Xiao Yu (not real name) smiled as she flipped through her favorite photo album - a collection of nude portraits she recently posed for at a Beijing studio. "A beautiful body deserves pride," says the 23-year-old. "I wanted to preserve the memory of youth, when the body is at its physical peak." Although unabashed in private, perhaps the fact Xiao did not want to be quoted under her real name for fear of upsetting her family or bosses at the media organization where she works tells a different story.

A growing number of Chinese people are now choosing to go nude for posterity, particularly young women and new brides. However, the trend is not supported by everyone.

"Nude photos are unhealthy," warns He Lina, chairwoman of the Shanghai Wedding Trade Association, a group that is urging authorities to ban studios from the practice.

And it is not just a matter of morality; critics also claim the images could be misused and even illegally distributed as pornography.

Few photograpy studios make a big noise about their nude services, either in-store or online, yet the vast majority are taking advantage of the peak in demand.

Photographers who talked to China Daily say customers fall largely into three categories: College students, newlyweds and women aged about 30 who want to "capture their shapes" before they have a baby.

According to Zhou Xiaozheng, a sociologist at Renmin University of China, the development proves China has "diversified from its conservative past" and boasts a more open social atmosphere.

However, He in Shanghai, whose group is pushing for a clampdown on studios, dismissed the trend as simply "a novelty" and claimed nude bridal shoots "show disrespect to the country's wedding customs, which are traditionally sacred and serious".

"We were young once and we understand the idea of wanting to keep a memory of that eternal beauty, but that doesn't justify taking nude photos that have nothing to do with art," says the 56-year-old.

The association boss explains that her favorite picture was taken when she was about 20 years old. In it, she is wearing a white shirt and blue trousers, a typical outfit at the time.

"The clothes were not tight but I can still make out my curves," says He. "I think this is a good way to remember my youth. You don't have to be naked."

Market takes off

Many people disagree with He. Industry insiders say the photography market is booming, thanks to massive demand for naked portraits. And it is not just in China's more fashionable cities.

From Harbin in far northeastern Heilongjiang province to Chengdu in far southwestern Sichuan province, professional studios are reporting an increasing number of inquiries about nude shoots.

"I first noticed the phenomenon when I began working in Shanghai (six years ago) but it's no longer a small thing," says Wei Tianjian, 45, a Taiwan native who works at a prestigious studio in Shanghai. "I've already taken nude portraits for two women this year and I'm just one of nine photographers here."

The popularity has also boosted profits, with most businesses charging extra for clients who want the "stripped down" option.

At Dayu Photo Studio, a company that has branches throughout China, a nude shoot costs 2,999 yuan (about 340 euros), four times that of its standard portrait service.

"When (the model) doesn't have any clothes on, it's more demanding for the photographer to design the layout, find the perfect angles and create an ideal effect," explains a 30-year-old customer service manager surnamed Ou at Dayu's Beijing office.

"The pictures can be indoors or outdoors, the model can cover the most private parts with a flower, a piece of chiffon or they could use nothing at all. They are the decision-makers about their photos," she says, while showing some sample pictures published on the company's website.

Xiao Yu, who admitted to going on a two-week diet before her shoot as she did not want to see her "muffin top" years later, says she feels nude pictures are about women being outgoing and confident, and have nothing to do with being disrespectful.

"Girls used to wear one-piece swimsuits but now many prefer bikinis, which indicates an open-mindedness in the new era," she says. "It is exactly the same with photography."

Several psychologists also endorse nude photographs as a way to appreciate youth, suggesting that it is helping Chinese society break a long-standing taboo.

"We keep photos of naked babies; why can't we keep those of our mature bodies?" asks Ji Xuesong, deputy chief physician at Peking University's clinical psychology center.

Keeping it private

One aspect that has prevented many women from jumping on the bandwagon is privacy - and the potential danger their photos could fall into the wrong hands.

"What if they are leaked?" says Wu Xia, a 22-year-old sales clerk at a multinational consumer goods company in Wuxi, Jiangsu province, who is clearly appalled at the idea of posing for nude pictures.

Although photographers naturally own the creation rights of their work, under Chinese law customers own the portrait rights of such photos, which means if the images are distributed by studios they will face legal penalties.

"Also, charges over pornography (illegal in all forms) would be inevitable if the photos were posted on the Internet," says Shi Yu, 50, a photography expert and deputy director-general of the China Association of Social Workers' Committee of Wedding Service Industries.

To put customers at ease, studios often sign confidentiality contracts that promise whopping sums of money in compensation should the photos be improperly distributed.

"We'd be in big trouble if the photos got out, not only legally but our reputation would be severely damaged," says Ou at Dayu Photo Studio. "We want to get more business in the future, so we're not going to put our neck on the line like that."

He says staff members do all they can to ensure clients' privacy, explaining that the retouching of photos is always done in a private room, while software installed on the computers monitors and records the use of any flash drives or other "removable discs".

"All photos are deleted from the computer in front of the customers as soon as they are given their copies and all samples used on the website are with customers' permission," Ou says.

There are no laws or regulations concerning nude art photography or the qualification of a studio to provide the service, according to legal experts. That means, as long as businesses do not violate public order, the pictures are acceptable.

However, as Wei in Shanghai pointed out, contracts and strict company rules only prevent gentlemen, not villains.

"It is our duty to remind young people that we live in the digital age," Yi Shenghua, a lawyer at Beijing Yingke Law Firm, says. "They should be clearly aware of the potential hazards."

Trouble for teens

Nude portraits, as an artform, are permitted by the central authorities. Yet, some social analysts claim the new trend for photos among young people is moving away from artist creation and into "unhealthy" commercialization.

In the past, photographs and drawings of naked women could be viewed only in galleries and public exhibitions. Today, albums of the pictures can be bought at markets.

"Nude art is at risk of being misused in commercial circles," says Wei Pishen, 54, chairman of the Shanghai Photography Trade Association. "So, if photographic art is becoming a business service, that could cause trouble."

The changes in social values and sexual liberation that nude photo shoots are said to represent could also hinder the development of teenagers, says Xia Xueluan, a professor of sociology at Peking University.

"Juvenile crime has continued to worsen, especially sexual crimes, to which the open-mindedness of the public and the easy availability of scantily clothed men and women both make great contributions," he says.

"In primitive times, people knew to cover their bodies with leaves. Why are people now taking off their clothes? How can youngsters cast aside etiquette and shame?"

He Lina in Shanghai has a daughter in her 20s. In her bedroom hangs a picture of her playing tennis in a gymnasium, her hair in braids, which He thinks is the right image for teens to learn from.

However, photography expert Shi Yu argues people such as He and Xia are simply trying to hold back history.

"Three decades ago, many things we are doing today were prohibited. Who is to say what will be acceptable in 10 years?" he says.