Does sunscreen prevent tanning? The health risks of tanning

The general guideline that there is no such thing as a safe tan does not directly answer the question "does sunscreen prevent tanning?" Sun care can protect your skin from severe UV-ray damage, but sunscreen alone does not prevent your skin from gradually developing a tan. It’s important to use a sufficient level of SPF (at least 30), reapply often, and limit your sun exposure. Read on to learn our two-fold approach to protecting your skin from the sun’s harmful rays. 

Does sunscreen prevent tanning?

Using sunscreen as directed makes it possible to stay in the sun for longer before developing a sunburn. Sun protection factor (SPF) ratings refer to the duration of time that sunscreen protects skin from burning relative to skin exposure to direct sunlight without a preventative layer. For example, an SPF 30 formula indicates that it will take 30 times longer for your skin to burn than it would without sunscreen that has this rating.

The stated level of protection for sunscreen only applies when you use a sufficient amount of product. You should also completely reapply sun protection every two hours (and  more frequently if you are sweating or swimming outdoors). Make sure that every part of exposed skin is completely covered with a generous coating of mineral or chemical sunscreen to prevent sunburns and slow the rate of tanning.

SPF ratings also indicate the percentage of ultraviolet rays that sunscreen blocks. Sunscreen rated SPF 30 absorbs or reflects about 97% of UVB rays. This means that a little over 3% of UV rays can still pass through the protective coating and tan exposed skin over time. The best answer to the question "does sunscreen prevent tanning" is that preventative formulas significantly slow the rate at which tanning takes place. If you’re going to be in the sun, combining sunscreen with protective clothing is the best way to minimize the effects of sun exposure.

How does sun exposure cause tanning?

When UV light makes contact with skin, it causes the production of the pigment called melanin to increase. Any amount of tanning indicates sun damage. The Fitzpatrick classification of skin types is used to assess the risk for sun damage. Here are the six types or shades of skin according to this system:

• Type I Skin: Very light skin tones that burn without tanning.
• Type II Skin: Fair skin tones that tend to burn before tanning.
• Type III Skin: Medium skin tones that develop mild burns and have an average propensity to tan.
• Type IV Skin: Light brown skin tones that rarely burn and are likely to tan.
• Type V Skin: Brown skin tones that are unlikely to burn and are prone to tanning.
• Type VI Skin: Dark skin tones that do not burn but tan easily. 

Skin types and tones determine how prone skin is to tanning, and how likely you are to develop sunburn or erythema (a reddening of the skin, usually in patches, that causes dilation of the blood capillaries). Using sunscreen according to the directions reduces your risk of severe sun damage, but your skin may still develop a visible tan depending on your skin tone.

You can get a better answer to the question "does sunscreen prevent tanning" by factoring in your skin type, your sunscreen’s SPF and the duration of direct sun exposure. Regardless of your skin tone, use a broad-spectrum sunscreen with an SPF rating of 30 or higher to limit exposure to ultraviolet rays, and wear UPF accessories and clothing to prevent skin damage associated with tanning.

What are the health risks associated with tanning?

One of the reasons that many people ask "does sunscreen prevent tanning" is to determine whether sun care prevents damage to skin. While sunburns indicate more severe skin damage than tanning, both result from injury to the DNA in skin cells. 

Indoor tanning is not a safe alternative to sun exposure. According to the Skin Cancer Foundation, even a single indoor tanning session prior to age 35 increases risk factors for developing melanoma by as much as 75%. The tanning process is a response to genetic damage to cells on the outermost layer of your skin. Melanin oxidizes as it migrates closer to the skin surface, which visibly darkens skin. Damage to these cells does not reverse as a tan fades but is cumulative over the course of a lifetime.

Can the sun damage your skin even if you don’t get a tan?

Sun damage is most pronounced on Type I skin, which is very fair and burns without tanning. People who have this skin type should always use sunscreen with a high SPF, as their skin is prone to severe sun damage. Any direct sun exposure, especially over prolonged periods of time, can damage skin of any tone or type.

It’s a common misconception that tanning increases skin’s resilience to sun exposure. A tan provides the equivalent of SPF 2-4, which is not sufficient to prevent UV damage with or without sunscreen. You should always use preventative sun care when spending time outdoors, but dermatologists also recommend wearing sunscreen indoors—such as when you’re near windows or driving during daylight hours. Glass windows block most UVB rays (the primary cause of sunburns), but more than 50% of UVA rays can pass through glass and damage skin.

UVA rays transmitted through the windows of your home, vehicle, or workplace can penetrate your skin. Wearing broad-spectrum sunscreen whenever you’re within several feet of a window can prevent damage caused by sun exposure.

How can you protect your skin from the sun?

One of the best ways to protect your skin from photodamage is to use sunscreen with a sufficient SPF rating. While sunscreen with an SPF rating of 30 is about 97% effective at blocking UVB rays, an SPF 45 formula can block at least 97.8% of UVB rays and an SPF 50 sunscreen can block at least 98% of UVB rays. Even when you use sunscreen with these ratings as directed, anywhere from 2% to 3% of UVB rays can still damage exposed skin.

Although the difference between the 3% of UVB rays that pass through SPF 30 and the 2% of UVB rays that pass through SPF 50 seems minor, SPF 30 actually allows about 50% more UV radiation to penetrate the skin than SPF 50. A sunscreen with a rating of SPF 40 or higher provides significantly more protection against tanning than a formula with a lower SPF. For the most protection against sun damage and tanning, select a broad-spectrum sunscreen with a high SPF. (That said, there’s no real need to go above SPF 50, and regardless of which SPF you choose, you should still reapply at least every two hours.)

It’s important to understand that tanning can still occur over time, even when you wear sunscreen every day. Accessories and clothing with an Ultraviolet Protection Factor (UPF) rating can further reduce cumulative exposure to UV rays that tan the skin. Materials with a UPF rating of 50 block 98% of UV light. Wearing densely woven materials and sunscreen is the best way to keep your skin from producing melanin as a protective response to sun exposure.

When should you apply sun protection?

The American Academy of Dermatology recommends applying sunscreen prior to going outdoors or in advance of exposure to the sun indoors through a window. Dermatologists recommend applying mineral or chemical sunscreens at least 15 minutes before exposing skin to sunlight to give any formula time to dry and create a uniform protective film over the surface of your skin.

Reapply sunscreen at least every two hours during continuous sun exposure, or more frequently when you are sweating or swimming. Clair Obscur is developing sunscreen with a unique, patent-pending applicator that features a convenient design small enough to take everywhere. It allows for mess-free use at any time to provide consistent protection. Carry sunscreen in your bag or keep it at work to ensure that your skin stays protected all day, every day.

It is a good idea to get in the habit of wearing sunscreen every day. Exposure to ultraviolet rays can occur any time you venture outdoors, even if you don’t plan to stay in the sun for a long time. Your skin can sustain damage during short trips to and from your vehicle, while driving during the day, or when you’re inside near uncovered windows. Make sure to apply sunscreen to any exposed skin, including your face, hands, and arms.

Does sunscreen prevent tanning and related health risks?

Sunscreen prolongs the amount of time it takes for ultraviolet rays to damage skin. For instance, when applied (and reapplied) properly, an SPF 50 formula will protect skin 50 times longer than skin that has no sunscreen. Skin may still become tan over time, even while using proper sun care, which is why you should take additional preventative measures against sun damage.

The best way to minimize sun-related skin damage is to limit direct exposure to sunlight between the hours of 10 a.m. and 4 p.m. If you plan to be outdoors, try to stay in the shade as much as possible. For more sun protection, wear a brimmed hat, headscarf, rashguard or other UPF-rated clothing. 

Tanning can still occur when using sun protection and is a sign of potential sun damage. Sunscreen extends the duration of sun exposure that skin can sustain prior to developing a sunburn based on the SPF rating and your skin type. Clair Obscur is developing a variety of sun protection solutions to shield your skin from cumulative sun damage; sign up for our mailing list to be first in line.