Reference Terms
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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
May 17, 2026
May 17, 2026 Studies suggest watermelon could be a hidden powerhouse for better health. Researchers found that people who eat watermelon tend to have higher-quality diets packed with more vitamins, fiber, and antioxidants — while consuming less added sugar and ...
May 17, 2026 Scientists have discovered that the human body undergoes a dramatic internal transformation during extended fasting, with major changes appearing only after about three days without food. In a seven-day water-only fasting study, researchers tracked ...
May 17, 2026 A new nanotechnology treatment reversed Alzheimer’s symptoms in mice by restoring the brain’s natural cleanup system. The specially engineered nanoparticles helped clear toxic amyloid proteins from the brain and repair the blood-brain barrier, ...
May 17, 2026 For years, “yo-yo dieting” has been blamed for wrecking metabolism and causing lasting damage, but a major new review says the fear may be wildly overblown. After analyzing decades of studies in humans and animals, researchers found little ...
May 17, 2026 Scientists have uncovered a surprising new trick used by one of cancer’s most notorious proteins. MYC, already infamous for fueling runaway tumor growth, also appears to help cancer cells survive by repairing their damaged DNA — including damage ...
May 16, 2026 Exercise may be training your brain just as much as your body. Researchers discovered that certain brain cells stay highly active even after a workout ends, and those lingering signals appear to help the body build endurance over time. In ...
May 16, 2026 Researchers have shown for the first time that malfunctioning mitochondria — the cell’s energy generators — may directly cause cognitive decline in neurodegenerative diseases. By creating a new tool that temporarily boosts mitochondrial ...
May 16, 2026 A major analysis of brain scans found that people with anxiety disorders have noticeably lower levels of choline, a nutrient crucial for healthy brain function. The strongest evidence appeared in the prefrontal cortex, the region tied to emotional ...
May 16, 2026 A new study suggests microscopic particles from the gut may actively drive inflammation and chronic diseases associated with aging. Remarkably, gut particles from young animals appeared to counter ...
May 15, 2026 Scientists are uncovering a surprising link between hidden tooth infections and blood sugar problems. Deep infections around tooth roots can create chronic inflammation that spreads through the body and may interfere with insulin function. Studies ...
May 15, 2026 You may not need hours at the gym to boost your health after all. Researchers say just 30 minutes of high-intensity exercise per week — broken into tiny bursts of effort that leave you out of ...
May 15, 2026 Cannabis use among older adults is rising fast, but today’s marijuana is far more potent than many people realize — and experts warn the risks may be underestimated. Stanford Medicine specialists ...
Latest Headlines
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May 15, 2026 Scientists have uncovered a surprising dark side to vitamin B2: it may help cancer cells stay alive. The vitamin supports a cellular shield that protects tumors from ferroptosis, a form of programmed ...
May 15, 2026 Scientists have uncovered evidence that serotonin — the same brain chemical boosted by many antidepressants — may actually worsen tinnitus. Using advanced light-based brain stimulation in mice, ...
May 15, 2026 Researchers analyzing over 20,000 patients found that very high levels of the inherited cholesterol particle Lp(a) dramatically raise the risk of ...
May 15, 2026 A casual conversation between graduate students helped spark a breakthrough in aging research at Mayo Clinic. Researchers discovered that tiny synthetic DNA molecules called aptamers can selectively ...
May 15, 2026 A groundbreaking Swedish study that tracked people for nearly 50 years has revealed when the body’s physical decline quietly begins. Researchers found that fitness, strength, and muscle endurance ...
May 14, 2026 Colorectal cancer is increasingly showing up in younger adults, with cases now appearing in people as young as their thirties — often with no family history or warning signs. A major Swiss study ...
May 14, 2026 A daily multivitamin may help slow biological aging, according to researchers studying older adults in a large clinical trial. After two years, participants taking multivitamins showed slower aging ...
May 14, 2026 Scientists analyzing the genomes of thousands of people across Japan discovered evidence for a previously overlooked third ancestral group, challenging the long-accepted “dual origins” theory. ...
May 13, 2026 UC Davis researchers created brand-new psychedelic-like compounds by shining UV light on amino acid-based molecules. These compounds activated key serotonin receptors tied to brain plasticity and ...
May 13, 2026 A huge long-term study found that drinking two to three cups of coffee a day was linked to a much lower risk of dementia, especially before age 75. Researchers say caffeine may help keep brain cells ...