14 frequently asked questions about sunscreen

Using "sunscreen" is an important step to help you protect your skin from the effects of the sun, keeping it bright, radiant, and smooth.

Did you know "sun protection" is one of the important steps to help you protect your skin from the effects of the sun and ultraviolet rays? This is also one of the steps to help the skin always keep its bright, radiant, smooth features and minimize the risk of darkening, sunburn, brown spots, freckles, age spots but little attention is paid to women. . Therefore, let's briefly skim some information below to better understand and choose for yourself the most suitable sunscreen product!

1. Do you need to use sunscreen?

Dr. John Ashworth, a British dermatologist confirmed: "A lot of people think a little sunburn is okay. However, lying in the sun without any protection is like smoking 80 cigarettes a day.

The greenhouse effect causes the ozone layer to thin, in some places it is punctured (the ozone layer is like an umbrella that blocks most of the earth's ultraviolet rays), the number of people with skin cancer is increasing rapidly, which are the reasons for them. We need sunscreen.

2. If you use sunscreen, you can sunbathe freely without fear of darkening your skin?

Wrong. No sunscreen can protect you from the sun 100% of the time. Women still find that their skin will be a little darker if exposed to the sun for a long time, even though they have applied sunscreen. (There was a time when Ha played tennis from 7.30am to 9am, applied sunscreen with SPF 81+, but still tanned. It took nearly 6 months to take care of and nourish her skin to "release the sun" back to the way it was.)

3. Sunscreen with SPF 30 is twice as effective as a sunscreen with SPF 15, right?

Wrong. UV protection is not directly proportional to SPF. Sunscreen with SPF 15 absorbs up to 94% of UV rays, SPF 20 absorbs up to 95%, SPF 30 is 96%, SPF 45 is 97%, SPF 60 is 98%.

4. Is a higher SPF sunscreen better than a low SPF sunscreen?

True but not enough (see also verse 3). As you can see above, SPF 30 or higher, the ability to absorb ultraviolet rays is not much different. Low SPF (20-40) sunscreen is suitable for the face and delicate areas. A higher SPF will allow you to stay in the sun longer.

Each SPF unit provides 10 to 15 minutes of protection.

For example: If you buy 1 sunscreen product with SPF 30, take 30 x 10 (or 15) = 300p (or 450p) equivalent to 5 hours (or up to 7.5 hours) is the time to protect the skin from being damaged. catch the sun. After this time, if you are still exposed to the sun, you should reapply.

If you sweat a lot when playing sports or swimming, you should reapply sunscreen every few hours.

Tip: Always use sunscreen with SPF>15

Dr. John Ashworth (British dermatologist) emphasized: "I think anything with an SPF of less than 15 is worthless. If you only use a small amount on hot days, the protection is less because sweat quickly washes it all away.

The figure below shows the sun protection of different SPF ratings (lighter color means less sunburn). You can clearly see that with SPF below 15, the skin is very little protected.

5. Should you apply sunscreen before or right after going out in the sun?

Any sunscreen takes 20-30 minutes to fully penetrate and create a wall to block ultraviolet rays (also known as ultraviolet rays or UV rays). For the best sun protection, you should apply sunscreen 20 minutes before going out in the sun.

6. If it's cloudy, you don't need sunscreen?

Wrong. UVA rays are still intact even though it's overcast (UVA causes melasma, skin aging and wrinkles), so don't be subjective when it's overcast or in the shade.

7. How can I use sunscreen if I have makeup on?

Many cosmetics are equipped with sun protection such as sunscreen, indicated by the SPF and PA numbers on the outside of the shell.

8. When applying makeup with cosmetics with different sun protection index, how do you know how much you are being protected with?

SPF numbers do NOT add up when you apply two types of sunscreen but only take the SPF of the highest. For example, if you apply a foundation with SPF17 while the powder is SPF20, the sun protection factor for your skin at that time is 20.

9. Can a full body sunscreen be used on the face?

Usually on the sunscreen bottles are written "can be applied to the face and sun-exposed areas". But as you know our facial skin is often thin and easily irritated, so it is recommended to use a sunscreen specifically for the face because they have added skin-nourishing essence, the best SPF is about 20-40. An SPF higher than 40 should be used on other areas of the body. Using the wrong indicator can cause irritation and acne. The most suitable dosage to apply to the whole face is about 2.5g.

10. With different skin types, how should I choose sunscreen?

If you have sensitive and acne-prone skin, you should pay more attention to this issue.

For sensitive, allergy-prone skin, choose a sunscreen that does not contain paraaminobenzoic acid (PABA), which contains ingredients such as titanium dioxide and zinc oxide. Try the product on your wrist before you buy.

- If you have acne-prone or dry skin, you should use a mist or spray form, because this type is gentle and unclogs pores, helping the skin not to be blocked by dust and sweat.

- Oily skin, you choose products with oil-free; or non-comedogenic; (doesn't cause acne).

- In addition, depending on skin pigmentation, you should use the appropriate SPF index. The lighter the skin, the easier it is to catch the sun, so choose a higher index than darker skin.

11. How long is the shelf life of a bottle of sunscreen?

Like other cosmetics, 6-8 months from the date of opening the product is the ideal time to use.

12. Do you need to apply sunscreen on other skin areas?

Candlestick. In addition to the skin of the face, hands and feet, you should pay attention to applying sunscreen in other neglected areas such as the earlobes, hairline, elbows, ankles, and heels. Sunlight can damage all areas of the skin.

13. Can the sun penetrate through clothes?

Maybe. Each type of clothing has a different sun protection effect, called the UPF (Ultraviolet Protection Factor). The higher the UPF, the greater the ability to absorb ultraviolet rays, the safer your skin will be.

Clothing provides protection in all three ways: fabrics can block UV, colors can absorb or reflect UV rays, and some chemicals on fabrics can absorb UV rays. Clothing with a UPF of 50 means only 1/50th of UV rays can pass through.

14. How to choose clothes against ultraviolet rays (ultraviolet, UV rays)?

- Thick weave is better than light weave.

- Polyester is better than cotton fabric.

- Dark colors are better than light colors.

- Dry clothes are better than wet clothes.

Always remember to wear a hat to protect your face and scalp from UV rays.

- Some clothes are dyed with special chemicals that absorb ultraviolet rays (the chemical is colorless). Clothing is said to be sun-protective only if the UPF is between 15-50.