"Fever underwear," hot underwear fever Ye Hao different opinions
Shaoxing Harbour Textile&Garments Co., Ltd , https://www.sxharbour.com
July 11, 2025
As the weather forecast predicted, northern regions are expected to experience a drop of 10 to 12 degrees Celsius. Yesterday, reporters observed a surge in demand for "heating underwear" in several major shopping malls across Shenyang. This new trend is gaining popularity as people prepare for the upcoming cold snap.
According to a sales associate at one of the stores, "Wearing this type of thermal undergarment allows you to layer a thin sweater or jacket without feeling the chill. It also prevents the uncomfortable bloating that often comes with heavy winter clothing." The sales staff noted that the product has been selling well, with several sets sold daily. Each piece of "fever underwear" is labeled with claims of using "high-tech materials" and being made through a "special process." The key feature is its ability to generate heat, which makes it significantly more expensive than regular thermal wear—often three to four times the price. A standard set can cost around 600 yuan.
At first glance, these undergarments look similar to regular thermal wear. However, the main difference lies in their heating function. Salespeople from different brands all claimed that their products are capable of warming the body, though the exact mechanisms vary. One brand described its material as "Ik Silk," which they claim has a natural heating property. Another brand introduced a high-performance fiber called "Lunese," developed using special blending technology that converts body moisture into heat energy.
In another section of the mall, a promotional board for "Double Salam" attracted several customers. The promoter explained that their heating underwear uses a unique Japanese spray technology, incorporating far-infrared ceramic fibers that create a warming effect. Another brand, known as "Outlast," claims to offer smart thermoregulation. According to the salesperson, their underwear absorbs excess body heat when it's warm and releases it when it's cold, maintaining a balanced temperature. "It’s like your own body heat is reflected back by the underwear—it’s very advanced," the salesperson said enthusiastically.
But do these fibers actually generate heat on their own? Wang, a professor from the School of Physics at Liaoning University, questioned the scientific basis behind the "heating principle." He pointed out that heat is generated through movement, and any material that claims to produce heat must absorb energy. Where does this energy come from? An engineer from the provincial textile research institute also expressed skepticism, stating that he was not aware of any material that could automatically generate heat.
When contacted, the China Knitting Industry Association confirmed that there are indeed heating fibers developed by a Japanese R&D company. However, due to limited raw material supply, production remains low. To verify authenticity, the association suggested checking for a yellow "fever underwear" logo on the packaging, which serves as a quality assurance mark. Even if genuine, these undergarments cannot fully replace traditional cotton garments in terms of comfort and breathability.
Reporters also learned from the provincial quality inspection department and business authorities that there are currently no national standards for heating underwear in China. As a result, consumers who purchase counterfeit products may find it difficult to seek third-party verification or legal recourse. This lack of regulation raises concerns about the reliability and safety of such products.