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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
September 12, 2025
Sep. 12, 2025 — Walking every day could be the simplest and most effective way to prevent chronic lower back pain. A large study involving over 11,000 people found that walking more — not faster — reduces the risk of developing long-term back issues. The ...
Sep. 12, 2025 — Forever chemicals known as PFAS have turned up in an unexpected place: beer. Researchers tested 23 different beers from across the U.S. and found that 95% contained PFAS, with the highest concentrations showing up in regions with known water ...
Sep. 11, 2025 — Researchers have discovered that everyday substances like caffeine can influence how bacteria such as E. coli respond to antibiotics. By examining 94 common drugs and food ingredients, scientists found that certain compounds trigger genetic ...
Sep. 11, 2025 — New research suggests that immunotherapy given before and after surgery could help patients with diffuse pleural mesothelioma, one of the most challenging cancers to treat. A phase II clinical trial tested immunotherapy in resectable cases, with ...
Sep. 11, 2025 — Researchers at NYU Langone Health discovered that cutting off blood flow accelerates cancer growth by prematurely aging the bone marrow and weakening the immune system. In mouse models, restricted blood flow doubled the growth rate of breast tumors, ...
Sep. 10, 2025 — Scientists in Canada have uncovered a surprising culprit behind high blood sugar and liver problems: a hidden fuel made by gut bacteria. This little-known molecule, called D-lactate, slips into the ...
Sep. 10, 2025 — Glioblastoma’s stealthy spread has met a new challenge: MRI-powered fluid flow mapping that reveals where the cancer is likely to invade next. The innovation is now being advanced by a spinoff company to guide personalized cancer ...
Sep. 10, 2025 — Scientists at Stellenbosch University have uncovered a rare class of plant compounds, flavoalkaloids, in Cannabis leaves for the first time. Using advanced two-dimensional chromatography and mass spectrometry, they identified 79 phenolic compounds ...
Sep. 10, 2025 — Metformin, long trusted for diabetes, turns out to work in the brain too. By shutting down Rap1 in the hypothalamus, the drug lowers blood sugar more effectively than previously understood, opening doors for new ...
Sep. 9, 2025 — What we eat as we age may determine how many chronic illnesses we face later in life. A 15-year study of more than 2,400 older adults reveals that diets rich in vegetables, whole grains, nuts, and healthy fats slow the accumulation of diseases like ...
Sep. 9, 2025 — Scientists discovered that certain blood proteins linked to brain injury and inflammation strongly correlate with early signs of memory and cognitive decline, especially in Hispanic and Latino adults. This breakthrough points to a future where ...
Sep. 9, 2025 — Thousands of women are using GLP-1 drugs like Ozempic for weight loss without contraception, leading to unintended pregnancies and potential risks for unborn babies. Experts warn clearer medical guidance is urgently ...
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Sep. 9, 2025 — Orangutans, humans’ close evolutionary relatives, have developed remarkable strategies to survive in the unpredictable rainforests of Borneo. A Rutgers-led study reveals that these apes balance ...
Sep. 8, 2025 — Scientists have discovered that even short-term exposure to polluted air can speed up Alzheimer’s, worsening toxic protein buildup in the brain and accelerating memory loss. The research connects ...
Sep. 8, 2025 — UC Berkeley researchers mapped the brain circuits that control growth hormone during sleep, uncovering a feedback system where sleep fuels hormone release, and the hormone regulates wakefulness. The ...
Sep. 8, 2025 — Scientists discovered seven molecules in the blood linked to excessive daytime sleepiness, a condition that affects one in three Americans and raises the risk of heart disease, obesity, and diabetes. ...
Sep. 8, 2025 — Scientists at Leipzig University have identified a little-known receptor, GPR133, as a key player in bone health. By stimulating this receptor with a new compound called AP503, they were able to ...
Sep. 8, 2025 — Researchers have uncovered why older adults are more vulnerable to severe flu. The culprit is a protein called ApoD, which rises with age and ...
Sep. 8, 2025 — Tiny diatoms and their bacterial partners act as nature’s nutrient factories, fueling insects and salmon in California’s Eel River. Their pollution-free process could inspire breakthroughs in ...
Sep. 8, 2025 — Scientists from Finland and the UK have uncovered groundbreaking evidence that heart attacks may be triggered by infectious processes rather than just cholesterol and lifestyle factors. Hidden ...
Sep. 8, 2025 — Researchers studying over 1,000 children found that omega-3 fatty acids may help protect against myopia, while saturated fats may increase risk. Kids with more omega-3 in their diet had healthier eye ...
Sep. 8, 2025 — Scientists have uncovered a surprising new pathway behind life-threatening food allergies. Instead of histamine, a different chemical called leukotrienes drives severe reactions in the gut. These ...