The practice of washing the face first with warm water and then with cold water to prevent acne is counterproductive and might harm the skin, a dermatologist said on Wednesday.
Linkou Chang Gung Memorial Hospital physician Huang Yu-huei (黃毓惠) told a news conference at the Food and Drug Administration (FDA) that she frequently treats patients for eczema or other skin conditions caused by unhelpful facial care practices.
She said many patients want to eliminate their acne and washed their face with warm water to enlarge the pores, applied facial cleanser and washed it off with cold water to shrink the pores.
Huang said the practice can damage the hydrolipidic film on the skin, leading to more acne outbursts.
A study suggested that the ideal water temperature for washing the face is about 25°C, or a little cooler than body temperature, as hot water can overstimulate the facial skin, Huang said.
Acne outbursts are associated with abnormal sebum production, which can be triggered by a lack of sleep and keeping irregular hours, she said.
“Washing the face too often or overcleaning it will harm the skin,” Huang said, advising people not to wash their face more than twice per day — in the morning and at night.
The FDA also gave five tips for proper facial care: Choosing products that are clearly labeled and that match the user’s skin condition; washing the face with cool water; moving the hands slowly when applying a facial cleanser; not keeping the cleanser on the face for too long; and not washing the face too often.
Huang said some people think that using facial cleaning products that claim to have multiple benefits is good for the skin, but the products usually stay on the face for a short time and cannot show the desired effects, but added that leaving them on the face for too long might overstimulate the skin.
Most facial cleansers are listed as general cosmetics, FDA Division of Medical Devices and Cosmetics section head Hung Kuo-teng (洪國登) said, but added that the FDA has given permits to 66 products that contain drug substances, such as salicylic acid, for acne prevention.
The FDA urged people to choose cosmetic and skin care products carefully, and notify the agency via its online cosmetic quality management system (http://qms.fda.gov.tw/tcbw) if adverse reactions occur.