Medical Bulletin 07/January/2026 - Video

Here are the top medical news for today:

Scientists uncover key reason behind frequent overlap of mental disorders

What if the boundaries between mental health disorders aren’t as clear-cut as we thought? A landmark genetics study published in Nature reveals that many psychiatric conditions share deep biological roots—suggesting that overlapping diagnoses may be more the rule than the exception. Led by the Psychiatric Genomics Consortium’s Cross-Disorder Working Group, this global project analyzed data from more than 6 million people, offering the most comprehensive view yet of how genetic factors connect 14 major mental health disorders.

For decades, diagnosing a mental illness has depended largely on symptoms and clinical observation rather than lab tests. Yet many patients diagnosed with one disorder—such as depression—often develop others like anxiety or substance dependence later in life. The new findings help explain why.

The team analyzed nearly one million individuals with psychiatric diagnoses and compared them to five million without. Using advanced genomic mapping, they identified 428 genetic variants linked to more than one disorder and pinpointed 101 “hot spots” on chromosomes where these shared variants clustered. Statistical models grouped the 14 disorders into five broad clusters—compulsive disorders, internalizing disorders, neurodevelopmental disorders, psychotic disorders, and substance-use disorders.

The results showed especially strong genetic ties between major depression, anxiety, and post-traumatic stress disorder, which shared roughly 90% of their genetic risk. Schizophrenia and bipolar disorder were also closely related, overlapping by about 66%. Further analysis revealed that the same genes often act in similar biological contexts—for example, genes active in oligodendrocytes (cells that insulate nerve fibers) were linked to mood disorders, while those in excitatory neurons were tied to schizophrenia and bipolar disorder.

Experts say these findings mark a turning point for psychiatry. Instead of viewing mental illnesses as distinct categories, this research highlights them as interconnected conditions with shared roots in our DNA. Future treatments, guided by genetic insights, could one day target these overlapping networks to better treat—and even prevent—multiple disorders at once.

REFERENCE: Andrew D. Grotzinger, Josefin Werme, et al.; Mapping the genetic landscape across 14 psychiatric disorders. Nature, 2025; DOI: 10.1038/s41586-025-09820-3

Experts bust popular myth about body reversing workout effects

Think your body cancels out the calories you burn by moving more? Think again. A new study published in Proceedings of the National Academy of Sciences reveals that physical activity truly adds to your daily energy output—without the body compensating by saving energy elsewhere. Led by scientists from Virginia Tech, the University of Aberdeen, and Shenzhen University, the research shows that every bit of movement—from walking the dog to marathon training—directly contributes to more calories burned overall.

Exercise has long been praised as vital for heart, brain, and metabolic health, but until now, scientists debated whether our total “energy budget” could actually expand with physical activity. One idea proposed that when we move more, our body pulls energy away from other systems, like digestion or temperature regulation, to keep calorie use stable. The rival theory—the additive model—suggests that moving more truly increases daily energy expenditure without taking away from other functions.

To test which model holds up, the research team studied 75 adults aged 19 to 63 with activity levels ranging from sedentary lifestyles to ultra-endurance training. Each participant’s daily energy use was measured using the gold-standard “doubly labeled water” technique—where participants drink water containing special forms of hydrogen and oxygen. By analyzing how quickly these isotopes left the body through breath and urine, scientists precisely calculated total daily calories burned over two weeks. Physical activity was tracked continuously using small waist-worn sensors.

The results were clear: people who moved more burned more energy, full stop. The body didn’t offset this by cutting back on other essential processes like heart function, breathing, or temperature regulation.

Interestingly, those who were more active also spent less time sitting, further boosting their calorie use. The findings support the additive energy model—meaning every bit of movement, no matter how small, truly counts. For maintaining energy balance and long-term health, more movement really does mean more calories burned.

REFERENCE: Kristen R. Howard, Olalla Prado-Nóvoa, Guillermo Zorrilla-Revilla, Eleni Laskaridou, Glen R. Reid, Elaina L. Marinik, Marina Stamatiou, Catherine Hambly, Brenda M. Davy, John R. Speakman, Kevin P. Davy. Physical activity is directly associated with total energy expenditure without evidence of constraint or compensation. Proceedings of the National Academy of Sciences, 2025; 122 (43) DOI: 10.1073/pnas.2519626122

Scientists discover method to help aging guts repair and heal naturally

Imagine if your gut could heal itself—even after years of wear and tear. Scientists at Cold Spring Harbor Laboratory (CSHL) have discovered a way to help aging intestines do just that using a powerful immune technology originally developed for cancer treatment. The study, published in Nature Aging found that CAR T-cell therapy can rejuvenate damaged intestinal tissue, reduce inflammation, and boost nutrient absorption in mice. Even more impressively, a single dose protected against radiation-induced damage and maintained gut health for up to a year.

As we age, our intestines lose their ability to repair themselves efficiently. The intestinal lining, or epithelium—a single layer of cells responsible for digestion and nutrient absorption—normally renews every few days. But with time or exposure to cancer treatments like radiation, this renewal process slows down, leading to inflammation and conditions such as “leaky gut.” The CSHL team set out to reverse that decline by targeting one of its underlying causes: senescent cells. These are aged cells that stop dividing yet refuse to die, releasing inflammatory molecules that damage surrounding tissue.

Amor Vegas and her team used a specially engineered form of immunotherapy known as anti-uPAR CAR T-cell therapy. Originally designed to fight senescent cells in metabolic diseases, these modified T cells were delivered directly into the guts of both young and old mice. The results were striking—treated animals showed faster healing of intestinal injuries, healthier epithelial linings, less inflammation, and improved nutrient uptake.

To test whether the therapy could protect against extreme damage, the team exposed mice to gut-harming radiation like that used in cancer therapy. Those given CAR T-cell treatment recovered dramatically better than untreated mice. Further experiments on human intestinal and colorectal cells produced similar results, suggesting strong potential for translation to clinical applications.

The findings hint at a future where CAR T-cell therapy could do more than fight cancer—it could also rejuvenate the body from the inside out, restoring one of its most vital organs.

REFERENCE: Onur Eskiocak, Joseph Gewolb, Vyom Shah, James A. Rouse, Saria Chowdhury, Erdogan O. Akyildiz, Inés Fernández-Maestre, Jacob A. Boyer, Aveline Filliol, Alexander S. Harris, Raditya Utama, Guangran Guo, Carolina Castro-Hernández, Emmanuella Nnuji-John, Charlie Chung, Arianna Anderson, Sara Flowers, Jill Habel, Paul B. Romesser, Ross L. Levine, Scott W. Lowe, Michel Sadelain, Semir Beyaz, Corina Amor. Anti-uPAR CAR T cells reverse and prevent aging-associated defects in intestinal regeneration and fitness. Nature Aging, 2025; DOI: 10.1038/s43587-025-01022-w