Scientists Warn Current Vitamin B12 Guidelines May Be Too Low for Brain Health
Vitamin B12 is vital for brain and nerve health. However, new research shows that even “normal” levels may not be enough. Older adults with lower B12 levels showed slower thinking, more brain lesions, and subtle cognitive decline.
When Normal Isn’t Enough
The current daily requirement for B12 supports red blood cells and DNA production. However, researchers at UC San Francisco found that these guidelines may not protect the brain. Their study revealed that older adults with low-normal B12 performed worse on cognitive tests.
For example, participants with lower active B12 had slower visual processing speeds. MRIs also showed more white matter damage. This brain region helps different areas communicate, so damage can affect memory, focus, and reaction time. As a result, even levels considered safe may leave the brain vulnerable.
Rethinking B12 Deficiency
According to lead author Dr. Ari Green, current definitions of deficiency may be outdated. He explained that earlier studies often missed subtle signs of neurological damage. Therefore, revising the guidelines could help detect problems sooner and prevent decline.
Co-author Alexandra Beaudry-Richard added that older patients may benefit from supplements even if their test results appear normal. In addition, she stressed the need for more research on how B12 insufficiency harms the brain.
Vitamin B12 comes from animal foods like meat, fish, eggs, and dairy. Vegans and vegetarians can get it through fortified foods or supplements. Ensuring adequate intake could be a simple way to protect long-term brain health.
This study suggests that raising the threshold for deficiency may be necessary. It also highlights the importance of measuring active B12 rather than total levels. As scientists warn, keeping B12 truly “healthy” may help guard against cognitive decline in aging populations.
