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Medscape
27-05-2025
- Health
- Medscape
Vitamin D Especially Important for Women's Brain Health
LOS ANGELES — Vitamin D is important for brain health, but this might be particularly true for women but doesn't appear to have this beneficial effect in men, early research suggested. The large study showed an association between greater plasma vitamin D levels in females and better memory and larger subcortical brain structures. 'We found that vitamin D for women was correlated with better cognitive outcomes, but we need to do more research to find out what role vitamin D actually plays at a mechanistic level,' study investigator Meghan Reddy, MD, Psychiatry Resident, UCLA Semel Institute for Neuroscience and Human Behavior, Los Angeles, told Medscape Medical News . The findings were presented here at the American Psychiatric Association (APA) 2025 Annual Meeting. Protective Effects This latest study added to the growing body of literature of research on vitamin D and brain health. Previous studies have shown that vitamin D may influence cognition and brain function in older adults, potentially through its anti-inflammatory, antioxidant, and neuroprotective effects. Research also suggested it may promote brain health by increasing neurotrophic factors and aiding in the clearance of amyloid from the brain. Recent findings published in the American Journal of Clinical Nutrition suggested that vitamin D may also affect biological aging by preserving telomeres — the protective caps at the ends of chromosomes that shorten with age. Other research has also shown telomere length may help protect against brain diseases, including a study previously reported by Medscape Medical News , which linked longer leukocyte telomere length to a lower risk for stroke, dementia, and late-life depression. Meghan Reddy, MD In the current study, Reddy and colleagues used data from the multisite Human Connectome Project to track individuals over time to understand age-related changes in brain structure, function, and connectivity. They are investigating various biomarkers that might correlate with aging, including hemoglobin, creatine, glycated hemoglobin (for blood glucose levels), high-density lipoprotein, and low-density lipoprotein, in addition to vitamin D. The idea, said Reddy, is to track cognitive health using biomarkers in addition to brain imaging and cognitive testing. The study included 1132 individuals, 57% of whom were women and 66% of whom were White. The average age was approximately 62 years, with participants ranging from 36 to 102 years old. Participants underwent neuropsychological testing to assess short-term memory and fluid intelligence — the capacity to reason and solve problems, which is closely linked to comprehension and learning. They also provided blood samples and underwent MRI scans. Researchers divided participants into two age groups: those younger than 65 years and those 65 years or older. The investigators found a significant association between vitamin D levels and memory in women ( P = .04). Sex Differences 'What's interesting is that when we looked specifically at memory, higher vitamin D levels were linked to better memory performance — but only in women, not men,' said Reddy, adding that she found this somewhat surprising. In women, investigators found a significant association between vitamin D levels and the volume of the putamen ( P = .05) and pallidum ( P = .08), with a near-significant trend for the thalamus. In contrast, studies show that in men, higher vitamin D levels were associated with smaller volumes of the thalamus, putamen, and pallidum. There were no differences in the impact of vitamin D by age group. Sex differences in the relationship between vitamin D, cognition, and brain volume warrant further investigation, Reddy said. She also noted that the study is correlational, examining memory, brain volume, and vitamin D levels at a single timepoint, and therefore it can only offer a hypothesis. Future studies will include multiple time points to explore these relationships over time. The results did not determine an ideal vitamin D plasma level to promote brain health in women. Commenting on the research for Medscape Medical News , Badr Ratnakaran, MD, a geriatric psychiatrist in Roanoke, Virginia, and chair of the APA's Council on Geriatric Psychiatry, said the finding that women may get more brain benefits from vitamin D than men is 'key' because dementia is more prevalent among women since they tend to live longer. Other research has shown vitamin D may help manage depression in older women, which makes some sense as dementia and depression 'go hand in hand,' he said. Ratnakaran recommended that women take a vitamin supplement only if they're deficient, as too much vitamin D can lead to kidney stones and other adverse side effects.
CNN
29-01-2025
- Health
- CNN
More frequent marijuana use may damage brain's ability to remember an important memory skill
More frequent use of marijuana damages the brain's working memory, which could lead to issues with safety, communications and work success, a new study found. 'Working memory is the ability to retain information for a short period of time and use it,' said lead study author Joshua Gowin, an assistant professor of radiology at the University of Colorado's Anschutz School of Medicine in Aurora, Colorado. 'An example is checking your blind spot when driving down the road,' Gowin said. 'When you look back in front of you, you need to remember what you saw in the blind spot before you can make a good decision if you want to change lanes or not. 'When you're in the middle of a conversation with your boss, you need to remember what they said long enough to respond to it,' Gowin said. 'Losing working memory means that retaining that information might require more effort and be more challenging.' Only a connection, not cause and effect The new observational study, published Tuesday in the journal JAMA Network Open, cannot prove that cannabis harms the brain, said Carol Boyd, professor emerita and founding director of the Center for the Study of Drugs, Alcohol, Smoking and Health at the University of Michigan in Ann Arbor. She was not involved in the study. However, the study does add scientific evidence to long-standing social beliefs about regular cannabis use, Boyd said in an email. 'For years, clinicians, family and friends who knew heavy cannabis users understood that their memories were 'shot' — there's even a term for this, 'stoner,' as in 'forgot the grocery list, couldn't follow a recipe, couldn't get it together,'' she said. However, the study could not determine if working memory comes back if a heavy user quits and is a nonuser for an extended period of time, she added. 'Can the adolescent who used cannabis more than 1000 times between the ages of 15 and 20 years of age, but stopped using at 20 years, demonstrate improved working memory 10 years later?' Boyd said via email. 'That is my 64-dollar question — where is the hope for the person with a chronic use disorder who wants their memory back?' More frequent use mattered most The study analyzed data from the Human Connectome Project, which gathers raw data from studies that focus on how age, development, disease and other factors impact the brain. In what researchers are calling the largest dataset used to study cannabis and brain function, over 1,000 former or current cannabis users underwent brain scans while completing seven different types of cognitive tests between 2012 and 2015. Those tests measured their working memory, how they used emotion and rewards in their thinking, and how the brain responded to language. In addition, researchers tested how the brain handled motor skills, as well as how each person's brain responded to others in a social setting. Study participants, who were between 22 and 36 years of age, provided urine samples on the day of testing to assess recent use. Tetrahydrocannabinol, or THC, which is what provides the euphoria associated with cannabis use, can be detected 'for up to 2 weeks in the casual user and possibly longer in the chronic user,' according to the US Centers for Disease Control and Prevention. Individuals were considered heavy cannabis users if they had used marijuana more than 1,000 times in their lives; moderate users if they had used weed between 10 and 999 times; and nonusers if their use was less than 10 times. Researchers found cannabis use reduced brain activity in certain areas of the brain responsible for decision-making, memory, paying attention and emotional processing. However, the only test that reached statistical significance was working memory, such as remembering a shopping list or following verbal instructions. Researchers found 63% of heavy lifetime cannabis users exhibited reduced brain activity during a working memory task, while 68% of people who tested positive for recent use of cannabis also demonstrated a similar impact. 'However, when we compared recent to chronic users of cannabis side by side, we found that chronic use seemed to be more important than recent use when it came to problems with working memory,' Gowin said. The reduction in brain activation for heavy users relative to non-users was approximately 14%,' he said. The study did not know the time frame for heavy cannabis use — were all the 1,000 uses in someone's early 20s and they then had abstained for 10 years? Or had they become recent heavy users? 'Even if a chronic user had stopped using, they still showed cognitive decline in working memory,' he said. 'So it did not seem to be contingent upon recent use, but it was related more to chronic use across their lifetime.' Outstanding questions Heavy cannabis users in the study tended to be male, with a lower educational and social economic status, and were more likely to be smokers and drink alcohol. 'However, we did include alcohol in our statistical models, and we found that alcohol did not explain the effects we saw, while cannabis use did,' Gowin said. However, the study was unable to determine levels of THC in the marijuana that was used or control for existing psychological conditions such as ADHD, which is also known to impact working memory, Boyd said. 'It is possible that ADHD is a confounder, distorting the results between heavy cannabis use and impaired working memory, she added. 'Young adults with ADHD are disproportionately represented among cannabis users. 'The amount of THC ingested, and the mode of ingestion were not provided,' Boyd said, so there is no way to know 'how much THC is involved in chronic, heavy use.' While it's true that researchers were unable to determine if the cannabis was smoked, vaped or eaten, the study was conducted prior to 2015 when smoking marijuana was most common, Gowin said. 'And certainly smoking or inhaling cannabis means it crosses the blood-brain barrier more quickly than if you consume an edible,' he said. So what's the answer to Boyd's $64 question: Will regular cannabis users get their working memory back? It's just too soon to know, Gowin said. 'Some really interesting studies have paid people to stop using cannabis for a period of time, usually a month, and there's some evidence that they recover some of their memory function over that time,' he said. 'And there is some evidence that a period of abstinence from alcohol can lead to recovery of brain tissue,' Gowin added. 'But when it comes to chronic marijuana use and the brain, it's an area in which investigation is ongoing. Right now we just don't know.'
CNN
28-01-2025
- Health
- CNN
More frequent marijuana use may damage brain's ability to remember an important memory skill
More frequent use of marijuana damages the brain's working memory, which could lead to issues with safety, communications and work success, a new study found. 'Working memory is the ability to retain information for a short period of time and use it,' said lead study author Joshua Gowin, an assistant professor of radiology at the University of Colorado's Anschutz School of Medicine in Aurora, Colorado. 'An example is checking your blind spot when driving down the road,' Gowin said. 'When you look back in front of you, you need to remember what you saw in the blind spot before you can make a good decision if you want to change lanes or not. 'When you're in the middle of a conversation with your boss, you need to remember what they said long enough to respond to it,' Gowin said. 'Losing working memory means that retaining that information might require more effort and be more challenging.' Only a connection, not cause and effect The new observational study, published Tuesday in the journal JAMA Network Open, cannot prove that cannabis harms the brain, said Carol Boyd, professor emerita and founding director of the Center for the Study of Drugs, Alcohol, Smoking and Health at the University of Michigan in Ann Arbor. She was not involved in the study. However, the study does add scientific evidence to long-standing social beliefs about regular cannabis use, Boyd said in an email. 'For years, clinicians, family and friends who knew heavy cannabis users understood that their memories were 'shot' — there's even a term for this, 'stoner,' as in 'forgot the grocery list, couldn't follow a recipe, couldn't get it together,'' she said. However, the study could not determine if working memory comes back if a heavy user quits and is a nonuser for an extended period of time, she added. 'Can the adolescent who used cannabis more than 1000 times between the ages of 15 and 20 years of age, but stopped using at 20 years, demonstrate improved working memory 10 years later?' Boyd said via email. 'That is my 64-dollar question — where is the hope for the person with a chronic use disorder who wants their memory back?' More frequent use mattered most The study analyzed data from the Human Connectome Project, which gathers raw data from studies that focus on how age, development, disease and other factors impact the brain. In what researchers are calling the largest dataset used to study cannabis and brain function, over 1,000 former or current cannabis users underwent brain scans while completing seven different types of cognitive tests between 2012 and 2015. Those tests measured their working memory, how they used emotion and rewards in their thinking, and how the brain responded to language. In addition, researchers tested how the brain handled motor skills, as well as how each person's brain responded to others in a social setting. Study participants, who were between 22 and 36 years of age, provided urine samples on the day of testing to assess recent use. Tetrahydrocannabinol, or THC, which is what provides the euphoria associated with cannabis use, can be detected 'for up to 2 weeks in the casual user and possibly longer in the chronic user,' according to the US Centers for Disease Control and Prevention. Individuals were considered heavy cannabis users if they had used marijuana more than 1,000 times in their lives; moderate users if they had used weed between 10 and 999 times; and nonusers if their use was less than 10 times. Researchers found cannabis use reduced brain activity in certain areas of the brain responsible for decision-making, memory, paying attention and emotional processing. However, the only test that reached statistical significance was working memory, such as remembering a shopping list or following verbal instructions. Researchers found 63% of heavy lifetime cannabis users exhibited reduced brain activity during a working memory task, while 68% of people who tested positive for recent use of cannabis also demonstrated a similar impact. 'However, when we compared recent to chronic users of cannabis side by side, we found that chronic use seemed to be more important than recent use when it came to problems with working memory,' Gowin said. The reduction in brain activation for heavy users relative to non-users was approximately 14%,' he said. The study did not know the time frame for heavy cannabis use — were all the 1,000 uses in someone's early 20s and they then had abstained for 10 years? Or had they become recent heavy users? 'Even if a chronic user had stopped using, they still showed cognitive decline in working memory,' he said. 'So it did not seem to be contingent upon recent use, but it was related more to chronic use across their lifetime.' Outstanding questions Heavy cannabis users in the study tended to be male, with a lower educational and social economic status, and were more likely to be smokers and drink alcohol. 'However, we did include alcohol in our statistical models, and we found that alcohol did not explain the effects we saw, while cannabis use did,' Gowin said. However, the study was unable to determine levels of THC in the marijuana that was used or control for existing psychological conditions such as ADHD, which is also known to impact working memory, Boyd said. 'It is possible that ADHD is a confounder, distorting the results between heavy cannabis use and impaired working memory, she added. 'Young adults with ADHD are disproportionately represented among cannabis users. 'The amount of THC ingested, and the mode of ingestion were not provided,' Boyd said, so there is no way to know 'how much THC is involved in chronic, heavy use.' While it's true that researchers were unable to determine if the cannabis was smoked, vaped or eaten, the study was conducted prior to 2015 when smoking marijuana was most common, Gowin said. 'And certainly smoking or inhaling cannabis means it crosses the blood-brain barrier more quickly than if you consume an edible,' he said. So what's the answer to Boyd's $64 question: Will regular cannabis users get their working memory back? It's just too soon to know, Gowin said. 'Some really interesting studies have paid people to stop using cannabis for a period of time, usually a month, and there's some evidence that they recover some of their memory function over that time,' he said. 'And there is some evidence that a period of abstinence from alcohol can lead to recovery of brain tissue,' Gowin added. 'But when it comes to chronic marijuana use and the brain, it's an area in which investigation is ongoing. Right now we just don't know.'
CNN
28-01-2025
- Health
- CNN
More frequent marijuana use may damage brain's ability to remember an important memory skill
More frequent use of marijuana damages the brain's working memory, which could lead to issues with safety, communications and work success, a new study found. 'Working memory is the ability to retain information for a short period of time and use it,' said lead study author Joshua Gowin, an assistant professor of radiology at the University of Colorado's Anschutz School of Medicine in Aurora, Colorado. 'An example is checking your blind spot when driving down the road,' Gowin said. 'When you look back in front of you, you need to remember what you saw in the blind spot before you can make a good decision if you want to change lanes or not. 'When you're in the middle of a conversation with your boss, you need to remember what they said long enough to respond to it,' Gowin said. 'Losing working memory means that retaining that information might require more effort and be more challenging.' Only a connection, not cause and effect The new observational study, published Tuesday in the journal JAMA Network Open, cannot prove that cannabis harms the brain, said Carol Boyd, professor emerita and founding director of the Center for the Study of Drugs, Alcohol, Smoking and Health at the University of Michigan in Ann Arbor. She was not involved in the study. However, the study does add scientific evidence to long-standing social beliefs about regular cannabis use, Boyd said in an email. 'For years, clinicians, family and friends who knew heavy cannabis users understood that their memories were 'shot' — there's even a term for this, 'stoner,' as in 'forgot the grocery list, couldn't follow a recipe, couldn't get it together,'' she said. However, the study could not determine if working memory comes back if a heavy user quits and is a nonuser for an extended period of time, she added. 'Can the adolescent who used cannabis more than 1000 times between the ages of 15 and 20 years of age, but stopped using at 20 years, demonstrate improved working memory 10 years later?' Boyd said via email. 'That is my 64-dollar question — where is the hope for the person with a chronic use disorder who wants their memory back?' More frequent use mattered most The study analyzed data from the Human Connectome Project, which gathers raw data from studies that focus on how age, development, disease and other factors impact the brain. In what researchers are calling the largest dataset used to study cannabis and brain function, over 1,000 former or current cannabis users underwent brain scans while completing seven different types of cognitive tests between 2012 and 2015. Those tests measured their working memory, how they used emotion and rewards in their thinking, and how the brain responded to language. In addition, researchers tested how the brain handled motor skills, as well as how each person's brain responded to others in a social setting. Study participants, who were between 22 and 36 years of age, provided urine samples on the day of testing to assess recent use. Tetrahydrocannabinol, or THC, which is what provides the euphoria associated with cannabis use, can be detected 'for up to 2 weeks in the casual user and possibly longer in the chronic user,' according to the US Centers for Disease Control and Prevention. Individuals were considered heavy cannabis users if they had used marijuana more than 1,000 times in their lives; moderate users if they had used weed between 10 and 999 times; and nonusers if their use was less than 10 times. Researchers found cannabis use reduced brain activity in certain areas of the brain responsible for decision-making, memory, paying attention and emotional processing. However, the only test that reached statistical significance was working memory, such as remembering a shopping list or following verbal instructions. Researchers found 63% of heavy lifetime cannabis users exhibited reduced brain activity during a working memory task, while 68% of people who tested positive for recent use of cannabis also demonstrated a similar impact. 'However, when we compared recent to chronic users of cannabis side by side, we found that chronic use seemed to be more important than recent use when it came to problems with working memory,' Gowin said. The reduction in brain activation for heavy users relative to non-users was approximately 14%,' he said. The study did not know the time frame for heavy cannabis use — were all the 1,000 uses in someone's early 20s and they then had abstained for 10 years? Or had they become recent heavy users? 'Even if a chronic user had stopped using, they still showed cognitive decline in working memory,' he said. 'So it did not seem to be contingent upon recent use, but it was related more to chronic use across their lifetime.' Outstanding questions Heavy cannabis users in the study tended to be male, with a lower educational and social economic status, and were more likely to be smokers and drink alcohol. 'However, we did include alcohol in our statistical models, and we found that alcohol did not explain the effects we saw, while cannabis use did,' Gowin said. However, the study was unable to determine levels of THC in the marijuana that was used or control for existing psychological conditions such as ADHD, which is also known to impact working memory, Boyd said. 'It is possible that ADHD is a confounder, distorting the results between heavy cannabis use and impaired working memory, she added. 'Young adults with ADHD are disproportionately represented among cannabis users. 'The amount of THC ingested, and the mode of ingestion were not provided,' Boyd said, so there is no way to know 'how much THC is involved in chronic, heavy use.' While it's true that researchers were unable to determine if the cannabis was smoked, vaped or eaten, the study was conducted prior to 2015 when smoking marijuana was most common, Gowin said. 'And certainly smoking or inhaling cannabis means it crosses the blood-brain barrier more quickly than if you consume an edible,' he said. So what's the answer to Boyd's $64 question: Will regular cannabis users get their working memory back? It's just too soon to know, Gowin said. 'Some really interesting studies have paid people to stop using cannabis for a period of time, usually a month, and there's some evidence that they recover some of their memory function over that time,' he said. 'And there is some evidence that a period of abstinence from alcohol can lead to recovery of brain tissue,' Gowin added. 'But when it comes to chronic marijuana use and the brain, it's an area in which investigation is ongoing. Right now we just don't know.'
