The Diet on Wednesday passed a package of amendments that — for the first time in 140 years — includes a measure lowering the definition of adulthood to 18 years old from the current age of 20 but keeps the legal age for drinking, smoking and gambling unchanged at 20.

In addition, the package includes a revision to the Nationality Act, which currently obliges those with multiple citizenship to choose one by the age of 22. The revision moves the deadline to 20.

It also changes the age when a foreign adult qualifies to be naturalized in Japan to 18 from 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 various forms of 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 their legal age for wedlock 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.

Since this could lead to a rise in young people falling victim to fraud and other consumer issues, the Diet had already passed a separate bill during the ongoing session revising the Consumer Contract Act to beef up protections. The revision, for example, expands the scope of what are considered malicious contracts subject to annulments such as frauds involving the exploitation of romantic relationships to force victims to purchase goods.

The two-year drop will also apply to the age when an individual can start applying for a passport that is valid for 10 years. Those with gender identity disorder will be able to file paperwork with a court asking for a change to their officially recognized sex status at the age of 18, too.

One issue of concern related to the changes 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 hundreds of thousands of yen.

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.

Another focus will be whether to narrow the scope of the demographic that falls under the protection of the Juvenile Act.

Discussions have long been underway at the Justice Ministry over whether to exclude 18- and 19-year-old offenders from a series of protective and correctional measures stipulated by the law, including lighter sentencing.

While opponents say disqualifying them from correctional programs guaranteed by the law will result in a spike in re-offending, proponents argue that the prospect of stiffer penalties will serve as a deterrence.