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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
November 4, 2025
Nov. 4, 2025 — A new compound called CMX410 may change the fight against tuberculosis. It targets a weak point in the bacteria’s defenses, even in drug-resistant forms of the disease. Created using a cutting-edge chemistry method, the drug shows promise for ...
Nov. 4, 2025 — Walking a few thousand steps daily may help hold off Alzheimer’s for years, a Mass General Brigham study found. Even moderate physical activity slowed both cognitive decline and the buildup of harmful tau proteins in the brain. The researchers say ...
Nov. 4, 2025 — A collaboration between Brazilian and German researchers has led to a sunflower-based meat substitute that’s high in protein and minerals. The new ingredient, made from refined sunflower flour, delivers excellent nutritional value and a mild ...
Nov. 4, 2025 — Researchers have discovered a specific set of neurons in the amygdala that can trigger anxiety and social deficits when overactive. By restoring the excitability balance in this brain region, they successfully reversed these symptoms in mice. The ...
Nov. 4, 2025 — Using powerful 7-Tesla brain imaging, researchers mapped how the brainstem manages pain differently across the body. They discovered that distinct regions activate for facial versus limb pain, showing the brain’s built-in precision pain control ...
Nov. 4, 2025 — Long-term melatonin use for sleep problems may come with unexpected heart dangers. Researchers found that chronic users were almost twice as likely to die and 3.5 times more likely to be hospitalized for heart failure. Though melatonin is widely ...
Nov. 3, 2025 — UC San Diego researchers combined artificial intelligence with molecular biology to unravel how immune cells in the gut decide between inflammation and healing, a process gone awry in Crohn’s disease. They discovered that the NOD2 gene’s ...
Nov. 3, 2025 — Boston researchers linked nighttime light exposure to greater stress-related brain activity and inflamed arteries, signaling a higher risk of heart disease. The study suggests that artificial light at night disrupts normal stress responses, leading ...
Nov. 3, 2025 — Duke-NUS scientists unveiled BrainSTEM, a revolutionary single-cell map that captures the full cellular diversity of the developing human brain. The project’s focus on dopamine neurons provides crucial insight for Parkinson’s treatment. Their ...
Nov. 3, 2025 — Scientists uncovered how the amino acid leucine enhances mitochondrial efficiency by preserving crucial proteins that drive energy production. By downregulating the protein SEL1L, leucine prevents unnecessary degradation and strengthens the cell’s ...
Nov. 3, 2025 — Penn State scientists uncovered an ancient bacterial defense where dormant viral DNA helps bacteria fight new viral threats. The enzyme PinQ flips bacterial genes to create protective proteins that block infection. Understanding this mechanism could ...
Nov. 3, 2025 — A team of scientists has developed a highly accurate blood test for Chronic Fatigue Syndrome. The test reads tiny DNA patterns that reveal the biological signature of the illness. For millions who’ve faced doubt and misdiagnosis, it’s a ...
Latest Headlines
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Nov. 3, 2025 — Disrupted sleep patterns in Alzheimer’s disease may be more than a symptom—they could be a driving force. Researchers at Washington University found that the brain’s circadian rhythms are ...
Nov. 3, 2025 — Scientists have discovered that a “longevity gene” found in people who live beyond 100 can reverse heart aging in models of Progeria, a devastating disease that causes children to age rapidly. By ...
Nov. 2, 2025 — Cognitive struggles are climbing across the U.S., especially among young and economically disadvantaged adults. Rates of self-reported cognitive disability nearly doubled in people under 40 between ...
Nov. 1, 2025 — Researchers discovered that altering the body’s natural rhythm can help protect the brain from Alzheimer’s damage. By turning off a circadian protein in mice, they raised NAD+ levels and reduced ...
Nov. 1, 2025 — New research from Australia overturns the old idea that exercise “uses up” heartbeats. It shows that fitter people actually use fewer total heartbeats each day thanks to their lower resting heart ...
Nov. 1, 2025 — More screen time among children and teens is linked to higher risks of heart and metabolic problems, particularly when combined with insufficient sleep. Danish researchers discovered a measurable ...
Oct. 31, 2025 — People living in socially and economically disadvantaged neighborhoods may face higher dementia risks, according to new research from Wake Forest University. Scientists found biological signs of ...
Oct. 31, 2025 — Scientists discovered that a blood molecule called CtBP2 may play a major role in how we age. It helps regulate metabolism and appears to link aging across the entire body. Lower levels are tied to ...
Oct. 31, 2025 — Semaglutide appears to safeguard the heart even when patients lose little weight. In a massive international trial, heart attack and stroke risk dropped by 20% regardless of BMI. The benefit seems ...
Oct. 30, 2025 — Researchers in Japan have revealed how some gourds draw pollutants into their fruits. The secret lies in a protein that carries contaminants through the plant sap. By manipulating this protein’s ...