One of the most common questions is “Do I need to apply sunscreen even if I don’t go outside?” The answer is yes and the reasons are described here.
How does the sun affect the skin?
The sun provides light and heat to allow us to live. The light emitted from the sun has many different colors or wavelengths, some of which are harmful to the skin. Specifically, UV rays (or ultraviolet rays) damage the skin over time. When UV rays reach the skin, they cause changes in the skin. The cells in the skin produce something called free radicals. Free radicals lead to a number of changes in the skin. They damage and degrade collagen, the protein in the skin that keeps the skin tight, firm, and youthful. As a result, the skin becomes loose and saggy and fine lines, wrinkles, and enlarged pores are seen. Another change is the formation of dark discolorations, sometimes called sun spots. The harmful free radicals stimulate the skin to form these unsightly dark spots. Other effects include thinning of the skin, decreasing the skin’s protective barrier function, and leading to the formation of broken capillaries or generalized redness. In order to prevent all of these changes it is important to protect ourselves from the harmful UV rays.
What sunscreen should I use?
Dr. Alex recommends using a sunscreen with an SPF of at least 30 every day. Also make sure it has broad spectrum (or UVA and UVB) protection. Ingredients such as zinc oxide and titanium dioxide provide such protection. If outdoors for long periods, reapply sunscreen every one to two hours. Also reapply if your skin gets wet such as when swimming. Avoid direct sun exposure and try to stay in the shade as much as possible when outdoors, especially during the middle of the ray when the UV rays are the strongest.
When should I apply sunscreen?
Many people feel that it is only necessary to apply sunscreen when doing certain activities such as going to the beach. But exposure to harmful UV rays occurs even with short exposure to the sun such as going outside to get the mail. It is also important to understand that the temperature is not related to the amount of UV rays. For example, although it may be cold in the winter months, there is still sun exposure so it is important to apply sunscreen during all four seasons. At the same time rainy weather does not block all UV rays. Many people do not apply sunscreen when it is overcast or raining. However, the harmful UV rays can penetrate the clouds and still damage the skin. Therefore, it is important to apply sunscreen on rainy days too. Also, UV rays penetrate through glass such as car windows and windshields. Although not technically outside when driving, you are getting exposure when driving. Additionally, many people work in offices where sunlight enters through windows, exposing them to harmful UV rays.
So even though you may think you’re not outdoors, you are still getting a lot of sun exposure. Over years, this exposure to harmful UV rays damages the skin, leading to changes associated with aging such as fine lines, wrinkles, uneven color, and redness. Applying sunscreen every day will prevent these changes.