Japanese children had the second-worst rated mental well-being among 38 developed and emerging countries due to poor life satisfaction and the high frequency of suicide, a UNICEF report said Thursday.

While Japanese children ranked first in physical health and live in relatively well-off economic circumstances, instances of bullying in schools as well as difficult relationships with family members leads to a lack of psychological well-being, the U.N. Children's Fund found.

Elementary pupils head to school in Nagoya in August 2020. (Kyodo) 

Only children in New Zealand ranked worse than Japan in terms of their mental well-being.

The report, titled "Worlds of Influence: Understanding What Shapes Child Well-being in Rich Countries," looked into three key categories -- mental well-being, physical health, and academic and social skills -- using data collected before the novel coronavirus pandemic.

Taking into account all three categories, the Netherlands topped the list, followed by Denmark and Norway. Japan landed 20th, the United States 36th and Chile ranked worst among nations included.

The paper's findings were based on U.N. statistics covering members of the Organization for Economic Cooperation and Development and the European Union.

In 2018, the Netherlands reported the highest rate of 15-year-old children who had a high life satisfaction at 90 percent, while Turkey ranked bottom at just 53 percent. Japan came in second last at 62 percent.

In Japan, an average of 7.5 in 100,000 adolescents aged 15 to 19 committed suicide between 2013 and 2015, while the suicide rate for New Zealand was the second-highest at 14.9. Greece saw the lowest suicide rate at 1.4, while Lithuania saw the highest at 18.2.

Meanwhile, Japan logged the lowest obesity rate with just 14 percent of those aged between 5 and 19 classified as overweight or obese in 2016. The United States had the highest rate at 42 percent.

In academic proficiency and social skills, Japan placed 27th.

Although Japanese children ranked fifth in reading and mathematics proficiency, they were second from bottom when it came to confidence in making friends easily, with just 69 percent of 15-year-old students saying they felt that way, only better than the 68 percent reported by Chilean kids.

Japan had the lowest unemployment rate in 2019 among the countries included, and the rate of children living in poverty stood at 18.8 percent, below the average 20 percent.

Japanese education expert Naoki Ogi labeled Japan's schools a "bullying hell" and said excessive competition to get into prestigious schools proves a negative factor to children's mental health.

"It's inevitable for children (in Japan) to have low self-esteem and lack a sense of happiness," he said.

Looking forward, the UNICEF report said the ongoing coronavirus crisis will add to challenges faced by children.

"What started as a health crisis will spread to touch all aspects of economies and societies," it said. "Children will not suffer the worse direct health effects of the virus. But as we know from previous crises, they will be the group that experiences the longer-term negative impacts most acutely."