This vitamin deficiency can cause forgetfulness and mimic symptoms of dementia—but it’s reversible. Doctors explain the signs to look for

Approximately 5.8 million people in the United States suffer from Alzheimer’s disease and related dementias, giving these life-threatening illnesses a significant impact across the country. But while it can be devastating when a loved one shows signs of memory loss, doctors say you shouldn’t automatically assume they have dementia.

Several factors can cause classic signs of dementia to appear, including a vitamin B12 deficiency. “Vitamin B12 deficiency can lead to cognitive impairment, including impaired thinking,” says Dr. Scott Kaiser, geriatrician and director of geriatric cognitive health at the Pacific Neuroscience Institute in Santa Monica, California. “It can definitely mimic the signs of dementia.”

Add to that the fact that older people are more likely to have trouble fully absorbing vitamin B12, putting them at risk for deficiency, and doctors say that vitamin B12 deficiency should at least be on the cards. radar of people with older relatives. Unlike dementia, it is a health problem that can be reversed.

But what does vitamin B12 deficiency look like and how can it be distinguished from dementia? The doctors explain.

What is vitamin B12?

Vitamin B12 is a water-soluble vitamin naturally found in some foods, although it is also available as a dietary supplement and prescription drug, according to the National Institutes of Health (NIH). This vitamin helps your body make DNA and also plays a role in the development and function of the central nervous system, which includes the brain and spinal cord.

Your body can’t produce vitamin B12, so you must get it from outside sources like meat, dairy, eggs, fortified foods and supplements, according to the NIH. Most adults need 2.4 micrograms of vitamin B12 per day, although these numbers are slightly higher during pregnancy and breastfeeding.

Causes of vitamin B12 deficiency

There are several reasons why a person may develop a vitamin B12 deficiency. Following a vegan diet for years is a big task, says Deborah Cohen, DCN, associate professor in the department of clinical and preventive nutrition sciences at Rutgers University School of Health Professions. “Humans can store a small amount of vitamin B12,” so it can take a while for a deficiency to appear, she explains.

But Cohen says there are many other risk factors for vitamin B12 deficiency, including taking the diabetes drug metformin and certain gastroesophageal reflux disease (GERD) medications, like blood pressure inhibitors. proton pump, for years. “These medications decrease the secretion of intrinsic factor, a protein secreted by stomach cells that is vital for transporting B12 from the stomach to the final part of the small intestine, where it is absorbed.” , explains Cohen.

People who have had stomach surgery to lose weight, older adults, and people with gastrointestinal illnesses like Crohn’s disease and celiac disease are also at risk for vitamin B12 deficiency, she says. .

Vitamin B12 deficiency symptoms

According to doctors, vitamin B12 deficiency has some characteristic symptoms:

“B12 is essential for energy production,” says Dr. Amit Sachdev, medical director of the department of neurology at Michigan State University. “The most common manifestation of vitamin B12 deficiency is fatigue.” This fatigue and associated symptoms can be confused with symptoms of depression and dementia, he says.

People with a vitamin B12 deficiency may exhibit forgetful and confused behavior, and have difficulty concentrating and completing tasks, Kaiser says. With more severe vitamin B12 deficiencies, a person may develop delusions and paranoia. “It could mimic dementia,” Kaiser says.

How to distinguish vitamin B12 deficiency from dementia symptoms

Doctors say it’s difficult to tell from a physical exam whether a person has a vitamin B12 deficiency or dementia. “There’s no way to tell the difference based on (cognitive) symptoms,” says Parul M Goyal, MD, assistant professor of medicine at Vanderbilt University Medical Center and director of Medicine for the Elderly at Vanderbilt One Hundred Oaks.

However, having gastrointestinal symptoms that started around the same time as cognitive problems may make a doctor suspect a vitamin B12 deficiency, says Sachdev. “The combination of bodily and cognitive changes is a major clue that a treatable cause such as vitamin B12 deficiency might be involved,” he says.

How vitamin B12 deficiency is detected

If a doctor suspects a vitamin B12 deficiency, he or she will usually order blood tests to check the patient’s levels, Kaiser says. But having lower levels of vitamin B12 doesn’t automatically mean a person’s symptoms are caused by a deficiency.

“Vitamin B12 deficiency is also more common in people with Alzheimer’s disease, so two things can happen,” says Kaiser. As a result, doctors will usually recommend taking a vitamin B12 supplement and seeing what happens. “If you treat vitamin B12 deficiency and the symptoms improve, it will help you know the cause,” says Kaiser.

But Sachdev says if your loved one has regular checkups with blood tests, things should never get to this point. “Routine laboratory monitoring of B12 during well checks is the most common way to detect a deficiency,” he says.

What to do if a loved one has dementia-like symptoms

If your loved one is showing signs of dementia, doctors stress it’s important to see a healthcare professional for an evaluation. “Many people will avoid having an evaluation because of common misconceptions that these memory changes are normal with age, but that is not a useful assumption,” says Kaiser. “There’s a misconception that we can’t do anything about it – that’s not true.”

Once you get an evaluation, a doctor will usually order a blood test to check for vitamin B12 deficiency, as well as other potential factors that could cause dementia-like symptoms, says Sachdev. If your loved one does indeed have a vitamin B12 deficiency, oral or intramuscular supplements will likely be prescribed, says Sachdev. If they’re taking a medication that could be causing the deficiency, such as a proton pump inhibitor or metformin, a doctor may recommend trying a different type of medication, says Goyal.

Ultimately, doctors emphasize that vitamin B12 deficiency and the resulting symptoms are reversible. “The effects of supplements are often noticed within a few weeks,” says Sachdev.

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This story was originally featured on Fortune.com