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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
October 6, 2025
Oct. 6, 2025 — A chance encounter with plastic waste on a tropical beach sparked a deep investigation into what those fragments mean for human health. The research reveals that bottled water isn’t as pure as it seems—each sip may contain invisible ...
Oct. 6, 2025 — A University of New Mexico scientist is revealing what might be one of the most overlooked causes of dementia — damage in the brain’s tiny blood vessels. Dr. Elaine Bearer has created a new way to classify these changes, showing that many people ...
Oct. 6, 2025 — Scientists studying tiny roundworms have uncovered how the secrets of a long life can be passed from parents to their offspring — without changing DNA. The discovery shows that when certain cellular structures called lysosomes change in ways that ...
Oct. 5, 2025 — Over 40% of fatal crash victims had THC levels far above legal limits, showing cannabis use before driving remains widespread. The rate didn’t drop after legalization, suggesting policy changes haven’t altered risky habits. Experts warn that the ...
Oct. 5, 2025 — A new study shows glioblastoma isn’t confined to the brain—it erodes the skull and hijacks the immune system within skull marrow. The cancer opens channels that let inflammatory cells enter the brain, fueling its deadly progression. Even drugs ...
Oct. 5, 2025 — Stanford scientists found that aging disrupts the brain’s internal navigation system in mice, mirroring spatial memory decline in humans. Older mice struggled to recall familiar locations, while a few “super-agers” retained youthful brain ...
Oct. 5, 2025 — Researchers from Leeds found that overeating is driven more by what people believe about food than by its actual ingredients or level of processing. Foods perceived as fatty, sweet, or highly processed were more likely to trigger indulgence. ...
Oct. 5, 2025 — Scientists discovered that lifelong social support can slow biological aging. Using DNA-based “epigenetic clocks,” they found that people with richer, more sustained relationships showed younger biological profiles and lower inflammation. The ...
Oct. 5, 2025 — When cancer cells are physically squeezed, they mount an instant, high-energy defense by rushing mitochondria to the cell nucleus, unleashing a surge of ATP that fuels DNA repair and survival. This newly discovered mechanism, visualized in real time ...
Oct. 5, 2025 — Researchers have uncovered how a protein called MRAP2 acts as a key regulator of hunger. It helps move the appetite receptor MC4R to the cell’s surface, allowing it to send stronger “stop eating” signals. The discovery offers new hope for ...
Oct. 4, 2025 — A massive new study combining observational and genetic data overturns the long-held belief that light drinking protects the brain. Researchers found that dementia risk rises in direct proportion to alcohol consumption, with no safe level ...
Oct. 4, 2025 — The STEP UP trials revealed that a 7.2 mg dose of semaglutide led to greater weight loss than the currently approved 2.4 mg dose. Nearly half of participants lost 20% or more of their body weight, ...
Latest Headlines
updated 12:56 pm ET
Oct. 6, 2025 — In a remarkable blend of science and tradition, researchers have revived an old Balkan and Turkish yogurt-making technique that uses ants as natural fermenters. The ants’ bacteria, acids, and ...
Oct. 4, 2025 — Researchers uncovered a key cellular regulator, PP2A-B55alpha, that controls both the cleanup of damaged mitochondria and the creation of new ones. In Parkinson’s disease models, reducing this ...
Oct. 4, 2025 — Scientists discovered that vitamin D2 supplements can lower levels of vitamin D3, the form the body uses most effectively. Unlike D2, vitamin D3 enhances the immune system’s first line of defense ...
Oct. 4, 2025 — A Weill Cornell Medicine team has found that triple-negative breast cancer depends on the enzyme EZH2 to spread. By silencing key genes, EZH2 drives chaotic cell divisions and fuels metastasis. ...
Oct. 4, 2025 — Metabolic dysfunction-associated steatotic liver disease (MASLD) affects over a third of the global population and is linked to serious health problems. A new study has revealed that high blood ...
Oct. 4, 2025 — A Scandinavian clinical trial has revealed that low-dose aspirin can halve the risk of colon and rectal cancer recurrence in patients with specific genetic mutations. The research, involving over ...
Oct. 3, 2025 — New research from Houston Methodist reveals how obesity may directly drive Alzheimer’s disease. Scientists discovered that tiny messengers released by fat tissue, called extracellular vesicles, can ...
Oct. 3, 2025 — A massive nationwide study has linked long-term exposure to the industrial chemical trichloroethylene (TCE) with a higher risk of Parkinson’s disease in older adults. Researchers examined over 1.1 ...
Oct. 3, 2025 — Ohio State researchers have discovered that exhausted T cells collapse under the weight of misfolded proteins, activating a destructive stress response called TexPSR. Unlike normal stress systems, ...
Oct. 3, 2025 — Flu detection could soon be as simple as chewing gum. Scientists have created a molecular sensor that releases a thyme-like flavor when it encounters influenza, offering a low-tech, taste-based ...