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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 1, 2025
Aug. 31, 2025 — A breakthrough pill, baxdrostat, has shown remarkable success in lowering dangerously high blood pressure in patients resistant to standard treatments. In a large international trial, it cut systolic ...
Aug. 31, 2025 — Beta blockers, used for decades after heart attacks, provide no benefit for patients with preserved heart function, according to the REBOOT trial. The massive study also found women faced higher risks when taking the drug. Experts say the results ...
Aug. 31, 2025 — New research suggests that exercise may not just make us feel younger—it could actually slow or even reverse the body’s molecular clock. By looking at DNA markers of aging, scientists found that structured exercise like aerobic and strength ...
Aug. 31, 2025 — Drinking nitrate-rich beetroot juice lowered blood pressure in older adults by reshaping their oral microbiome, according to researchers at the University of Exeter. The study found that beneficial ...
Aug. 30, 2025 — Scientists at Mount Sinai have created an artificial intelligence system that can predict how likely rare genetic mutations are to actually cause disease. By combining machine learning with millions of electronic health records and routine lab tests ...
Aug. 30, 2025 — Scientists have uncovered a surprising new healing mechanism in injured cells called cathartocytosis, in which cells "vomit" out their internal machinery to revert more quickly to a stem cell-like ...
Aug. 30, 2025 — Men eating ultra-processed foods gained more fat than those eating unprocessed meals, even with equal calories. Their hormone levels shifted in worrying ways, with testosterone falling and pollutants rising. Researchers say the processing itself, ...
Aug. 30, 2025 — Scientists have finally uncovered direct genetic evidence of Yersinia pestis — the bacterium behind the Plague of Justinian — in a mass grave in Jerash, Jordan. This long-sought discovery resolves a centuries-old debate, confirming that the ...
Aug. 29, 2025 — Yale scientists discovered that cavefish species independently evolved blindness and depigmentation as they adapted to dark cave environments, with some lineages dating back over 11 million years. This new genetic method not only reveals ancient ...
Aug. 29, 2025 — Quantum scientists in Innsbruck have taken a major leap toward building the internet of the future. Using a string of calcium ions and finely tuned lasers, they created quantum nodes capable of generating streams of entangled photons with 92% ...
Aug. 29, 2025 — A Mediterranean diet alone is healthy, but when combined with calorie control, exercise, and support, it cuts type 2 diabetes risk by 31%. The PREDIMED-Plus study followed almost 5,000 participants for six years, making it Europe’s largest ...
Aug. 29, 2025 — For people with macular telangiectasia type 2 (MacTel), an orphan retinal disorder that gradually destroys central vision, there have long been no approved treatment options. But now, a new study sponsored by Neurotech Pharmaceuticals and ...
Latest Headlines
updated 12:56 pm ET
Aug. 29, 2025 — Harvard scientists have uncovered that lithium, a naturally occurring element in the brain, may be the missing piece in understanding Alzheimer’s. Their decade-long research shows that lithium ...
Aug. 28, 2025 — Using cannabis to self-medicate comes with hidden dangers—new research shows these users face higher paranoia and consume more THC. Childhood trauma further amplifies the risks, especially ...
Aug. 28, 2025 — A Mediterranean-style diet was linked to lower dementia risk, especially in people with high-risk Alzheimer’s genes. The strongest benefits were seen in those with two APOE4 copies, showing diet ...
Aug. 27, 2025 — Researchers propose that the U.S. could safely drop adult tetanus and diphtheria boosters, saving $1 billion annually, since childhood vaccinations ...
Aug. 26, 2025 — Scientists at Kyoto University have uncovered a hidden protein complex that organizes DNA in sperm stem cells, a discovery that reveals surprising ties between fertility and cancer. When this ...
Aug. 26, 2025 — University of Minnesota researchers developed a 3D-printed scaffold that directs stem cells to grow into functioning nerve cells, successfully restoring movement in rats with severed spinal cords. ...
Aug. 26, 2025 — Scientists have cracked one of chemistry’s toughest challenges with indoles, using copper to unlock a spot once thought too stubborn to change. The ...
Aug. 26, 2025 — Knee osteoarthritis is a major cause of pain and disability, but routine X-rays often do more harm than good. New research shows that being shown an X-ray can increase anxiety, make people fear ...
Aug. 26, 2025 — A nationwide study found that recent colds caused by rhinoviruses can give short-term protection against COVID-19. Children benefit most, as their immune systems react strongly with antiviral ...
Aug. 26, 2025 — Australian teachers are in crisis, with 9 in 10 experiencing severe stress and nearly 70% saying their workload is unmanageable. A major UNSW Sydney study found teachers suffer depression, anxiety, ...