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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 24, 2026
Aug. 24, 2026 Common medications may reshape the gut microbiome long after the last dose is taken. In a study of more than 2,500 people, researchers found lasting microbial changes linked not only to antibiotics, but also to antidepressants, beta-blockers, ...
Aug. 24, 2026 Backyard bird feeders could become unexpected hotspots for H5N1 as Australia’s bird flu outbreak spreads, bringing species together in ways that rarely occur naturally. Experts say stopping feeding is safest, while smaller amounts of food, no ...
Aug. 24, 2026 Both too little and too much sleep may be linked to faster aging throughout the body. Researchers analyzing 23 biological aging clocks found the lowest aging levels among people sleeping about 6.4 to 7.8 hours per day. Short or long sleep was also ...
Aug. 23, 2026 Gut bacteria can transform nitrate and plant-based iron from vegetables and other foods into protective molecules that may benefit the heart and metabolism. In experimental models, higher levels of these compounds were linked to lower blood ...
Aug. 23, 2026 Researchers have uncovered a possible reason why the Alzheimer’s risk gene APOE4 can disrupt the brain long before memory problems begin. In mice, APOE4 increased a protein called Nell2, shrinking ...
Aug. 23, 2026 Researchers have found a way to slash the processing time for 3D-printed zirconia crowns from as much as 100 hours to under 30 minutes. The advance could eventually let dentists print strong, customized permanent crowns for patients within a single ...
Aug. 23, 2026 Researchers have used AI to uncover the DNA signature of a key genetic “switch” involved in turning genes on. After analyzing about 500,000 DNA sequences, the model identified the initiator in roughly 60% of human genes. The breakthrough could ...
Aug. 23, 2026 A decades-old compound may point to a new way of treating obesity by making the body burn more energy rather than simply reducing appetite. In mice, TOFA increased energy use by as much as 18%, reduced body fat without significant muscle loss, and ...
Aug. 23, 2026 A massive analysis involving more than 100 million people has found strong links between recreational drug use and stroke, including among younger adults. Cocaine was associated with nearly double the risk of stroke, amphetamines with more than ...
Aug. 23, 2026 Older adults with mild cognitive impairment and sleep problems who took at least 5,000 IU of vitamin D daily scored more than 13% higher on a cognitive test than those taking none. The preliminary findings suggest vitamin D could be worth studying ...
Aug. 22, 2026 Mice that developed compulsive drinking after alcohol abstinence showed more than double the activity in a brain region associated with stress and addiction. Because the signal appeared before they drank again, researchers think it could eventually ...
Aug. 22, 2026 Peppermint oil may have an unexpected benefit for people with mildly high blood pressure. Adults who took a small dose twice daily for 20 days saw their systolic blood pressure fall by an average of 8.5 mmHg, while a placebo group showed little ...
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updated 12:56 pm ET
Aug. 22, 2026 Greenland sharks may live for 400 years without suffering the kind of retinal decline normally associated with aging. Researchers found healthy eye tissue and active proteins specially adapted for ...
Aug. 22, 2026 Exercise may not be a powerful weight-loss tool on its own, but it appears to play a much bigger role in preventing lost weight from returning. By preserving muscle, supporting metabolism, improving ...
Aug. 22, 2026 People who speak several languages may have brains that age more slowly, with four-language speakers showing brains that appeared about 13 years younger than those of monolinguals. Starting earlier ...
Aug. 22, 2026 A simple yeast-based food supplement may help restore the immune system’s ability to fight cancer, according to new research in mice. Scientists found that yeast beta-glucan reprogrammed early ...
Aug. 21, 2026 Pancreatic cancer patients with at least 21 natural teeth survived nearly two years longer after surgery than those with fewer teeth in a study of 339 people. Researchers suspect tooth loss may ...
Aug. 21, 2026 Scientists have linked a specific gut bacterium, Roseburia inulinivorans, to stronger muscles in both humans and mice. Older adults who carried it had 29% greater handgrip strength, while treated ...
Aug. 21, 2026 A few minutes of sprinting may reshape the bloodstream far more dramatically than a much longer moderate workout. Six 30-second sprints altered nearly a quarter of the blood proteins measured and ...
Aug. 21, 2026 A hormone already known for curbing appetite and supporting weight loss may have a surprising second job: protecting the liver from inflammation and scarring. Researchers at McMaster University found ...
Aug. 21, 2026 AI may be able to predict how strongly someone will respond to a vaccine before they receive it. By analyzing antibody patterns in more than 4,000 people, researchers found signs of “immune ...
Aug. 21, 2026 People who participated in colorectal cancer screening had a 43% lower risk of dying from the disease, according to long-term data from more than 376,000 people in Sweden. The findings suggest that ...