Do Night Runners Need Sunscreen? MFDS Says "UV from Streetlights Has Minimal Impact"

Sunscreen Can Trigger Skin Trouble on Sweaty Skin...
Thorough Cleansing of Arms, Legs, and Neck Is Essential

Due to the hot weather, more people are choosing to go running at night instead of during the day. In response to the question of whether sunscreen needs to be applied during nighttime workouts, the Ministry of Food and Drug Safety stated that it is not necessary to wear sunscreen at night.

Image generated by AI to aid understanding of the article.

Recently, the blog and YouTube channel of the Ministry of Food and Drug Safety (MFDS) received the question, "I'm a runner who goes out at night after work. Should I still apply sunscreen at night?" To this, the MFDS replied, "There is no need to use sunscreen at night." The MFDS explained that the reason is "the ultraviolet rays emitted from streetlights or indoor LED lighting are not strong enough to affect the skin." Additionally, they advised, "On the contrary, repeatedly applying sunscreen on skin already sensitive from sweating may lead to clogged pores and increase the risk of skin trouble such as pimples." Dr. Shin Seungyong also commented, "The process of cleansing can damage the skin barrier," and added, "It is good for your skin to take a break as well."

To the second question, "Is it necessary to thoroughly use a cleansing product for the sunscreen applied to the body?" the MFDS stated that "during the summer, or for outdoor activities, sunscreens often have ‘waterproof’ properties so they do not wash off easily with sweat or water." They further explained, "Such products do not get removed completely with water or regular soap and can linger on the skin, and when the sunscreen ingredients remain, they may block pores, causing itching or contact dermatitis." The MFDS stressed, "Just as you carefully wash your face, it is also important to thoroughly clean areas where you applied sunscreen such as your arms, legs, and neck." In other words, if you used waterproof sunscreen, it is necessary to use a primary cleanser such as cleansing water or cleansing oil, or a dedicated body cleanser with strong cleansing capabilities, to thoroughly remove the product.

Ultraviolet rays are a major cause of skin aging and pigmentation such as melasma and freckles. In particular, ultraviolet A (UVA) affects tanning and aging of the skin, while ultraviolet B (UVB) can cause redness or sunburn.

When selecting sunscreen, you should check the SPF and PA ratings, which indicate sun protection efficacy. SPF shows the level of protection against UVB, while PA indicates protection against UVA. If the SPF is below 50, the number is listed, and if it is 50 or higher, it is marked as '50+'. The PA level is displayed on a scale from 'PA+' to 'PA++++', in four steps. The higher the number or the more pluses, the stronger the protection.

During the daytime, you should select products based on the duration of your activities and degree of sun exposure. If you spend most of your time indoors or have limited outdoor activity, such as a short walk, it is recommended to use products with at least SPF15/PA+. For sports or prolonged exposure to sunlight, SPF50+/PA+++ or PA++++ is recommended. In environments where sunscreen may be washed off, such as swimming pools or beaches, it is best to use products labeled as 'water-resistant' or 'very water-resistant.'

Sunscreen should be evenly applied to exposed skin and allowed to dry for at least 15 minutes after application. For prolonged outdoor activity, as sunscreen can be removed by sweat and other factors, it is recommended to reapply every two hours. The MFDS emphasized the importance of selecting sun protection products that suit both your skin type and your activity environment.

This content was produced with the assistance of AI translation services.