The Difference Between Mineral and Chemical Sunscreen
Medically reviewed by Susan Bard, MD
Skin cancer is the most common type of cancer in the United States, and it’s mainly caused by exposure to ultraviolet (UV) radiation from the sun.
According to the American Academy of Dermatology (AAD) nearly 20 Americans die from melanoma—the deadliest form of skin cancer—every single day.
The main thing you can do to minimize your risk of developing skin cancer is to wear sunscreen, which has been proven to reduce the risk of melanoma and other types of skin cancer.
There are several types of UV radiation that can damage your skin:
UVA: UVA rays are primarily responsible for skin aging. There are two types: UVA1 and UVA2.
UVB: UVB rays are what primarily cause sunburn.
UVC: UVC rays from the sun don’t reach the earth. However, artificial light sources, like plant growth lamps and disinfectant lamps, do emit UVC radiation.
Both UVA and UVB rays can be responsible for skin cancer. The best sunscreens provide broad-spectrum protection, which means they block both types.
The American Academy of Dermatology recommends using a water-resistant, broad-spectrum sunscreen of at least 30 SPF, and reapplying every two hours you spend exposed to the sun.
That said, not all sunscreens are created equal. There are two main types—mineral and chemical— and each type has its pros and cons. Here’s what you need to know about both.
SPF stands for sun protection factor. It represents the amount of exposure to UV radiation it takes to get a sunburn while using the product. A higher SPF means more protection against sunburn. Because UVB rays are responsible for sunburns, SPF usually refers to the amount of UVB, not UVA, protection a product provides. This is why it’s important to look for the words “broad spectrum.”
How Mineral Sunscreens Work
UV filters are the ingredients in sunscreen that block the sun’s damaging rays. In mineral sunscreens—also known as physical sunscreens—these UV filters are tiny particles of the metals zinc oxide, titanium dioxide, and sometimes iron oxide.
These particles block UV damage by reflecting or refracting away UV radiation. Research has also shown that, when the particles are small enough, they also work by absorbing UV light.
Mineral sunscreens made with larger particles are more likely to leave a white cast, while smaller particles, called nano-particles, tend to appear more transparent.
Unlike many chemical UV filters, both zinc oxide and titanium dioxide provide broad-spectrum coverage on their own.
Related:The 11 Best Zinc Oxide Sunscreens for Your Face, Recommended by Dermatologists
How Chemical Sunscreens Work
Chemical sunscreens absorb UV radiation and convert it to heat. While mineral sunscreens sit on top of the skin, chemical sunscreen absorbs into it.
Many chemical UV filters block only UVA or UVB rays, which is why chemical sunscreens typically feature multiple active ingredients.
Some of the most common ones include:
Related:Sunscreen vs. Sunblock: What's the Difference, and Which One Is Better?
Which Sunscreen is Better?
Zinc oxide and titanium dioxide are the only two UV filters that are currently classified as safe and effective by the FDA.
A clinical trial published in 2020 found that chemicals from commercially available sunscreens—avobenzone, oxybenzone, octocrylene, homosalate, octisalate, and octinoxate—were found in people’s blood at higher amounts than the exposure threshold recommended by the FDA.
Oxybenzone is part of a group of chemicals called benzophenones. Studies have linked benzophenones to issues like thyroid hormone imbalances in humans. A number of animal studies and some small human studies also point to the ingredient as a hormone-disruptor. But experts say that much more research needs to be done before any conclusions can be made.
Some experts have also flagged octocrylene, because as it degrades, it has been shown to generate benzophenones in sunscreen.
Researchers, the FDA, and the American Academy of Dermatology say it’s still important to wear sunscreen to prevent skin cancer. Ultimately, the best sunscreen is the sunscreen you’ll use, depending on your specific skin and lifestyle needs. If you’re particularly concerned about the ingredients in chemical sunscreens or have sensitive skin, it may be best to try a mineral formula.
Pros and Cons
Tends to have a lighter formula that spreads on easier than mineral sunscreens
Doesn’t leave a white cast
Can cause skin irritation in people with sensitive skin
Takes around 30 minutes for chemical sunscreen to be effective after application
Several of the ingredients in chemical sunscreens have been found to be harmful to coral and other marine life
Mineral sunscreen is less likely to irritate the skin
It works immediately after you apply it
Most mineral sunscreens leave a white cast
In spray or powder forms, there is a risk of inhaling some of the zinc oxide or titanium dioxide particles
Frequently Asked Questions
Which type of sunscreen lasts longer, mineral or chemical sunscreen?
How long your sunscreen is effective depends on factors like if you’re swimming or sweating, how much sunscreen you apply, and how often you reapply. To ensure you’re staying protected, you should apply a shot glass-sized amount of sunscreen to your body and reapply every two hours, or even sooner if you’re doing a lot of swimming or sweating.
Is mineral sunscreen better than chemical sunscreen?
The best sunscreen is the broad-spectrum product that feels best on your skin and works for your needs. However, if you’re concerned about the health implications of chemical sunscreens, you might prefer using a mineral formulation. Zinc oxide and titanium dioxide, which are both used in mineral sunscreens, are the only two ingredients that the FDA currently recognizes as both safe and effective.
A Quick Review
Chemical and mineral sunscreens are two slightly different ways of accomplishing the same goal: to protect against skin cancer and aging.
Mineral sunscreen ingredients like zinc oxide and titanium dioxide are considered safe and effective by the FDA.
Chemical sunscreens have also been proven to block UV rays, but some new research is raising alarm about the potential health effects of chemical sunscreen ingredients like oxybenzone and octocrylene. However, experts say more research needs to be done to provide conclusive evidence that using this type of sunscreen can lead to adverse health outcomes.
Dermatologists and researchers agree that the benefits of using sunscreen greatly outweigh any potential risks.
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