“Hearst Magazines and Yahoo may earn commission or revenue on some items through these links.” While vitamin B12 might not be as buzzy as calcium or an immediately recognizable household name like Vitamin C or D, it’s just as important for your health—and particularly your brain health. This water-soluble vitamin plays a role in a whole bunch of processes in your body, helping produce your DNA, red blood cells, and generate energy, among other things. But new research suggests we may not be getting enough B12, which could actually raise your risk of developing dementia in the future. Here’s what neurologists and a dietitian want you know about Vitamin B12, plus its potential impact on your current and future brain health. Meet the experts: Amit Sachdev, MD, MS, medical director in the Department of Neurology at Michigan State University; Jessica Cording, RD, author of The Little Book of Game-Changers; Clifford Segil, DO, neurologist at Providence Saint John’s Health Center in Santa Monica, CA
What did the study find?
For the study, which was published in February in the Annals of Neurology, researchers recruited 231 healthy older people without dementia or mild cognitive impairment (which is considered a precursor to dementia). All of the participants had B12 levels in their blood that averaged 414.8 pmol/L, which is significantly above the established minimum level of 148 pmol/L (anything below this is considered “deficient,” the study explains). The researchers drilled down on the data to focus on a biologically active component of vitamin B12, which indicates the amount of B12 the body can actually use. They found that participants with lower active levels of B12 experienced slower processing speed and responded slower to visual stimuli, which suggests that they had slower visual processing speed and slower electrical impulses in the brain. These impacts became even more apparent in older participants. During participant MRIs, researchers found that those with lower levels of B12 had a more lesions on their brain’s white matter, which may be linked to dementia and cognitive decline. The study concluded that the findings should “challenge” current B12 recommendations.
What are current B12 recommendations?
The current recommended intake for B12 varies by age and depends on whether you’re pregnant or breastfeeding. However, most adults aged 19 and up are told to aim to get 2.4 micrograms of B12 a day, according to the National Institutes of Health (NIH). (If you’re pregnant, that increases to 2.6 micrograms, while breastfeeding raises it to 2.8 micrograms.) But as the study points out, this may not actually be sufficient to protect brain health.
What is the ideal B12 range to aim for?
The study doesn’t say what recommended B12 levels should be, just that its possible some people aren’t getting enough, and that more research is needed in this area to figure out optimal levels.
Right now, the best way to know if you’re hitting a good B12 range for your body is to get a blood test, says Jessica Cording, RD, author of The Little Book of Game-Changers. The cut-off between normal and deficient vitamin B12 blood levels varies by lab, but anything lower than 200 or 250 pg/mL is usually considered deficient, according to the NIH. However, there are other markers that can suggest you’re low in B12, so it’s really best to talk to your healthcare provider about your results if you get tested. Cording points out that some healthcare providers will say you’re levels are good, even if you’re on the low end of the “normal” range. “I like to see people in the middle of the range with labs for B12,” she says. “There’s ‘normal’ and then there’s ‘optimal.’” Someone within “normal” B12 limits, might do fine with taking their B12 in a multivitamin, Cording says. “If they have a noted deficiency, I might put them on a higher dose—500 micrograms or 1000 micrograms—and see how they feel.”
How does B12 help brain function?
B12 does a few different things in the brain. For one, it helps turn sugar into energy. “Our brains run on sugar. Vitamin B12 is important for processing that sugar into energy,” explains Amit Sachdev, MD, MS, medical director in the Department of Neurology at Michigan State University. “Low B12 levels can lead to mental fog.” B12 is also needed for optimal cell function and red blood cell formation, Cording points out. “All of these things can impact cognition,” she adds. Cording says she’ll often recommend that patients have their B12 levels tested if they’re feeling slower than usual, tired, or feeling down and they don’t know why. Symptoms of low B12 levels can also mimic signs of dementia. “I check a B12 level in all the patients I see with memory loss,” says Clifford Segil, DO, neurologist at Providence Saint John’s Health Center in Santa Monica, CA. Segil also says that B12 is “great for general health and it does help to give people energy.” Segil says that more research is needed, but is in support of the new findings. “An intervention that involves better nutrition is something that every neurologist would like to focus on,” he says.
Can I get B12 from my regular diet?
Yup, you can get B12 in your diet. These foods have higher levels of B12, per the NIH:
Beef liver, 70.7 micrograms
Clams, 17 micrograms
Oysters, 14.9 micrograms
Nutritional yeast, 8.3 to 24 micrograms
Salmon, 2.6 micrograms
Tuna, 2.5 micrograms
Dairy products and some breakfast cereals also contain B12, but “it’s primarily in animal products,” Cording says.
What kind of B12 supplements are best?
If you’re considering going on a B12 supplement, it’s a good idea to check in with a healthcare provider first. “A lab test is always a great place to start, because then you know how high the dose should be,” Cording says. Most people do well with a capsule, but you can also get B12 in a tablet that dissolves under your tongue, she says. If you have trouble absorbing B12, you may need to get an infusion via IV. But, again, if you suspect that low levels of B12 are an issue, talk to your healthcare provider. They can do a thorough check to see what could be behind your symptoms and figure out next steps from there.
