Sun Protection

Mineral v.s. Chemical Sunscreens

Summer is marked by good weather and lots of time spent outside. To keep enjoying the outdoors during the summer, it is important to practice proper sun protection that will prevent adverse effects caused by overexposure to the sun. Not only can the sun cause painful In fact, any darkening in natural skin color, this includes a suntan, is considered skin damage.

Although the sun’s rays are most powerful on bright, summer days, it’s a misconception that sun protection is only for the summer months. Sunlight contains two types of radiation that are damaging to the Sun protection should be a consideration all year round.

Sunscreen usage is key to a good sun protection regime, especially when the skin will be exposed directly to sunlight. However, sunscreen should not be the only part of the regime, other crucial protection measures include the following:

Staying in the shade
Avoiding the sun during mid-day when sun rays are most intense
Covering the skin with clothing (you can purchase clothing with an Ultraviolet Protection Factor (UPF))
Wearing a hat

How does sunscreen protect you from the sun?

There are two types of sunscreens: mineral sunscreens, also known as physical sunscreens, and chemical sunscreens. The two types differ in their active ingredients and the method in which they protect your skin.

In recent years there has been concern about some of the chemicals found in chemical sunscreens. Oxybenzone and octinoxate have been banned in Hawaii due to their damaging effect on marine ecosystems. No scientific evidence exists that the ingredients in chemical sunscreens pose a risk to human health, but if chemical sunscreen makes you nervous, do not skip the sunscreen, use mineral sunscreen instead.

Mineral Sunscreen

Mineral sunscreens contain active ingredients such as titanium dioxide and zinc oxide. They reflect UV rays and prevent UV from reaching the skin. They offer immediate protection - no wait time necessary. This type of sunscreen is not absorbed into the skin, rather it sits on the top layer of the skin and provides a physical barrier from the sun. For this reason, it can be hard to fully rub in and leaves a white cast on the skin. This issue can be partly mediated if you use a tinted mineral sunscreen. Mineral sunscreens tend to rub off quicker than chemical sunscreens, and therefore may require more frequent reapplications. Since mineral sunscreens tend to be non-irritating, they are the preferred sunscreen type for individuals with sensitive or acne-prone skin.

Chemical Sunscreen

Chemical sunscreens soak up UV rays and convert them into non-harmful heat rays, which are then emitted by the skin. Since this type of sunscreen is absorbed by the skin, it tends to be easier to rub in and is less likely to leave a white residue as compared to mineral sunscreens. It is recommended that you wait 10-15 minutes after the application of a chemical sunscreen before going out into the sun. Chemical sunscreens require this time to absorb into the skin and begin to offer full protection. The active ingredients found in chemical sunscreens tend to be harsher on the skin as well as eyes and may clog pores. In addition, since chemical sunscreens emit heat from the face, they are not recommended for individuals with rosacea as heat can aggravate this condition.

Who Needs Sunscreen?

Everyone needs sunscreen, regardless of skin tone or sex. Melanin (skin pigment) offers a natural sun protection factor (SPF); and although darker skin tones are naturally more protected from sun damage than lighter skin tones, the SPF is low and does not eliminate the risk of skin damage nor the need for sunscreen. Moreover, certain medications and products, for example benzoyl peroxide and antibiotics, may cause sensitivity to sunlight and make sunscreen usage even more crucial. The only group of people who should not wear sunscreen are babies under 6 months of age because of their extremely sensitive skin. Infants under 6 months should avoid the sun.

Best Sunscreen Practices

If you have sensitive skin, choose a mineral sunscreen instead of a chemical sunscreen
If you are using a chemical sunscreen, wait 10-15 minutes after applying before stepping out into the sun
Select a sunscreen that is broad-spectrum (i.e., provides both UVA and UVB protection)
Choose a sunscreen that has an SPF 30 or higher
Reapply sunscreen every 2 hours or more frequently if you are swimming and/or sweating
Apply enough sunscreen (45 ml for the entire body, 10 ml of which should be applied to the face and neck)

References

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