Does Sunscreen Truly Matter?

Is it really necessary to wear sunscreen every day? The answer is YES. We need to use sunscreen every day, rain or shine (and winter or summer), in order to protect our skin cells from ultraviolet (UV) exposure. UV rays can damage the skin and cause damage to your cell’s DNA, causing mutations to occur. These mutations can lead to cancer.

 We are exposed to two types of ultraviolet light on a daily basis: UVA and UVB. UVA has a longer wavelength and less energy that UVB. However, these rays exist during the day and night and play a significant role in aging. UVA rays have been associated with causing fine lines, wrinkles, loss of elasticity and hyperpigmentation.  These rays can pass through glass (think your car window) and may be present in fluorescent lights (what’s that above your cubicle?). Prolonged exposure to UVA will damage your skin and will even show up years after the exposure takes place. UVB are the “burning” rays which are present during the day (even on cloudy days!).

So, what is the best sunscreen for protection? To answer this question, you need to be aware of the active ingredients in your sunscreen. For example, a sunscreen with both UVA/UVB protection which also includes antioxidants can help prevent future damage as well as assist the skin in repairing itself.

Sun Protection Factor (SPF) is the multiple of time it takes for your skin to burn. For example, if it normally takes you 10 minutes to burn, and you use an SPF 15, you should not burn for 150 minutes (10 x 15). Bear in mind that SPF only applies to UVB rays and not UVA rays. FDA has specific labeling requirements for UVA protection.

Some of the most common chemicals used in sunscreens are oxybenzone, octyl methoxycinnamate, and avobenzone. These chemicals work by absorbing UVB light. However, they can only absorb UVB light until they become saturated. Once they become saturated, they lose their ability to protect. This is why we have to reapply sunscreen often, especially after prolonged sun exposure or swimming. These chemicals are great for protection against UVB light, but cannot protect us from UVA light. Remember that UVA light penetrates deeper into the skin, affecting collagen, elastin, and DNA. So, what can protect us from UVA light?

Titanium Dioxide and Zinc Oxide work as a sunscreen by reflecting the ultraviolet light, including UVA (think thick, white goop on a lifeguard’s nose). Micronized versions of Titanium Dioxide and Zinc Oxide are now used and can even be found in some makeup formulations. These “physical” sunscreens are inorganic and generally do not produce sensitivity reactions, as a chemical sunscreen might.

Do you think it is more effective to use an SPF 50 sunscreen rather than an SPF 30 sunscreen? The answer is- it depends. Most sunscreens with an SPF of 30 absorb about 94% of UVB light. Increase that SPF to 50, and you increase the protection to 99%. That sounds good, right? By increasing the absorption power to SPF 50, you are also increasing the amount of potentially irritating chemical ingredients by 50%. For those with sensitive skin, this increase in irritants may be more of a risk than the extra SPF protection provided.

The bottom line is- sunscreen does matter. Whether you use absorbers or reflectors, UVB or UVA protection, you actually have to use them for any of them to work! It also doesn’t hurt to limit your sun exposure.