Everything You Need to Know About Sunscreen

Most people know that sunscreen is the best way to avoid sunburn, long-term sun damage, and skin cancer. That said, knowing what a high-quality sunscreen must contain, how often and how much to use, and other important details is just as important.

Talented dermatologist Dr. Latha Vellanki has dedicated her career to helping patients look and feel their best, from providing skin-beautifying aesthetic treatments to screening for and treating skin cancer. The entire team at Helena Dermatology and Montana Aesthetics, PC, is also dedicated to your health. 

When Dr. Vellanki talks to you about caring for your skin, preventing sun damage will definitely be covered, and that’s when she touches upon the importance of daily sunscreen use. 

How UVA and UVB rays damage your skin

In the days before sunscreen, all people could do was cover up with clothing or sit under beach umbrellas, but much less was known then about how much harm sun can cause to your skin. Learning about the sun’s rays is critical to understanding the importance of sunscreen.

The two types of sun rays that sunscreen protects against are UVA and UVB rays. UVA rays penetrate your skin more deeply than UVB rays and even penetrate windows. Unlike UVB rays — 95% of which are absorbed by our ozone layer — all UVA rays reach your skin. 

Even so, the 5% of UVB rays that get to your skin are quite damaging to your outer skin layers. UVB rays are responsible for sunburn, and are also the primary culprits that cause skin cancer. Both UVA and UVB rays damage your DNA in different ways and age your skin prematurely. 

How sunscreen protects your skin

The earliest modern form of a sun-protective product was developed in Europe in the 1930s, but the advent of what we now know as sunscreen really started in the 1960s. Two types of sunscreens evolved. 

Chemical sunscreens contain chemicals that actually absorb UV rays, so your skin doesn’t. Physical sunscreens place an impenetrable protective layer between your skin and the sun. When UV rays reach the minerals in these sunscreens, the rays are bounced back and are prevented from reaching your skin. 

An example of this type of sunscreen is the zinc oxide that used to be “standard issue” for lifeguards. Now chemical sunscreens do the same thing, but are invisible once rubbed into your skin. 

All sunscreens are not created equal

When you purchase sunscreen at the store, make sure the label lists these attributes:

  • Is broad-spectrum — blocks UVA and UVB rays
  • Lists zinc oxide and titanium oxide in the ingredients if choosing a physical sunscreen
  • Has a high sun protection factor, or SPF number of at least 30

When you’ve chosen a high-quality sunscreen, it’s essential that you reapply it every two hours and even more often if you’re swimming or playing sports that cause you to perspire. It’s also best to avoid being in direct sun during the window of time when its rays are most powerful, which is between 10am and 4pm. 

Other important sunscreen facts

Patients often ask Dr. Vellanki if it’s only important to wear sunscreen for a day at the beach or pool. Her answer is an emphatic “No!”  

Since a staggering 1 in 5 Americans are predicted to be be affected by skin cancer, daily sunscreen use is a must, and it’s best to apply enough, usually an amount that would fill a shot glass, to your skin 15 minutes before you go outside. 

There are some areas of your body that are easy to forget about when it comes to your daily slathering too, so don’t forget the tops of your ears, the areas behind your knees, and even your scalp. 

Complement your sunscreen use with other sun-smart practices, like sitting in the shade, wearing clothing that’s specifically sun-protective, and donning a hat and sunglasses. 

Learn why it’s life-saving to protect yourself from the sun

Find out more about how you can protect your skin now and avoid skin cancer later. Call our office to schedule a consultation with Dr. Vellanki, or use our convenient online request tool.  

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