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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
August 7, 2026
Aug. 7, 2026 Linus Pauling was widely mocked for claiming that vitamin C could fight cancer, especially after trials using vitamin C pills showed no benefit. Researchers now know that intravenous vitamin C reaches vastly higher concentrations and can behave more ...
Aug. 7, 2026 Blocking the glycine transporter SLC6A20 restored important brain signaling and improved social, communication, and repetitive behaviors in autism-related mouse models. The treatment also worked in human brain organoids and showed lasting effects in ...
Aug. 7, 2026 A ten-month Antarctic experiment found that astronauts may struggle not only with loneliness but also with spending too much time around the same people. Frequent contact was linked to greater ...
Aug. 7, 2026 A new wearable patch may help people reach REM sleep faster and remain there longer without medication or surgery. In a study of 28 participants, the device shortened the time to REM by 43 minutes and extended it by about 16 minutes. Researchers ...
Aug. 6, 2026 Beginning around age 50, the brain’s memory center appears to lose many of its longtime immune cells and replace them with more inflammatory ones. This surprising shift may help explain how normal aging sets the stage for Alzheimer’s disease and ...
Aug. 6, 2026 A long-term brain study found that common risks such as smoking, high blood pressure, heart disease, and high blood lipids were strongly linked to damage associated with vascular dementia. The findings suggest that healthier lifestyle choices could ...
Aug. 6, 2026 Genetic changes may set off a chain reaction that causes the spine’s natural shock absorbers to harden and deteriorate. Zebrafish with a faulty collagen-related gene developed mineral buildup and spinal fusion similar to human disc disease. ...
Aug. 5, 2026 Tiny pollution particles from smoke, soot, and dust may worsen rheumatoid arthritis and raise the risk of painful flares, particularly after prolonged exposure. The findings suggest that avoiding poor air quality could become an important part of ...
Aug. 5, 2026 A prescription form of THC helped many people with PTSD escape recurring trauma-related nightmares, with more than one-third reporting that the nightmares disappeared completely after ten weeks. The ...
Aug. 5, 2026 A simple change in posture may subtly affect how people feel and make decisions. Participants who sat upright reported greater feelings of pride and took more successful risks in a virtual balloon game than those who hunched over. Most did not ...
Aug. 5, 2026 Stanford researchers discovered immune cells in flatworms that explode within minutes, killing nearby bacteria and foreign cells before vanishing completely. Their unusually fast and localized attack ...
Aug. 4, 2026 A specially engineered chewing gum reduced HPV by up to 93% and nearly eliminated two bacteria linked to head and neck cancer. The treatment preserved beneficial mouth bacteria, raising hopes for a safer and more affordable ...
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Aug. 4, 2026 Chemotherapy-surviving ovarian cancer cells may release fructose to help neighboring tumor cells loosen, escape, and spread. The discovery suggests that sugary diets and cholesterol-lowering drugs ...
Aug. 3, 2026 Weight loss is not simply a test of willpower. The human brain evolved to protect body fat during times of scarcity, and it can treat a previously higher weight as the new normal, triggering stronger ...
Aug. 3, 2026 Low arginine levels may allow cancer cells and viruses to slip past the immune system by reducing production of a crucial cellular warning protein. In mice, arginine-rich diets led to fewer colon ...
Aug. 3, 2026 Scientists have identified a molecular switch that may help explain why aging makes the brain more vulnerable to diseases such as ALS and Huntington’s. In worms, the protein EPS8 builds up with age ...
Aug. 3, 2026 Vanderbilt researchers created the first selective compound designed to inhibit TAOK-1, a poorly understood protein connected to Alzheimer’s disease. They also discovered a second compound that ...
Aug. 3, 2026 Scientists have figured out how two famously poisonous plants create chemicals with surprising medical potential. After tracking thousands of genes in wolfsbane and larkspur, they identified six ...
Aug. 2, 2026 A protein once thought to mainly protect chromosome ends may also be essential for keeping muscle stem cells ready to repair injuries. Researchers found that TRF2 helps these cells maintain their ...
Aug. 2, 2026 A surprisingly small dose of exercise may deliver major health benefits for adults carrying excess fat around the waist. In a four-month trial involving 315 adults with central obesity, researchers ...
Aug. 2, 2026 A sweeping review of more than 350 studies suggests that the protein boom may be overselling what many people actually need. Eating less protein appears to improve metabolism, reduce inflammation and ...
Aug. 2, 2026 Cancer cells rely on powerful genetic switches to keep growth genes running at full speed, but that intense activity can damage their own DNA. The resulting breaks are repeatedly repaired, sometimes ...