People who regularly use marijuana experience changes in their brain structure and function, but it’s not clear that cannabis is the cause, a new study finds. Researchers found specific differences in the brains of people who’d ever used weed, particularly in areas densely packed with cannabinoid receptors. However, genetic analysis couldn’t pin down any specific association between cannabis use and these brain changes. This means some other factor besides weed might be causing these brain changes in marijuana users. “Our results need to be interpreted with careful consideration,” concluded the research team led by Saba Ishrat, a doctoral student in psychiatry with the University of Oxford in the U.K. “Additional research is needed to understand the effects of heavy cannabis use in this population, including considerations of potency and related information, to inform public policy.” For the study, researchers analyzed data on nearly 15,900 weed users participating in the U.K. Biobank research project for whom genetic profiling and MRI brain scans were available. Looking at the brains of the marijuana users, researchers found that they had poorer integrity of their “white matter,” the part of the brain that connects different brain regions. This was particularly evident in the corpus callosum, which serves as the main route of communication between the left and right sides of the brain. Weed users also had weaker neural connections in…  read on >  read on >

For many reasons, bodybuilders and others involved in weight training might have to take a break from the gym. However, new Finnish research finds that even weeks-long interruptions in training won’t hamper muscle-building efforts. “Of course, the break slows progress some, but it is comforting to know that it is possible to reach the pre-break level surprisingly quickly,” said study lead author Eeli Halonen. He’s a doctoral student in sport and health sciences at the University of Jyväskylä. Halonen and his colleagues published their findings recently in the Scandinavian Journal of Medicine and Science in Sports. In the new study, 42 adults (just over half were males) took part in one of two 20-week weight-training regimens. In one group, folks engaged in weight-training sessions (exercises included leg presses and biceps curls) for the whole 20 weeks without interruption. The second group exercised for 10 weeks, then took a 10-week break, then resumed exercise for another 10 weeks. “Results for maximum strength and muscle size development were similar in both groups,” the researchers concluded in a university news release. For the 20 people that took the 10-week break midway, all measures of muscle improvement bounced back quickly, Halonen’s group said. “During the first few weeks after the break, progress was very rapid and after only five weeks of re-training, the pre-break level had already been reached,”…  read on >  read on >

Smoking marijuana during pregnancy may quell your morning sickness, but it could also harm your child’s development, a new study warns. Cannabis exposure in the womb is associated in early childhood with poorer thinking skills, researchers reported Oct. 28 in the journal JAMA Pediatrics. These kids also have behavioral problems like impulse control, poor attention and aggressive behavior, researchers found. “Although cannabis is a natural product, there are still many risks to using it during pregnancy,” said lead researcher Sarah Keim, principal investigator in the Center for Biobehavioral Health at Nationwide Children’s Hospital in Ohio. “Some women may turn to cannabis to help deal with some common issues of pregnancy including nausea, sleep problems and stress,” Keim said. “This is not recommended. Consulting with a health care provider to find safer options to help with these issues during pregnancy is important.” For the study, researchers combined multiple assessment tools to track the development of preschool children. Kids exposed to weed during pregnancy had more difficulty controlling their impulses, paying attention and planning, based on observations of their behavior in a play laboratory environment. They also tended to show more aggressive behavior. “Our findings were not surprising — they actually confirm and expand on longstanding evidence from previous research,” Keim said in a hospital news release. “With our more contemporary and diverse sample of women and…  read on >  read on >

As the popularity of GLP-1 meds like Wegovy and Zepbound grows, fewer Americans are turning to weight-loss surgeries to trim their waistlines, a new report finds. Prescriptions of this GLP-1 class of diabetes and weight-loss medications more than doubled between 2022 and 2023, a new tally finds. “In contrast, there was a 25.6% decrease in patients undergoing metabolic bariatric surgery” during the same time period, reported a team led by Dr. Thomas Tsai, an assistant professor of surgery at Harvard Medical School in Boston. Since the U.S. Food and Drug Administration approved Wegovy (the first GLP-1 medicine aimed at weight loss) in mid-2021, sales of the drug and related GLP-1 meds such as Ozempic, Mounjaro and Zepbound have soared. Rapid weight loss has been a hallmark of these medications, which work, in part, by making folks feel full earlier. Prior to the advent of GLP-1s, diet and exercise or bariatric surgeries were the main routes to weight loss for obese Americans. However, the “Ozempic era” may have changed all that, Tsai’s team said. “Anecdotally, health systems have closed hospital-based metabolic bariatric surgery programs due to decreased demand,” they noted in the introduction to their study. To get at harder numbers, the researchers tracked data from the medical records of more than 17 million Americans insured via private coverage or Medicare Advantage. All patients were non-diabetic but…  read on >  read on >

Texts deliver rapid-fire messages, but a new study indicates human brains can keep up with the barrage. The brain can detect the basic linguistic structure of a brief sentence in roughly 150 milliseconds — about the speed of a blink of an eye, researchers report. “Our experiments reveal that the brain’s language comprehension system may be able to perceive language similarly to visual scenes, whose essence can be grasped quickly from a single glance,” said lead researcher Liina Pylkkanen, a professor in New York University’s Department of Linguistics and Department of Psychology. In essence, text or images can be taken in and processed much more quickly than anything someone might say to a person, researchers said. “The human brain’s processing capacity for language may be much faster than what we might think,” Pylkkanen said in a university news release. “In the amount of time it takes to hear one syllable, the brain can actually detect the structure of a short sentence.”   The rise of email, followed by texts and social media, has promoted a quick and fragmented consumption of information, researchers said. Short messages are constantly flashing at people through phone notifications and online platforms. “This shift has made it clear that our brains not only have the ability to instinctively process rapid messages, but can also make snap decisions based on them — like…  read on >  read on >