From the Guidelines
Mineral sunscreens are generally considered better than chemical sunscreens for most people, especially those with sensitive skin, due to their ability to provide broad-spectrum coverage and lower risk of skin irritation. Mineral (or physical) sunscreens containing zinc oxide and/or titanium dioxide work by sitting on top of the skin to create a physical barrier that reflects and scatters UV rays away from the skin. They offer immediate protection upon application and are less likely to cause skin irritation, as noted in studies on sunscreen use and skin cancer prevention 1. Chemical sunscreens, which contain ingredients like avobenzone, oxybenzone, and octinoxate, work by absorbing UV radiation and converting it to heat. While chemical sunscreens often feel lighter and blend more easily, they may cause irritation for sensitive skin types, can potentially disrupt hormones, and some ingredients have raised environmental concerns, particularly regarding coral reef damage.
Some key points to consider when choosing a sunscreen include:
- Looking for broad-spectrum mineral sunscreens with SPF 30 or higher
- Applying approximately one ounce (enough to fill a shot glass) to cover exposed areas
- Reapplying every two hours or after swimming or sweating
- Being aware of the active ingredients in sunscreens and trying different products if adverse effects occur, as some ingredients like benzophenone-3 and dibenzoyl methanes have been reported to cause skin irritation 1. Mineral sunscreens have also improved in formulation over the years, with many newer products avoiding the thick, white cast that was once common. Overall, the use of sunscreens, particularly mineral sunscreens, can be an effective measure in preventing skin cancer and reducing the risk of early skin aging, as recommended by the U.S. Food and Drug Administration 1.
From the Research
Comparison of Barrier Mineral Sunscreen and Traditional Chemical Sunscreen
- Barrier mineral sunscreens, which typically contain zinc oxide (ZnO) or titanium dioxide (TiO2), provide a physical barrier against ultraviolet (UV) radiation, whereas traditional chemical sunscreens absorb UV radiation and convert it into heat 2, 3.
- Studies have shown that ZnO and TiO2 are effective in protecting against both UVA and UVB radiation, with ZnO being particularly effective in providing broad-spectrum protection 4, 5.
- Chemical sunscreens, on the other hand, may contain ingredients such as octinoxate and avobenzone, which can be photo-unstable and lose their effectiveness over time 2.
- Some chemical sunscreens have also been reported to cause photoallergy and have endocrine disrupting activity, although large molecular last generation UVB-UVA broad spectrum sunscreens have a better benefit-risk ratio 3.
Safety and Efficacy of Barrier Mineral Sunscreens
- A study published in 2019 found that repeated application of ZnO nanoparticles to human skin did not result in skin penetration or cellular toxicity, suggesting that ZnO-based sunscreens are safe for use 4.
- Another study published in 2000 found that ZnO and TiO2 were effective in providing broad-spectrum protection against UVA and UVB radiation, and that the critical wavelength value, which measures the wavelength at which 90% of the integral of the spectral absorbance curve is reached, was a useful indicator of broad-spectrum protection 5.
- The American Journal of Clinical Dermatology published a review in 2017 emphasizing the importance of broad-spectrum protection and the benefits of sunscreen use, including prevention of photocarcinogenesis and photoaging 6.
Key Differences Between Barrier Mineral and Chemical Sunscreens
- Barrier mineral sunscreens provide a physical barrier against UV radiation, whereas chemical sunscreens absorb UV radiation and convert it into heat 2, 3.
- Barrier mineral sunscreens are generally considered to be safer and more effective than chemical sunscreens, although chemical sunscreens may be more cosmetically appealing 3, 4.
- The choice between barrier mineral and chemical sunscreens ultimately depends on individual preferences and needs, although barrier mineral sunscreens are generally recommended for their safety and efficacy 6, 5.