Do you step on these misunderstandings of the daily science of good medical science 丨 summer sunscreen?

Sun protection is a top priority in summer. Paying parasols, wearing sunscreen, sunscreen ... People have tried their best to start with various ways and the sun. However, there are still many misunderstandings for sun protection. Today's good medical voice science invites Zhang Daojun, deputy director of the dermatology department of the Third Hospital of Chongqing Medical University, to teach you to avoid these misunderstandings to avoid sunscreen.

Expert Introduction

Zhang Daojun, deputy chief physician, member of the Communist Party of China, and deputy director of the dermatology department of the three hospitals. It is mainly engaged in skin surgery and laser beauty, and is especially good at diagnosis and treatment of skin and malignant mass and comprehensive diagnosis and treatment of scars.

Misunderstanding 1: Only sunny is sunny?

Truth: UVA in ultraviolet rays is not blocked by windows, parasols, etc., even in rainy days, it has the power to harm the skin, and UVB can be blocked by clouds, glass, clothes, umbrellas, etc. In other words, UVB usually exists outdoors, and it is stronger in summer or sunny; UVA is pervasive and indiscriminate in both seasons, rain and rain, indoor and outdoor. Therefore, even if you stood on a cloudy day for a day in winter and did not feel that it was exposed at all, the damage effect of UVA has long accumulated slowly in your skin to accelerate the aging of the skin. Therefore, even cloudy weather must not give up sun protection.

Misunderstanding 2: No need to wipe sunscreen if you hit an umbrella

Truth: The solar umbrella can effectively block ultraviolet rays, but can only block direct ultraviolet rays. It is not useful for ultraviolet rays such as ground reflection and glass window refraction. Only on the surface of the skin can be completely isolated from ultraviolet rays on the surface of the skin. In addition, sun protection must not only pay attention to the face, but also consider the neck, ears, back, arms, legs, feet, etc., and can choose suitable sunscreen products as needed.

Misunderstanding 3: The larger the SPF value, the better?

Truth: SPF refers to the protective power of UVB in ultraviolet rays. The coefficient behind SPF indicates the time when the skin can be sunburned by the skin. The larger the coefficient, the longer the time of extending the sunburn, but it does not mean that the better the sun protection effect. The US Food and Drug Administration said that the sunscreen index is 15, 30, 50, and 100 sunscreens, and its ability to prevent UVB from 93%, 97%, 98%, and 99%, respectively. The difference is not large. Because the higher the SPF products often contain more sunscreens, and these increased sunscreen damage to the skin is also inevitable, many people are prone to skin allergies after using high -coefficient SPF sunscreen. Perfect sun protection measures are not blindly increasing the sunscreen coefficient, but in time with the movement of time and sweating, so as to achieve the best sunscreen effect.

Misunderstanding 4: SPF and PA is the same thing?

Truth: PA refers to the protective power of UVA in ultraviolet rays, and PA uses "+" to measure the sunscreen coefficient of the product. The effective protection time of PA+is about 4 hours, the effective protection time of PA ++ is about 8 hours, and PA +++ is super strong protection. Because UVA's penetration ability is very strong, it can penetrate glass and clouds, and even penetrate some summer clothing until the skin dermis layer, which harms the skin more. Therefore, when sunscreen, you should try to choose PA +++ products to prevent UVA damage to the skin as much as possible.

Misunderstanding 5: sunscreen is directly used after toner?

Truth: For convenience, many people often apply sunscreen immediately after applying the toner, and even the sunscreen is directly applied without even the toner. This is very harmful to the skin. Sunscreen is the last step of skin care maintenance. It is the first step in the beginning of makeup. Do not simplify the steps because of greed to save trouble. Putting the sunscreen on the face without lipid protection will make the powder more opportunity to block the pores and induce acne and acne. And if it is a sunscreen with a high proportion of chemical sunscreen components, after absorbing sunlight decomposition, it will also cause more direct stimulation to the skin.

You need to do this correctly:

1. Football: The protection effect of sunscreen is generally coated with two milligrams of sunscreen products on one square centimeter. Calculating the amount of coins on the entire face is calculated. If the amount is too small, the protection effect will be discounted.

2. Apply items in advance: Apply sunscreen 15-30 minutes before going out can make it fully effective, especially if you need to launch the water immediately after wipe, you can wait for 15-30 minutes to be completely dry.

3. Make up in time: In order to ensure the continuous effect of sunscreen, when we are working outdoors for a long time, it is best to replenish sunscreen every 2 hours.

(Invited experts/Zhang Daojunwen/Wang Fengtu/Vision China)

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