If you’re in your 60s or beyond, there’s good reason to pay close attention to how much Vitamin B12 you’re getting.

A lack of B12 is generally associated with anemia. That can significantly impact older adults because our bodies don’t absorb B12 as well, but also people who follow a vegan or vegetarian diet.

The danger for older adults who don’t get enough B12 includes a higher risk of cognitive decline, as well as brain lesions that may lead to dementia or stroke.

Maybe your doctor advises you to take a B12 vitamin supplement. That’s a good idea.

However, there is strong evidence that the current recommendations for how much B12 you should be getting fall far short of levels preventing this neurological decline.

Here’s what the research says…

Normal range B12 linked to cognitive decline, dementia and stroke

A new study led by UC San Francisco researchers found that older, healthy adults with lower concentrations of B12 showed signs of neurological and cognitive deficiency.

Importantly, this was true even when their B12 levels fell within the “normal” range.

The study subjects were 231 healthy adults without dementia or mild cognitive impairment (MCI). Their average age was 71. Their blood B12 amounts averaged 414.8 pmol/L, far above the minimum requirement of 148 pmol/L.

Cognitive testing revealed that people with lower active B12 levels had slower processing speed, indicating subtle cognitive decline. And the older the person, the worse the impact on processing speed.

People with low B12 also had slower visual processing speeds and slower brain connectivity, as indicated by their delayed responses to visual stimuli.

MRIs of these same adults revealed a higher volume of lesions in their white matter — the nerve fibers that enable communication between areas of the brain — which is often associated with cognitive decline as well as risk for dementia and stroke.

It’s time to reconsider how much B12 we need

The researchers have made one thing clear: it’s time to update the current recommendations for B12.

“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,” says senior author Dr. Ari Green of the UCSF Departments of Neurology and Ophthalmology.

“Revisiting the definition of B12 deficiency to incorporate functional biomarkers could lead to earlier intervention and prevention of cognitive decline.” This potential for early intervention empowers us to take control of our health and prevent potential issues.

Hopefully, the Food and Nutrition Board (FNB) at the National Academy of Medicine (NAM) — the institution responsible for setting Recommended Dietary Allowances for vitamins and determining what constitutes deficiency — will take note.

But if you’re an older adult like me, you probably find this as concerning as I do and might like to do something sooner rather than later.

Talk to your doctor for recommendations. They may want to test your blood levels before advising you on vitamin B12. Some doctors will prescribe vitamin B12 injections.

Otherwise, it’s generally a good idea to follow the recommendations made on the bottle of your supplement brand.

According to the Fact Sheet on vitamin B12, it has a low potential for toxicity. In fact, the FNB did not bother establishing a “tolerable upper limit” (UL) for B12. The UL is an amount not to be exceeded because of the heightened risk for toxicity. ULs vary per vitamin.

As a water-soluble vitamin (like Vitamin C), vitamin B12 is generally considered safe even at large doses because the body does not store excess amounts.

Remember to include foods rich in B12 in your diet, such as:

• Fish
• Red meat
• Poultry
• Eggs
• Milk and milk products
• Fortified breakfast cereals

Sources:

Low-Normal B12 Levels Linked to Slower Brain Processing — Neuroscience News

Vitamin B12 Levels Association with Functional and Structural Biomarkers of Central Nervous System Injury in Older Adults — Annals of Neurology

Are You Getting Enough Vitamin B12? What You Need to Know — Yale Medicine