Xiao Yu (not her 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," said 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 that Xiao Yu 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," warned 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 photography 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 said 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," said the 56-year-old.

The association boss explained 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," said 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," said 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 ($450), 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," explained 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 added, 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, said 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 said. "It is exactly the same with photography."

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

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