When Body Fat Gets to Your Head
BMI may want to look away. Using whole-body MRI in nearly 26,000 UK Biobank participants, investigators mapped where body fat actually hangs out and found that its location had clear brain consequences. Six distinct fat distribution patterns emerged, and two stood out for all the wrong reasons: a pancreatic-predominant pattern and the misleadingly reassuring “skinny-fat” pattern, marked by relatively normal BMI but high visceral and ectopic fat. Compared with a lean reference group, both patterns were linked to smaller total and gray matter brain volumes, more white matter hyperintensities, poorer performance on cognitive tasks such as psychomotor speed and memory, and a higher prevalence of neurologic conditions, including mood disorders and stroke. Brain aging appeared to be accelerated in men with these high-risk profiles. So where fat is stored may matter more than how much there is, and MRI-based fat mapping may outperform BMI when it comes to flagging neurologic risk.
Source: Radiology
‘Just a Cold’ Isn’t So Simple
The common cold may feel routine, but a Yale School of Medicine study shows it’s anything but simple. Using primary human nasal epithelial cells, air–liquid interface cultures, and single-cell RNA sequencing, researchers found that rhinovirus infection was usually kept on a tight leash, with viral RNA detected in fewer than 2% of cells. That control came from fast, epithelial-intrinsic interferon responses, particularly type I and III interferons, which sharply limited viral replication. When interferon signaling was blocked, viral loads increased, more cell types became infected, and viral particles finally became visible on electron microscopy. Rhinovirus also triggered IL-1 signaling through the NLRP1 inflammasome, layering inflammation onto antiviral defense. Clinically, it helps explain why most colds stay mild—and why patients with impaired airway immunity may be more likely to tip into prolonged or severe respiratory illness, even from something we tend to dismiss as just a cold.
Source: Cell Press Blue
What Aging Bones Forgot to Feel
Turns out aging bones may be less about calcium deficiency and more about how they can’t feel the vibe anymore. In this mouse study from the University of Hong Kong, bone marrow stem cells needed the mechanosensing ion channel Piezo1 to stay on the bone-building path. Knock Piezo1 out, and the cells promptly chose fat instead—leading to lower bone volume, thinner cortices, fewer osteoblasts, and a noticeable expansion of bone marrow adiposity, while peripheral fat stayed the same. Exercise usually boosted trabecular bone and cut marrow fat, but without Piezo1, the skeleton basically shrugged and ignored the treadmill. Mechanistically, Piezo1 kept an inflammatory Ccl2–CCR2–lipocalin-2 loop under control via CaMKII and Klf2 signaling; lose that brake, and aging stem cells defaulted to adipogenesis. It’s a reminder that older bones may not just weaken—they stop listening.
Source: Signal Transduction and Targeted Therapy
Brewing Beliefs About Lactation
Anise—the licorice-scented darling of biscotti and teas—has long been promoted as a galactogogue, but the science remains more meh than magical. Anise seeds contain anethole, a phytoestrogen, plus a long guest list of bioactive compounds, some of which do transfer into breast milk. In lactating women given 100 mg of trans-anethole, measurable milk levels appeared within 2 hours and peaked modestly, explaining why milk can take on a faint anise aroma. Clinical evidence for boosting milk supply is limited: a meta-analysis found only a small increase in milk volume on postpartum day 1 and low-certainty benefit by day 7, with no consistent effects on infant weight gain. Safety-wise, anise is generally recognized as safe as a flavoring, but excess intake—particularly via herbal teas marketed for lactation—has been linked to elevated maternal liver enzymes and reversible toxicity in breastfed neonates, likely due to anethole. Bottom line: anise-containing products shouldn’t replace proper lactation assessment, dosing matters, and “natural” doesn’t always mean harmless—especially when the teapot gets heavy-handed.
Source: Drugs and Lactation Database
A Gender Gap in AI Confidence
In a wide-ranging survey study, researchers asked a simple question with a very modern twist: why are women more skeptical than men about AI at work? Spoiler alert: it’s not about hating tech; it’s about weighing risk. Surveying about 3,000 adults in the US and Canada, women were roughly 11% more likely to say AI’s risks outweigh its benefits, mirroring classic gender gaps seen in attitudes toward trade. Two reasons stood out: women tended to be more risk-averse overall and were more likely to work in roles vulnerable to automation. When participants were told that AI adoption might, or might not, lead to net job gains, support fell across the board, but women’s support dropped faster as certainty declined, landing about 13% lower than men’s in the riskiest scenario. Open-ended responses sealed the deal: women voiced more uncertainty or doubt about benefits, while men waxed optimistic about efficiency and productivity. For physicians navigating AI’s rapid clinical creep, the takeaway is clear: confidence loves certainty, and ignoring uneven risk exposure may turn innovation excitement into side-eye.
Source: PNAS Nexus
