's team from the Department of Endocrinology at Seoul St. Mary's Hospital, Catholic University College of Medicine, analyzed the relationship between BMI (Body Mass Index) registered in the National Health Insurance Service database in 2009 and the risk of suicide death for 4,045,081 people. The results of this study were published in the January issue of the international journal 'BMC Psychiatry'.

The researchers tracked the information of the study subjects until December 31, 2021. They also analyzed factors such as age, gender, income, smoking, alcohol consumption, exercise, the occurrence of mental illnesses, and the presence of chronic diseases such as diabetes.

As a result, the underweight group (BMI < 18.5 kg/m²) had a 1.44 times higher risk of suicide compared to the normal weight group (BMI 18.5-23 kg/m²). The underweight group also showed a relatively higher prevalence of diabetes, hypertension, dyslipidemia, and chronic kidney disease.

Women accounted for an overwhelmingly large proportion of 66.74% in the underweight group, and there were more cases of not smoking or not drinking alcohol.

Conversely, it was found that the likelihood of engaging in extreme behaviors decreases as weight increases. The risk ratio for the overweight group (BMI 23-25 kg/m²) was 0.79, for Obesity Group 1 (BMI 25-30 kg/m²) was 0.76, and for Obesity Group 2 (BMI > 30 kg/m²) was 0.71.

However, these results are known to be unrelated to the presence of major depressive disorder, housing type, or lifestyle.

The researchers explained, "The hormone 'leptin,' produced in adipose tissue, sends signals to the brain to regulate hunger and energy balance. Obesity causes the brain to become less responsive to leptin," and added, "Increased resistance to leptin can alter the brain's 'reward processing pathway,' which paradoxically may reduce impulsivity in certain situations."

Next, psychological factors such as body image, feelings of victimization and bullying, eating disorders, and sleep problems may be related to the risk of extreme choices and underweight conditions. It was also added that in order to reduce mortality due to extreme choices in the future, public health resources should be reviewed and invested by the government and related agencies.