30/04/2025
As I have always thought about b12 reference ranges.
New research suggests that current vitamin B12 guidelines might be outdated, as even “normal” levels could still risk optimal brain function, with scientists warning that a subtle cognitive decline linked to B12 insufficiency might affect more people than expected.
A study led by researchers at the University of California, San Francisco (UCSF) found that healthy older adults with lower B12 levels showed more signs of neurological and cognitive decline. These people had more damage to the brain’s white matter and performed worse on tests measuring cognitive and visual processing speeds, compared to those with higher B12 levels.
Senior study author Dr. Ari J. Green, from UCSF’s Departments of Neurology and Ophthalmology and the Weill Institute for Neurosciences, says the findings raise concerns about current B12 recommendations.
“Previous studies that defined healthy amounts of B12 may have missed subtle functional manifestations of high or low levels that can affect people without causing overt symptoms,” said Green. “Revisiting the definition of B12 deficiency to incorporate functional biomarkers could lead to earlier intervention and prevention of cognitive decline.”
In the study, researchers enrolled 231 healthy participants without dementia or mild cognitive impairment, whose average age was 71. They were recruited through the Brain Aging Network for Cognitive Health (BrANCH) study at UCSF. Their blood B12 amounts averaged 414.8 pmol/L, well above the accepted minimum of 148 pmol/L. Participants with lower active B12 were found to have slower processing speed, relating to subtle cognitive decline. Such impact was amplified by older age. They also showed significant delays responding to visual stimuli, indicating slower visual processing speeds and generally slower brain conductivity. MRI revealed a higher volume of lesions in the participants’ white matter, which may be associated with cognitive decline, dementia or stroke.
“In addition to redefining B12 deficiency, clinicians should consider supplementation in older patients with neurological symptoms even if their levels are within normal limits,” co-first author Alexandra Beaudry-Richard said. “Ultimately, we need to invest in more research about the underlying biology of B12 insufficiency, since it may be a preventable cause of cognitive decline.”
These days, many biomedical scientists are speaking the same language as natural therapists.
For more information see: https://scitechdaily.com/scientists-just-found-a-major-problem-with-vitamin-b12-guidelines-and-your-brain-might-be-at-risk/