Tokyo >> For the first time in 140 years, the definition of adulthood in Japan has been lowered two years to 18 years old but keeps the legal age for drinking, smoking and gambling unchanged at 20.

The Diet passed the package of amendments last month that includes a revision to the Nationality Act, which forces those with multiple citizenship to choose one by the age of 20 from 22.

Under the new laws, a foreign adult qualifies to be naturalized in Japan at age 18 instead of 20.

The two-year drop will also apply to cases where a child born into an international marriage seeks to obtain Japanese citizenship, with the revised law stating that the child’s application must be completed by the age of 18, according to a Justice Ministry official.

The new definition of adulthood — the first such change since it went into force in a 1876 Meiji Era edict — will take effect on April 1, 2022. The change follows a similar move by the Diet in 2015 that saw the lowering of the voting age to 18 from 20.

The package of amendments, however, will keep unchanged the minimum legal age of 20 for activities such as drinking, smoking and state-run gambling, including horse, bicycle and motorboat racing.

The measures will also put women on par with men in terms of when they can get married, moving the legal age for wedlock for women to 18 from 16.

It will also enable 18- and 19-year-olds to apply for loans and credit cards without the consent of their parents.

One issue of concern is the possible effect on the annual coming-of-age ceremony and the ever-shrinking industry for traditional female kimono.

Adulthood at 18 means that most of those attending the annual ceremony, which is typically held by municipalities in early January, will be third-year high-school students who are also gearing up for college entrance exams only a few weeks away. That means they could be too busy to take part in the annual tradition or too preoccupied to rent a kimono, which could cost thousands of dollars.

The lowered age of adulthood will likely deal a “huge blow” to the nation’s kimono industry, according to Hidemitsu Miyamoto, president of the Kanagawa-based kimono firm Kimono Kuroudo Miyamoto.

“The coming-of-age ceremony has been something of a final stronghold for our industry’s survival at a time when fewer and fewer people wear kimono, presenting what is perhaps the only opportunity for young people, especially women, to don the attire,” Miyamoto said.

“The new age of adulthood will probably bring about a huge change in the norms of the ceremony. … But from our point of view, I hope that the 20-year-old turning point will still be cherished, regardless of the legal change,” he said, noting that he also wants municipalities to keep the age of the event unchanged at 20.