UVA vs. UVB
The sun radiates two types of UV rays: UVA and UVB. UVA is associated with skin aging, and UVB is associated with skin burning. Accounting for more than 90% of the UV radiation reaching the Earth’s surface, the UVA light penetrates the skin deeply and holds the bigger responsibility in stimulating premature aging. But that doesn’t mean it’s not central to protect our skin from the UVB light regardless of its superficial penetration into the skin.
It is important to note that while UVB light is blocked by the glass in our homes, UVA light still penetrates, which is why sunscreen should be applied even while staying at home. Also, UV exposure includes the use of tanning beds, UV lamps, and some medicinal treatments for certain skin disorders.
Sunscreen vs. Sunblock
The difference between sunscreen and sunblock translates in the formulation of each product. A sunblock, such as the Sunstop, forms a protective shield on the skin’s surface and reflects the UV rays obstructing them from penetrating the skin altogether. It is usually thick in consistency and has a vivid white color.
Whereas sunscreen penetrates the skin and absorbs the sun rays before it damages the skin and transforms it into heat. It is usually easier to apply because it is thin in consistency and colorless.
SPF vs. Star ratings
Sun Protection Factor (SPF) is a measurement of how long you can stay outside during the day while being shielded from the sun’s burn causing UVB rays.
The star rating ranging from 0 to 5 measures the level of protection from UVA light. The higher the star rating, the better. The best-recommended star rating is 4.
On the other hand, SPF measures how well the sunscreen or sunblock protects the skin from UVB light. It is essential to know that the higher SPF rating does not guarantee higher protection; you will need to reapply it every 2 hours regardless of the SPF value.
As published by the Skin Cancer Foundation, while an SPF of 100 sounds like a lot more than an SPF of 15, SPF 15 screens about 93% of UVB rays while an SPF 30 screens 97%. SPF 50 screens 98%.
How much to apply?
You should use half a teaspoon of sunscreen for your face and neck for sufficient protection. The easiest way to apply the right amount of sunscreen is to use the two-finger rule: squeeze a line all along your index finger and middle finger. It is advised you use the volume of a shot glass to cover the rest of your body’s skin.
Finally, people with skin conditions should avoid products that contain fragrances, preservatives, and para-aminobenzoic acid (PABA).
Protection from the Inside Out
You can protect your body from UV-induced damage not only by wearing a physical sunscreen or sunblock, but also by eating an antioxidant rich diet, including a wide variety of vegetables and fruits, and by supplementing with key antioxidants. It takes at least 8 to 10 weeks to sufficiently protect your skin, if consistent.