Can Sunscreen Stop You from Tanning? A Dermatologist Weighs In

There are plenty of myths about tanning, such as needing a "base tan" or having to burn first. But one question often lingers—does sunscreen really stop you from tanning? You might have observed that your skin still darkens during the summer, even when you’ve applied sunscreen to your face and body before stepping outside.

The reality is, even with thorough application of high SPF sunscreen, tanning can still occur. Often, this happens due to a common mistake: improper use of sunscreen. To understand how sunscreen works effectively, we spoke with a dermatologist to break it all down.

How Sunscreen Functions and Whether Tanning Is Possible

You might be wondering: Doesn’t sunscreen stop tanning and sunburns? The truth is, when sunscreen is used properly and reapplied every two hours or after sweating or swimming, it greatly lowers the risk of tanning or burning.

That said, tanning can still happen for several reasons. “Sunscreen works by either blocking (in the case of mineral sunscreen) or absorbing (in the case of chemical sunscreen) UV rays, which cause tanning and burns,” says dermatologist Heather D. Rogers, MD. “But no sunscreen offers complete protection, and some UV rays can still get through.”

“More time in the sun means more UV rays hitting your skin, which boosts melanin production—the pigment that gives skin its color,” Rogers explains. This increase in melanin results in a tan.

In short, while using sunscreen correctly greatly reduces sun damage, it’s not a perfect shield. This is why additional measures like wearing sun-protective clothing, hats, sunglasses, and staying in the shade can further minimize UV exposure.

If you find yourself tanning despite applying SPF generously, here are some possible reasons:

• Incorrect Application: One of the main reasons for tanning or burning is improper sunscreen use. “To get the full SPF protection, you need to apply enough sunscreen,” says Dr. Rogers. She suggests using roughly two tablespoons to cover your entire body, including your face, ears, neck, feet, and scalp.
• Not Reapplying Enough: Sunscreen should be reapplied every two hours, or more often if you’re sweating or swimming.
• Low SPF Level: Not all sunscreens offer the same protection. Ensure you’re using a broad-spectrum sunscreen that guards against both UVA and UVB rays. Most modern sunscreens are broad-spectrum, but always verify. Also, opt for SPF 30 or higher.
• Expired Sunscreen: Yes, sunscreen has an expiration date! Make sure you’re not using it past its “best by” date.
• Incompatible Products: Sunscreen can clash with other ingredients. Avoid layering silicone-based products, applying SPF over oils, or mixing sunscreen with lotions, oils, or foundations.
• Extended Sun Exposure: Even the best SPF isn’t 100% effective. Wear hats, use a sun umbrella, stay in the shade, and avoid being outdoors during peak sunlight hours when possible.

How Does the SPF Rating Affect Tanning?

SPF, or Sun Protection Factor, is a rating found on all sunscreens. It measures how well the product protects your skin from the damaging effects of ultraviolet rays.

But what does the SPF number really mean? Here’s an explanation:

• SPF 15 filters out 93.3% of UV rays
• SPF 30 filters out 96.7% of UV rays
• SPF 45 filters out 97.8% of UV rays
• SPF 50 filters out 98% of UV rays

What about higher SPFs? The truth is, SPF values above 50 don’t offer significantly more protection. No sunscreen can block 100% of UV rays; 98% is the maximum protection achievable.

While higher SPF ratings mean better protection against sunburn, no sunscreen can completely stop UV rays. Tanning can still happen with sunscreen on, but it will take longer to develop.

Why Tanning Is Never Safe

Despite popular beliefs about “base tans” or the appeal of a sun-kissed glow, there’s no safe way to tan. The key takeaway is that even if your skin isn’t burning, UV exposure is still causing DNA damage to your skin cells.

“Tanning occurs when UV radiation from the sun or tanning beds damages the DNA in skin cells,” Rogers explains. “Even without visible burns, a tan signals skin damage, as the skin produces pigment to protect itself from further harm.”

She emphasizes that repeated skin damage is dangerous for all skin tones. It accelerates aging—causing wrinkles, sunspots, and sagging—and, more critically, raises the risk of skin cancer.

If you enjoy a sun-kissed look, try a professional spray tan, at-home sunless tanners, a tinted sunscreen for a subtle glow, or bronzers.

Frequently Asked Questions

• Is a tan as harmful as a sunburn?

  Despite common misconceptions, a tan can be just as damaging as a sunburn (even if it feels less severe). Both result from UV ray damage, so while a tan may appear healthier, both harm your skin. UV rays damage DNA and increase skin cancer risks, so it’s best to use sunscreen, cover up, or avoid sun exposure.

• Does sunscreen prevent your body from producing vitamin D?

  In short, no. Research shows that sunscreen use doesn’t significantly lower vitamin D levels. However, studies have focused on lower SPFs, and there’s limited data on high SPFs. Experts agree that even if sunscreen slightly reduces vitamin D production, its sun protection benefits far outweigh any drawbacks.

• Can you wear sunscreen in a tanning bed?

  Yes, you should wear sunscreen in a tanning bed. However, doctors advise avoiding tanning beds entirely due to their health risks. Alternatives like self-tanners or spray tans are safer. But if you use a tanning bed, sunscreen can help prevent burns.