Health News

A new analysis suggests mammograms may lead to far less breast cancer overdiagnosis than some earlier studies indicated. Researchers reexamined all eight major randomized screening trials and accounted for differences in follow-up time, screening frequency, and screening after trials ended. Their results were consistent with an overdiagnosis rate below 5%, rather than estimates approaching 30% to 50%.

Researchers found that scented cleaners can react with ozone indoors to create billions or trillions of invisible nanoparticles that can penetrate deep into the lungs. The pollution forms within minutes and, in some cases, may produce an inhaled particle dose comparable to or greater than standing near heavy traffic.

Tirzepatide, sold as Mounjaro and Zepbound, activated calorie-burning brown fat in obese mice, revealing a potential metabolic effect beyond appetite suppression. If confirmed in humans, the finding could help explain the drug’s powerful benefits and inspire more comprehensive treatments for obesity and diabetes.

Scientists discovered a surprising energy paradox in the brain during REM sleep, the stage most closely associated with dreaming. Blood supply to the brain begins increasing even before REM starts, but neurons’ immediately available energy, measured as ATP, then drops. The finding suggests that dreaming may require such intense internal processing that neurons consume energy faster than it can be replenished.

Scientists discovered rare flavoalkaloids in Cannabis leaves for the first time, along with dozens of other phenolic compounds that had never been reported in the plant. The findings suggest that Cannabis leaves, often discarded as waste, may contain a surprisingly rich source of potentially useful chemicals.

A major analysis suggests Phelan-McDermid syndrome, a genetic disorder closely linked to autism, may affect about 1 in 7,300 people and more than 45,000 Americans. Researchers warn that thousands of cases may remain hidden because genetic testing is often not performed, even as targeted treatments move into clinical trials.

Researchers used CRISPR to remove CD33 from donor stem cells, potentially giving doctors a way to attack aggressive blood cancers without destroying the healthy cells patients need after a transplant. In a 30-patient trial, the edited cells successfully took hold and appeared to shield blood cells from a CD33-targeted cancer treatment.

A magnet-producing bacterium extended the average lifespan of C. elegans worms by more than 43% while helping protect their neurological and intestinal health. Researchers traced much of the effect to suppression of ferroptosis, a damaging form of cell death linked to iron buildup and oxidative stress.

Scientists discovered a surprising backup system that lets mammalian cells make the essential amino acid cysteine even when the pathways once considered indispensable are disabled. The same survival mechanism may help cancer cells resist treatment, raising the possibility that shutting it down could make tumors easier to kill.

The brain may have a built-in way to quickly settle disagreements between regions processing the same scene. Researchers found that matching signals between two visual areas lasted longer, while conflicting signals rapidly faded away. This “consensus building” mechanism could help explain how the brain turns many specialized inputs into one unified view of the world.