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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
January 21, 2026
Jan. 21, 2026 A major global study suggests that a hidden mismatch between two common blood tests could quietly signal serious trouble ahead. When results from creatinine and cystatin C—two markers used to assess kidney health—don’t line up, the risk of ...
Jan. 21, 2026 Researchers from New England Biolabs (NEB®) and Yale University describe the first fully synthetic bacteriophage engineering system for Pseudomonas aeruginosa, an antibiotic-resistant bacterium of global concern, in a new PNAS study. The system ...
Jan. 21, 2026 A new study suggests that micro-doses of THC could help counter many long-term side effects of HIV treatment without causing intoxication. In animal models, low-dose THC reduced inflammation, improved gut bacteria, boosted serotonin, and lowered ...
Jan. 20, 2026 Scientists at Stanford Medicine have discovered a treatment that can reverse cartilage loss in aging joints and even prevent arthritis after knee injuries. By blocking a protein linked to aging, the therapy restored healthy, shock-absorbing ...
Jan. 20, 2026 Researchers report that vagus nerve stimulation helped many people with long-standing, treatment-resistant depression feel better—and stay better—for at least two years. Most participants had ...
Jan. 20, 2026 Scientists have uncovered why people with chronic kidney disease so often die from heart problems: damaged kidneys release tiny particles into the bloodstream that actively poison the heart. These particles, produced only by diseased kidneys, carry ...
Jan. 20, 2026 Researchers have identified a key molecular interaction that accelerates Parkinson’s disease by damaging the brain’s energy systems. They designed a new treatment that intercepts this harmful ...
Jan. 20, 2026 Ibuprofen may be doing more than easing aches and pains—it could also help reduce the risk of some cancers. Studies have linked regular use to lower rates of endometrial and bowel cancer, likely because the drug dampens inflammation that fuels ...
Jan. 20, 2026 Researchers have found a reliable way to grow helper T cells from stem cells, solving a major challenge in immune-based cancer therapy. Helper T cells act as the immune system’s coordinators, helping other immune cells fight longer and harder. The ...
Jan. 20, 2026 Scientists have uncovered a surprising reason why some chronic wounds refuse to heal, even when treated with antibiotics. A common bacterium found in long-lasting wounds does not just resist drugs. It actively releases damaging molecules that ...
Jan. 20, 2026 Scientists have uncovered new clues about why diabetic foot infections can become so severe and difficult to treat. By analyzing the DNA of E. coli bacteria taken from infected wounds around the world, researchers found an unexpected level of ...
Jan. 19, 2026 A major new scientific review brings reassuring news for expectant parents: using acetaminophen, commonly known as Tylenol, during pregnancy does not increase a child’s risk of autism, ADHD, or intellectual disability. Researchers analyzed 43 ...
Latest Headlines
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Jan. 19, 2026 Scientists at Johns Hopkins have uncovered a surprising new way to influence brain activity by targeting a long-mysterious class of proteins linked to anxiety, schizophrenia, and movement disorders. ...
Jan. 19, 2026 Cannabis-based medicines have been widely promoted as a potential answer for people living with chronic nerve pain—but a major new review finds the evidence just isn’t there yet. After analyzing ...
Jan. 18, 2026 Scientists have discovered that breast cancer can quietly throw the brain’s internal clock off balance—almost immediately after cancer begins. In mice, tumors flattened the natural daily rhythm ...
Jan. 18, 2026 Researchers have identified OTULIN, an immune-regulating enzyme, as a key trigger of tau buildup in the brain. When OTULIN was disabled, tau vanished from neurons and brain cells remained healthy. ...
Jan. 18, 2026 While social media continues to circulate claims linking acetaminophen to autism in children, medical experts say those fears distract from a far more serious and proven danger: overdose. ...
Jan. 18, 2026 When scientists sent bacteria-infecting viruses to the International Space Station, the microbes did not behave the same way they do on Earth. In microgravity, infections still occurred, but both ...
Jan. 18, 2026 A long-running Swedish study has followed adults for nearly five decades, uncovering when physical decline truly begins. Fitness and strength start slipping around age 35, then worsen gradually with ...
Jan. 17, 2026 Scientists are uncovering a hidden and surprisingly complex earthquake zone beneath Northern California by tracking swarms of tiny earthquakes that are far too weak to feel. These faint tremors are ...
Jan. 17, 2026 Thyme extract is packed with health-promoting compounds, but it is difficult to control and easy to waste. Researchers created a new technique that traps tiny amounts of the extract inside ...
Jan. 17, 2026 Researchers have turned artificial intelligence into a powerful new lens for understanding why cancer survival rates differ so dramatically around the world. By analyzing cancer data and health ...