Since the beginning of summer
The high temperature in Nanyang has continued
Sun protection has not been done
Aging over the summer
The state of the skin
Directly widens the gap between your appearance and your peers
In response to the "BBQ" mode
friends in Nanyang
have Come up with your own sunscreen "artifact"
sunscreen spray, sunscreen, parasol, sun hat, sun protection clothing , sunglasses... Can the dazzling array of sunscreen products play the role of preventing sunburn and suntan? How to avoid "stepping into thunder" when choosing sunscreen products?
Nanyang Medical College
The First Affiliated Hospital Department of Dermatology
Chief physician Chen Ning
Introduced to us
Many people’s misunderstandings about sun protection
Come and check it out
1.I am not afraid of tanning and do not need sunscreen
Facial wrinkles
75 % is produced by sunlight
Ultraviolet rays in sunlight
are not only the main cause of skin aging
Excessive ultraviolet rays
can also cause pigmentation
Solar dermatitis
Skin burns
increased skin cancers
such as malignant melanoma
Risk of squamous cell carcinoma
Ultraviolet light is a kind of light with a wavelength between 100 nm and 400 nm, which is divided into short-wave UVC, medium-wave UVB, long-wave UVA. The short-wave UVC in the sun cannot reach the surface of the earth. Our sun protection mainly protects against medium-wave UVB and long-wave UVA. UVB will cause skin redness and sunburn, while UVA will tan the skin and even cause skin cancer.
2. I always apply sunscreen before going out, so I won’t get sunburned.
Applying sunscreen
must reach a certain thickness
to have sun protection effect
The international standard is 2mg/cm²
is about the thickness of 2 sheets of paper
the whole sheet The amount of sunscreen used on the face is about
The amount of sunscreen the size of a one-yuan coin
Sunscreen products should be applied
for several hours
Due to dilution of sweat and other reasons
the sunscreen effect will gradually weaken
and need to be reapplied in time
The sunscreen is applied too thinly and unevenly
No Timely reapplying
will greatly reduce the sun protection effect.
Sunscreen and sun hat,
sun protection clothing, sun protection umbrella, etc.
The effect is better when used in conjunction with physical shielding sunscreen.
Cosmetic sun protection is divided into ultraviolet rays. Reflective (physical sunscreen) and There are two categories of UV absorbing (chemical sunscreen).
The main ingredients of physical sunscreen are inorganic chemicals such as titanium dioxide and zinc oxide . They are relatively thick and greasy and have a whitening effect, but have little irritation to the skin. Sensitive skin can be used for sun protection immediately after application; The main ingredients of chemical sunscreen are benzophenone , octocryline , avobenzone, and benzotriazole. The color is relatively natural and refreshing, and the sun protection index is high, but it will be irritating to the skin. And while absorbing ultraviolet rays, it is also decomposing itself. Generally, it needs to be reapplied after 2-3 hours.
SPF represents the sun protection strength (UVB protection) of sunscreen. The higher the SPF value, the stronger the sun protection effect, which can effectively prevent sunburn; while PA represents the sun protection strength (UVB protection). The higher the PA value, the sun protection The black effect is stronger.
3. When you go out and sit in the car, you can’t get any sun
Ordinary car window glass
cannot completely block ultraviolet rays
In addition,
ultraviolet rays entering the eyes
will also damage the cornea and pupil
lens, vitreous body , retina
cause damage
increase cataracts , pterygium
and other eye diseases
Drivers who drive for a long time
need to wear
sunglasses with UV protection
This famous photo from the New England Journal of Medicine, the protagonist is a 69-year-old truck driver. I have been driving for 28 years. Since the left face has been exposed to the sun for significantly more time than the right face, the aging condition of the left face is obviously more serious than that of the right face.
4. It has been cloudy and rainy in the past few days, and the sun is not strong, so sun protection does not need to be so strict.
The intensity of ultraviolet rays on cloudy days can reach up to about 70% of that on sunny days. It has almost no isolation effect.
90% of ultraviolet rays are Can penetrate clouds
Let’s take a look at the results of testing with ultraviolet test cards on rainy days
There is still near-moderate intensity of ultraviolet rays outdoors on rainy days
From 10:00 to 14:00 in Nanyang summer from June to August
Ultraviolet rays in sunlight are
The most intense time
Don’t relax when it comes to sun protection
