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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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Health & Medicine News
February 7, 2026
Feb. 7, 2026 New research suggests the astringent sensation caused by flavanols could act as a direct signal to the brain, triggering effects similar to a mild workout for the nervous system. In mouse experiments, flavanol intake boosted activity, curiosity, ...
Feb. 7, 2026 New simulations reveal that both H1N1 and COVID-19 spread across U.S. cities in a matter of weeks, often before officials realized what was happening. Major travel hubs helped drive rapid nationwide transmission, with air travel playing a bigger ...
Feb. 7, 2026 A major study suggests menopause is linked to changes in brain structure, mental health, and sleep. Brain scans revealed grey matter loss in areas tied to memory and emotional regulation, while many women reported increased anxiety, depression, and ...
Feb. 7, 2026 For decades, Americans were surrounded by lead from car exhaust, factories, paint, and even drinking water, often without realizing the damage it caused. By analyzing hair samples preserved across generations, scientists uncovered a striking record ...
Feb. 6, 2026 New research suggests that Epstein-Barr virus may actively provoke the immune system in people with multiple sclerosis. Scientists found large buildups of virus-targeting immune cells in the nervous ...
Feb. 6, 2026 Researchers have discovered a previously unknown enzyme that plays a crucial role in fat production. By blocking it, they stopped weight gain, reduced liver damage, and lowered harmful cholesterol levels in animal studies. The finding opens the door ...
Feb. 6, 2026 Colorectal cancer has long baffled scientists because, unlike most tumors, patients often do better when their cancers are packed with immune-suppressing regulatory T cells. New research finally explains why. Scientists discovered that these T cells ...
Feb. 6, 2026 Scientists at Keck Medicine of USC are testing an experimental stem cell therapy that aims to restore the brain’s ability to produce dopamine, the chemical whose loss drives Parkinson’s disease. The early-stage clinical trial involves implanting ...
Feb. 6, 2026 New research using rhesus monkeys suggests that the brain’s relationship with alcohol may begin forming long before a person ever takes a drink. Scientists found that exposure to alcohol before birth reshaped the brain’s dopamine system, a key ...
Feb. 6, 2026 Scientists in Australia have uncovered a clever new way to fight some of the most dangerous drug-resistant bacteria by targeting a sugar that exists only on bacterial cells. By designing antibodies that recognize this unique sugar, researchers were ...
Feb. 6, 2026 A new imaging breakthrough combines ultrasound and light-based techniques to generate vivid 3D images that show both tissue structure and blood vessel activity. Developed by researchers at Caltech and USC, the system delivers detailed results ...
Feb. 5, 2026 Researchers have figured out how psoriasis can quietly turn into joint disease for some patients. Immune cells formed in inflamed skin can travel through the blood and reach the joints, where they sometimes trigger inflammation. The key difference ...
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Feb. 5, 2026 People who switch to a fully unprocessed diet don’t just eat differently—they eat smarter. Research from the University of Bristol shows that when people avoid ultra-processed foods, they ...
Feb. 5, 2026 Kidney disease often creeps in silently, and many patients aren’t diagnosed until major damage is already done. New research shows that even “normal” kidney test results can signal danger if ...
Feb. 5, 2026 Researchers have created the first complete map showing how hundreds of mutations in a key cancer gene affect tumor growth. By testing every possible mutation in a critical hotspot, they found that ...
Feb. 5, 2026 Advanced care provided by air ambulance teams was linked to higher survival rates in major trauma patients. Researchers found that more people survived than predicted by standard models, including ...
Feb. 5, 2026 As bird flu continues to circulate in animals and spill over into humans, researchers are racing to stop it before it adapts to spread widely between people. A new nasal spray vaccine showed strong ...
Feb. 4, 2026 Popular weight-loss drugs like Ozempic and Wegovy can dramatically curb appetite, but experts warn many users are flying blind when it comes to nutrition. New research suggests people taking these ...
Feb. 4, 2026 A massive Swedish study tracking nearly 28,000 people for 25 years found an unexpected link between full-fat dairy and brain health. Among adults without a genetic risk for Alzheimer’s, eating more ...
Feb. 4, 2026 Scientists are digging into why heart disease risk in type 2 diabetes differs between men and women—and sex hormones may be part of the story. In a large Johns Hopkins study, men with higher ...
Feb. 4, 2026 Sound machines may not be the sleep saviors many believe. Researchers found that pink noise significantly reduced REM sleep, while simple earplugs did a better job protecting deep, restorative sleep ...
Feb. 4, 2026 As we age, our cells don’t just wear down—they reorganize. Researchers found that cells actively remodel a key structure called the endoplasmic reticulum, reducing protein-producing regions while ...