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Sunscreen
Sunscreen (also known as sunblock) is a lotion, spray or other topical product that helps protect the skin from the sun's ultraviolet (UV) radiation, and which reduces sunburn and other skin damage, ultimately leading to a lower risk of skin cancer.
The best sunscreens protect against both UVB (ultraviolet radiation with wavelength between 290 and 320 nanometres), which can cause sunburn, and UVA (between 320 and 400 nanometres), which damages the skin with more long-term effects, such as premature skin aging. Most sunscreens work by containing either an organic chemical compound that absorbs ultraviolet light (such as oxybenzone) or an opaque material that reflects light (such as titanium dioxide, zinc oxide), or a combination of both. Typically, absorptive materials are referred to as chemical blocks, whereas opaque materials are mineral or physical blocks.
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July 8, 2026
July 8, 2026 Scientists have discovered that creatine may strengthen one of the immune system's most important cancer-fighting pathways by energizing dendritic cells that activate killer T cells. The promising results could eventually help make immunotherapy ...
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July 7, 2026 Scientists at the University of Illinois Chicago have turned an unlikely source into a potential new weapon against cancer: bacteria that naturally live inside tumors. They developed a peptide called aurB, inspired by a bacterial protein, that ...
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July 7, 2026 Scientists have identified a molecular switch that may help explain how colorectal cancer becomes deadly. When levels of a gene-regulating factor called GATA6 drop, cancer cells can shed their normal identity and transform into highly adaptable, ...
July 6, 2026 Researchers have uncovered a molecular “switch” that helps explain why exercise keeps aging muscles healthy. By reducing levels of a gene called DEAF1, physical activity allows older muscles to clear out damage, repair themselves, and maintain ...
July 6, 2026 Scientists have finally solved a nearly 30-year-old mystery surrounding two unusual molecules found in rye pollen that once showed an intriguing ability to help animals fight tumors. By determining ...
July 6, 2026 Scientists are calling for a lunar quarantine facility where samples from Mars, the Moon, and beyond would be examined before being brought to Earth. They warn that even a tiny alien microorganism ...
July 6, 2026 A new study suggests that apoB, a blood test that measures harmful cholesterol particles, is better than standard LDL cholesterol testing for deciding who needs more intensive treatment. Researchers found it could prevent more heart attacks and ...
July 6, 2026 A large study found that pregnant women are exposed to dozens of common chemicals, many of which were associated with earlier births and lower birth weights. Researchers also discovered that some ...
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July 7, 2026 A new study suggests human hair grows in a way scientists never expected. Researchers found that hair is pulled upward by coordinated cell movements inside the follicle rather than simply being ...
July 5, 2026 Researchers have identified a previously overlooked mechanism of brain cell death that appears to play a major role in Alzheimer's disease and frontotemporal dementia. The finding could lead to new ...
July 5, 2026 Quantum mechanics has journeyed from a strange and controversial idea to the foundation of some of humanity’s most advanced technologies. Now researchers are pushing its boundaries even further, ...
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July 5, 2026 Some cancer cells evade treatment by entering a dormant state triggered by stress hormones. ETH Zurich scientists have created a light-controlled molecular switch that selectively destroys the ...
July 4, 2026 Some people live past 100 with remarkable health, and researchers may have uncovered one reason why. A new study found that centenarians have a unique chemical "fingerprint" in their blood that sets ...
July 4, 2026 A UCLA study has identified a hidden Achilles' heel in aggressive small cell cancers that have resisted new treatments for decades. Scientists found that tumors lacking the RB gene become critically ...
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