When selecting a sunscreen, the first thing that catches the eye is often the label, such as 'SPF 50+' or 'PA++.' While a higher sun protection factor (SPF) or UVA protection grade (PA) may suggest a better product, the effectiveness of sunscreen is not solely determined by these numbers. Factors such as the duration of sun exposure, the environment in which one is active, and the proper application technique play crucial roles in its effectiveness.
First, it is essential to understand the meanings of SPF and PA. SPF indicates the level of protection against ultraviolet B (UVB) rays, with values up to 50 displayed numerically and anything above that marked as '50+'. PA signifies the level of protection against ultraviolet A (UVA) rays, with more '+' signs indicating greater protection. However, higher values may also increase the likelihood of skin sensitivity, so it is advisable to consider one's skin condition and activity environment when making a selection.
So, what type of product should one choose? Dermatologists generally recommend using a sunscreen with an SPF of 30 or higher. SPF 30 blocks about 97% of UVB rays.
If most of your activities involve commuting or staying indoors, a sunscreen with SPF 30 and PA++ or higher is sufficient. Conversely, for prolonged outdoor activities, hiking, sports, or swimming, products with SPF 50 and PA+++ or higher are recommended. Even water-resistant sunscreens should be reapplied after swimming or sweating. The key is not to choose the highest number but to select a product that fits your lifestyle.
When choosing a product, it is also important to consider the ingredients. Sunscreens are generally categorized into physical (mineral) and chemical (organic) types. Physical sunscreens work by reflecting UV rays away from the skin. They may leave a white cast but are typically less irritating. Chemical sunscreens absorb UV energy to block it, offering better spreadability but may cause irritation for sensitive skin.
Once you have selected a suitable product, the next step is proper application. Many consumers overlook the amount of sunscreen needed. For the face, it is recommended to use about the size of a 500-won coin, and for the entire body, about the amount of a shot glass. However, consistently applying this amount daily can be challenging.
According to the American Academy of Dermatology (AAD), most consumers apply only 20% to 50% of the recommended amount of sunscreen. Men often find the sticky texture off-putting, while women may worry about makeup smudging, leading to insufficient application. However, without applying enough, it is difficult to expect effective sun protection.
This makes the choice of formulation important. Creams are easier to apply in sufficient amounts on the face and are suitable for dry skin. Gels are good for oily skin or hairy areas, while sticks are convenient for applying to thin areas like around the eyes or for reapplication on the go. Sprays are popular among parents for easy application on children's skin, but it can be hard to ensure an adequate and even application. It is advisable to spray until the skin is sufficiently damp and then spread it with your hands.
Using sunscreen only in the summer is a common misconception. The sun emits UV rays regardless of the season, and a significant portion of UV rays can penetrate through clouds on overcast days. In winter, snow and ice can strongly reflect UV rays, exposing individuals to levels comparable to summer. In fact, the UV reflection rate from snow is reported to be around 80% to 90%.
To be effective, sunscreen must be used correctly. Apply a sufficient amount about 15 minutes before going outside, and reapply every two hours if engaging in prolonged outdoor activities or sweating. Choosing a product that fits your lifestyle and maintaining proper application habits are the most practical ways to reduce skin aging and damage caused by UV rays.
* This article has been translated by AI.
Copyright ⓒ Aju Press All rights reserved.