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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

May 22, 2026

Scientists have identified potentially cancer-causing chemicals hiding in many everyday foods, especially those exposed to high heat cooking methods like grilling, roasting, smoking, and frying. The compounds, known as PAHs, can form during cooking ...
A new clinical trial suggests that eating beef every day may not be as risky for people with prediabetes as many assume. Researchers found that adults who ate 6–7 ounces of beef daily for a month showed no worsening in blood sugar control, insulin ...
Getting enough vitamin B12 to meet current health guidelines may not actually be enough to protect the aging brain. Researchers at UC San Francisco found that older adults with “normal” but lower ...
A surprisingly simple walking tweak may offer new hope for millions living with knee osteoarthritis. In a year-long clinical trial, researchers found that slightly changing the angle of a person’s ...
Researchers have discovered that the GLP-1 hormone targeted by drugs like Wegovy is present in very low amounts inside the joints of arthritis patients. That finding suggests high-dose GLP-1 ...
Scientists are uncovering a surprising truth about aging cells: some may damage the body, while others help protect it. The discovery is fueling a new wave of precision anti-aging therapies aimed at ...
A new theory suggests many age-related diseases may actually start decades before symptoms appear. Researchers say early-life damage — from infections, injuries, or genetic mutations — can remain ...
Eating too much junk food early in life may rewire the brain in ways that last into adulthood, even after switching to a healthier diet. Scientists found that high-fat, high-sugar diets changed feeding behavior and disrupted appetite-control regions ...
A huge international review found that GLP-1 weight-loss drugs significantly reduce the risk of heart attacks, strokes, heart failure, and premature death over the long term. Researchers say these ...
Scientists have uncovered alarming new evidence that a common insecticide may leave lasting marks on the developing brain before a child is even born. Researchers studying New York City children found that prenatal exposure to chlorpyrifos — a ...
Scientists have unveiled a powerful new tool called PerturbFate that could change how researchers tackle diseases driven by huge numbers of genetic mutations, including cancer and Alzheimer’s. Instead of trying to target every faulty gene ...
Researchers discovered that leucine, a nutrient found in protein-rich foods, can supercharge mitochondria by protecting crucial energy-producing proteins inside cells. The breakthrough uncovers a powerful new link between diet and cellular energy ...

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