Kim Young-soo, a political science professor at Seoul's Sogang University, said in a conference on Tuesday that adult movies, television dramas and instant noodle "ramen" made in South Korea are also selling "like hot cakes" in North Korea.
Skinny jeans refer to slim-fit pants that have gained popularity around the world, said Kim who interviewed about 2,000 defectors this year as part of a research project for the government.
He said that skinny jeans are so popular in the North's capital, Pyongyang, that people there sometimes mistakenly believe Chinese wearing the stylish clothes are roaming their capital.
"These are signs that North Korea is easing its isolation," Kim said in a telephone interview, noting that such lifestyle changes are conspicuous in Pyongyang and areas near the border with China.
The professor said many of the defectors he has interviewed had stayed in China no longer than a month before they came to South Korea, allowing him to have a relatively up-to-date glimpse of the latest culture in the communist country.
Kim said defectors told him pine mushrooms were also a "hit" among North Koreans this year because exports to South Korea had been diverted into the domestic market since cross-border tensions soared over the deadly March sinking of a South Korean warship.
After a multinational investigation in May found North Korea responsible for the sinking that killed 46 sailors, Seoul banned cross-border trade as part of its punitive measures.
Kim said blue crabs have met the same fate as pine mushrooms, allowing North Koreans to enjoy what was once a rarity for them.
The professor even told of a shop in which human manure could be traded to be used as an alternative to chemical fertilizer, an item on which the North had heavily depended from the South for years.
"Soondae," or sausage rolls stuffed with ingredients such as noodles and vegetables and wrapped in pig intestine films, has also made inroads into the market as a staple after the military stopped collecting pork and other food items from civilians, Kim said.
"These changes may not necessarily lead to greater ones in society, but they do bear a meaning," he said.
North Korea, one of the most impoverished countries in the world, remains under a raft of U.S. and U.N. sanctions for its defiant development and testing of weapons of mass destruction.
The country has a 1.2-million-strong army that critics say devours its natural and financial resources, while human rights abuses are rampant. The country botched a currency re-evaluation late last year, sending the prices of staples rising high and reportedly prompting the regime to publicly apologize to the people.
Despite the turbulence, a massive cult of personality continues to surround leader Kim Jong-il, who is in the process of engineering a power transfer to his third son, Kim Jong-un.
Pyongyang strictly controls any flow of information in and out of the country out of fear that outside influence may undermine its grip on the 23-million population. (Yonhap News)