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Estrogen
Estrogens (also oestrogens) are a group of steroid compounds, named for their importance in the oestrus cycle, and functioning as the primary female sex hormone. While estrogens are present in both men and women, they are usually present at significantly higher levels in women of reproductive age. They promote the development of female secondary sex characteristics, such as breasts, and are also involved in the thickening of the endometrium and other aspects of regulating the menstrual cycle. Like all steroid hormones, estrogens readily diffuse across the cell membrane; inside the cell, they interact with estrogen receptors. The three major naturally occurring estrogens in women are estradiol, estriol and estrone. Estrogens are used as part of some oral contraceptives and also in estrogen replacement therapy of post-menopausal women.
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Health & Medicine News
February 5, 2026
Feb. 5, 2026 Researchers have figured out how psoriasis can quietly turn into joint disease for some patients. Immune cells formed in inflamed skin can travel through the blood and reach the joints, where they sometimes trigger inflammation. The key difference ...
Feb. 5, 2026 People who switch to a fully unprocessed diet don’t just eat differently—they eat smarter. Research from the University of Bristol shows that when people avoid ultra-processed foods, they naturally pile their plates with fruits and vegetables, ...
Feb. 5, 2026 Kidney disease often creeps in silently, and many patients aren’t diagnosed until major damage is already done. New research shows that even “normal” kidney test results can signal danger if they’re unusually low for someone’s age. By ...
Feb. 5, 2026 Researchers have created the first complete map showing how hundreds of mutations in a key cancer gene affect tumor growth. By testing every possible mutation in a critical hotspot, they found that some changes barely boost cancer signals, while ...
Feb. 5, 2026 Advanced care provided by air ambulance teams was linked to higher survival rates in major trauma patients. Researchers found that more people survived than predicted by standard models, including many with severe injuries and low chances of ...
Feb. 5, 2026 As bird flu continues to circulate in animals and spill over into humans, researchers are racing to stop it before it adapts to spread widely between people. A new nasal spray vaccine showed strong protection against H5N1 in animal tests, ...
Feb. 4, 2026 Popular weight-loss drugs like Ozempic and Wegovy can dramatically curb appetite, but experts warn many users are flying blind when it comes to nutrition. New research suggests people taking these medications may not be getting enough guidance on ...
Feb. 4, 2026 A massive Swedish study tracking nearly 28,000 people for 25 years found an unexpected link between full-fat dairy and brain health. Among adults without a genetic risk for Alzheimer’s, eating more full-fat cheese was associated with a noticeably ...
Feb. 4, 2026 Scientists are digging into why heart disease risk in type 2 diabetes differs between men and women—and sex hormones may be part of the story. In a large Johns Hopkins study, men with higher testosterone had lower heart disease risk, while rising ...
Feb. 4, 2026 Sound machines may not be the sleep saviors many believe. Researchers found that pink noise significantly reduced REM sleep, while simple earplugs did a better job protecting deep, restorative sleep from traffic noise. When pink noise was combined ...
Feb. 4, 2026 As we age, our cells don’t just wear down—they reorganize. Researchers found that cells actively remodel a key structure called the endoplasmic reticulum, reducing protein-producing regions while preserving fat-related ones. This process, driven ...
Feb. 3, 2026 Plants make chemical weapons to protect themselves, and many of these compounds have become vital to human medicine. Researchers found that one powerful plant chemical is produced using a gene that looks surprisingly bacterial. This suggests plants ...
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Feb. 2, 2026 Chronic stress can damage the gut’s protective lining, triggering inflammation that may worsen depression. New research shows that stress lowers levels of a protein called Reelin, which plays a key ...
Feb. 2, 2026 MMS has long been promoted as a miracle cure, but new research shows it’s essentially a toxic disinfectant. While it can kill bacteria, it only works at levels that also damage human cells and ...
Feb. 1, 2026 Researchers studying nearly 2 million older adults found that cerebral amyloid angiopathy sharply raises the risk of developing dementia. Within five years, people with the condition were far more ...
Feb. 1, 2026 When the brain rests, it usually replays recent experiences to strengthen memory. Scientists found that in Alzheimer’s-like mice, this replay still occurs — but the signals are jumbled and poorly ...
Feb. 1, 2026 Middle age is becoming a tougher chapter for many Americans, especially those born in the 1960s and early 1970s. Compared with earlier generations, they report more loneliness and depression, along ...
Feb. 1, 2026 Researchers found that small doses of an antibiotic can coax gut bacteria into producing a life-extending compound. In worms, this led to longer lifespans, while mice showed healthier cholesterol and ...
Feb. 1, 2026 Researchers in Bangladesh have identified a bat-borne virus, Pteropine orthoreovirus, in patients who were initially suspected of having Nipah virus but tested negative. All had recently consumed raw ...
Jan. 31, 2026 Statins are a cornerstone of heart health, but muscle pain and weakness cause many patients to quit taking them. Scientists have now identified the precise molecular trigger behind these side ...
Jan. 31, 2026 Lowering salt in everyday foods could quietly save lives. Researchers found that modest sodium reductions in bread, packaged foods, and takeout meals could significantly reduce heart disease and ...
Jan. 30, 2026 People who naturally stay up late may be putting their hearts under added strain as they age. A large study tracking more than 300,000 adults found that middle-aged and older night owls had poorer ...