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Hair
Hair is a filamentous outgrowth of the skin found only in mammals. The speed of hair growth is roughly 11 cm/yr. The average human head has about 100,000 hair follicles. Older people tend to develop grey hair because the pigment in the hair is lost and the hair becomes colourless. Grey hair is considered to be a characteristic of normal aging. The age at which this occurs varies from person to person, but in general nearly everyone 75 years or older has grey hair, and in general men tend to become grey at younger ages than women.
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Health & Medicine News
September 22, 2026
Sep. 22, 2026 Caffeine may make sleep less restorative even when you fall asleep normally and stay in bed for eight hours, with EEG recordings revealing fewer of the slow brain waves associated with deep sleep. Individual sensitivity varies dramatically, meaning ...
Sep. 22, 2026 A minimally invasive procedure called genicular artery embolization could offer a new middle ground between conservative treatments and knee replacement for osteoarthritis. By blocking tiny blood vessels associated with inflammation, GAE can ...
Sep. 21, 2026 Researchers have found evidence that long COVID may damage dopamine releasing neurons in the brain, potentially explaining persistent fatigue, low motivation, slowed movement, and memory difficulties. The discovery could lead to new treatments that ...
Sep. 21, 2026 Stem cell transplants helped regenerate stroke-damaged brain tissue in mice, producing new neurons and restoring lost motor function. The treatment also improved blood vessels, inflammation, and the blood-brain barrier, raising hopes that a similar ...
Sep. 21, 2026 A large study suggests the cardiovascular benefits of GLP-1 drugs such as Ozempic, Wegovy, Mounjaro, and Zepbound can disappear surprisingly quickly when treatment stops. After two years off the medications, patients had a 22% higher risk of heart ...
Sep. 21, 2026 A new needle-thin brain implant can record neural activity, deliver drugs, and stimulate multiple brain regions using a single flexible fiber. Successful tests in mice suggest it could give ...
Sep. 21, 2026 Chronic inflammation tied to stress, lifestyle, mental health, and socioeconomic conditions may silently change the heart for years before any symptoms appear. People with the highest inflammation levels faced a 43% greater risk of heart attack and ...
Sep. 21, 2026 Scientists have found that the human brain develops from two distinct cellular systems, suggesting that evolution fused together two ancient nervous systems with very different jobs. The discovery ...
Sep. 20, 2026 A sweeping review of more than 153,000 adults found that calcium and vitamin D supplements, alone or together, do little to prevent fractures or falls in most older people. Researchers say the ...
Sep. 20, 2026 Common preservatives hiding in processed foods may carry unexpected heart risks, with heavy consumption linked to substantially higher rates of high blood pressure and cardiovascular disease. Researchers identified eight widely used preservatives ...
Sep. 19, 2026 Researchers have uncovered a hidden molecular warning sign of inflammatory bowel disease (IBD) that can linger even when patients feel well and appear to be in remission. By studying around 900 human gut biopsies and patient-derived mini-intestines, ...
Sep. 19, 2026 A growing Bundibugyo virus outbreak is showing how a little-known relative of Ebola can become a major threat when diagnosis and treatment options are limited. Experts warn that preparing only for familiar pathogens could leave the world vulnerable ...
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Sep. 20, 2026 Ancient DNA reveals that plague repeatedly returned to Europe for more than 400 years after the Black Death, evolving into new lineages and spreading ...
Sep. 19, 2026 Scientists have identified the genetic cause behind the mysterious AnWj blood group antigen, solving a puzzle that began in 1972 and establishing a new blood group system called MAL. The discovery ...
Sep. 18, 2026 Scientists discovered a population of cells that can start the process of programmed cell death, survive it, and then help rapidly rebuild damaged tissue. Their descendants become far more resistant ...
Sep. 18, 2026 Newer blood thinners may do more than prevent strokes in people with Alzheimer’s disease and atrial fibrillation. Researchers found that patients ...
Sep. 17, 2026 Ozempic and other GLP-1 medications can improve blood sugar, weight, and cardiovascular health, but researchers found little evidence that they also improve mental health, employment, marriage, or ...
Sep. 17, 2026 A kimchi-derived bacterium can bind to nanoplastics under gut-like conditions and may help carry them out of the body. In mice, the probiotic more than doubled the amount of nanoplastics detected in ...
Sep. 17, 2026 A natural compound produced by gut bacteria after digesting foods such as pomegranates, walnuts, and berries may help repair and protect the intestinal lining. The discovery reveals a surprising ...
Sep. 17, 2026 Scientists discovered that brain-cell axons may not be smooth tubes as textbooks have shown for more than a century, but instead naturally resemble strings of tiny pearls. Those pearl-like structures ...
Sep. 17, 2026 Scientists are testing a counterintuitive way to fight mesothelioma, an aggressive asbestos-linked cancer with few effective treatments. A new experimental mesothelioma drug kills cancer cells by ...
Sep. 16, 2026 Scientists found that black and green Japanese rice contain unusual, potentially beneficial fats and may be digested more slowly than ordinary white rice. The combination could make these colorful ...