The Importance of Sun Protection

The primary stressor for inflammation-based conditions like photoaging, rosacea, acne, and hyperpigmentation is—you guessed it—sun exposure. Here are the most common sun traps and how to avoid them.

First things first---how to apply it? And reapply it? When it comes to sun protection being safe is better than being sorry, so I always error on the side of caution. With that said, I follow the quarter sized amount for your face (yes, literally a quarter!) and a shot glass full of SPF for face, neck, and décolleté. I usually put on a half quarter sized amount on first, by patting the SPF into my skin as opposed to rubbing it in, and then after that first round is all dried down, I put on the second half quarter. Usually, while letting my first SPF application dry I'll brush my teeth or start a load of laundry. It's also imperative to allow your SPF to fully dry down before putting on any makeup or going outside. The easiest reapplication I've found is to use a SPF powder.

Okay, now let's breakdown why sun protection is so very important.

Photoaging and UV exposure

UVB—Burning rays which penetrate to the epidermis cause redness, damage DNA and are linked to squamous and basal cell carcinomas. At their peak between 10am to 4pm, UVB rays reflect off shiny surfaces, making snow, sand and water excellent sunburn accelerators.

UVA—Aging rays penetrate to the dermis and cause wrinkles by cross-linking collagen and elastin, and hyperpigmentation because they turn melanin darker. Present from sunup to sundown, they penetrate clouds and glass.

Tips

1. Always wear sunscreen, SPF 30, rain or shine.

2. The standard sunscreen reapplication rule is every two hours. A little-known but true factoid is that this rule exists not because you sweat or wash it off after a certain amount of time, but because chemical sunscreens have a habit of degrading in the sunlight. 

Rosacea and UV exposure

Rosacea involves a complex interaction of different factors and pathways leading to a chronic inflammatory and vascular response. A major instigating factor is UVB/ UVA exposure.

UVB rays penetrate to the epidermis and increase secretion of two factors: vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF2). These increase vascularization of the skin and cause swelling.

UVB triggers activation of vitamin D3 which directly induces the expression of cathelicidin. Cathelicidin is an antimicrobial peptide that, when processed by rosacea-type skins results in vasoactive and pro-inflammatory peptides and peptide fragments.

UVA and UVB—UV also produces reactive oxygen species (ROS), which cause dermal damage by stimulating enzymes, these enzymes break down collagen in the dermal matrix. A damaged dermal matrix may accumulate inflammatory mediators causing a retention of inflammatory cells.

Tips

Many people with rosacea simply do not tolerate sun very well at all and are advised to limit their sun exposure. However, because most of us like a little sun, these suggestions will help boost your tolerance.

  1. Wearing a zinc oxide sunscreen is very important for rosacea-prone people. Because sun damage continues even after the sun is no longer working directly on your skin, and because zinc oxide is a wonderful anti-inflammatory.

  2. Take a high quality vitamin D3 with K2 supplement.

  3. Take antioxidant supplements, especially astaxanthin and lycopene. These antioxidants from the carotenoid family will increase your tolerance to the sun. Retinoids help with inflammation by reducing signals that trigger cathelicidin production. Use a retinol or retinoid product at night. Always be sure to wash your face in the morning and be vigilant about applying SPF.

Hyperpigmentation and UV Exposure

UVB stimulates melanin biosynthesis (aka burning ray)

UVA turns melanin darker (aka aging ray)

Tips

  1. Remember that UVA rays penetrate glass and clouds and are always present. Wear zinc oxide sunscreen every day, rain or shine.

  2. If you are taking medications, check to see if photosensitization or hyperpigmentation are side effects.

  3. Avoid skin-bleaching ingredients like benzoyl peroxide and hydroquinone. They are well-known photosensitizers and may increase your hyperpigmentation.

  4. Avoid fragrances and essential oils that may cause photosensitivity: especially oil of bergamot, lemon, lemongrass, jasmine absolute and musk amber.

  5. Don’t get too hot—heat stimulates melanin production, so if you exercise in the sun, be sure to take breaks to cool down.

Miranda Rojas