Millions Face Undiagnosed Vitamin B-12 Deficiency, Experts Warn

Vitamin B-12 deficiency is a widespread yet often overlooked health issue. Recent studies indicate that around 6% of Americans under the age of 60 and nearly 20% of those over 60 suffer from this condition. The deficiency can stem from various factors, including dietary choices, medication use, and absorption issues, particularly prevalent in older adults.

Dr. Majid Fotuhi, a neurologist and adjunct professor at Johns Hopkins University, emphasizes the importance of addressing this deficiency, stating, “Vitamin B-12 deficiency is one of the few reversible causes of cognitive decline. Catching it early can prevent long-term brain damage and restore mental clarity.”

The Importance of Vitamin B-12 for Brain Health

Vitamin B-12 plays a critical role in maintaining brain health. It aids in the production and preservation of myelin, the protective sheath surrounding nerve fibers, ensuring efficient communication between brain cells. Moreover, it supports DNA synthesis and the health of brain tissue over time.

B-12 is also crucial for the production of neurotransmitters such as dopamine and serotonin, which are essential for regulating mood, focus, and motivation. Additionally, it helps the body break down homocysteine, an amino acid that can accumulate when B-12 levels are low. Elevated homocysteine is linked to increased oxidative stress and impaired blood vessel function, potentially exacerbating cognitive decline.

“Together, these roles make B-12 essential for sharp thinking, memory, and mental energy,” Fotuhi adds. When B-12 levels drop, nerve signals can slow or misfire, leaving brain cells more vulnerable to damage. Long-term deficiency can result in confusion, balance issues, slower cognitive processing, and concentration difficulties. Furthermore, research has associated high homocysteine levels with cognitive decline and neurodegenerative diseases, including Alzheimer’s disease and other forms of dementia.

Recognizing the Symptoms of Low B-12 Levels

The symptoms of a B-12 deficiency are varied and can manifest throughout the body. Common indicators include fatigue, weakness due to anemia, numbness or tingling in extremities, heart palpitations, memory issues, concentration difficulties, balance problems, and mood changes such as irritability and depression.

Anemia is frequently associated with B-12 deficiency, but neurological symptoms can occur even in the absence of anemia. According to Dr. Brian J. Copeland, a neurologist at University Medical Center New Orleans, “Symptoms of a B-12 deficiency may not appear until B-12 levels are significantly low in the body.”

Registered dietitian Patricia Kolesa notes that serum vitamin B-12 levels of 200 pg/ml or lower confirm a deficiency. Measuring homocysteine and methylmalonic acid can also provide insights into B-12 activity. Some older adults may display cognitive and neurological issues despite having B-12 levels within the normal range, albeit on the lower end.

If individuals are concerned about memory loss, fatigue, balance issues, or other related symptoms, consulting a healthcare professional for B-12 testing is advisable. “Vitamin B12 deficiency is common, underrecognized, and relatively easy to diagnose and treat,” states Dr. Joel Salinas, a clinical associate professor at the New York University Grossman School of Medicine. “Its neurological and cognitive effects can mimic more serious brain disorders, which is why it is routinely assessed in evaluations for cognitive decline.”

Who Is at Risk for Vitamin B-12 Deficiency?

Vitamin B-12 is essential for red blood cell production, and adequate dietary intake is necessary for maintaining healthy levels in the body. The absorption of B-12 requires a protein called intrinsic factor, produced by cells in the stomach. As the body cannot synthesize vitamin B-12, individuals who do not consume sufficient amounts through diet or supplements are at risk.

Vegetarians and vegans are particularly vulnerable, as B-12 is predominantly found in animal products. Individuals with gastrointestinal disorders that affect nutrient absorption, such as Crohn’s disease or celiac disease, those with pernicious anemia, a history of stomach or bariatric surgery, and heavy alcohol users may also face increased risk.

Older adults are more likely to experience B-12 deficiency due to decreased absorption with age. Additionally, long-term use of medications such as metformin and acid-suppressing drugs can contribute to low B-12 levels, as noted by Salinas.

Steps to Address Low B-12 Levels

Maintaining a diet rich in B-12 is vital for overall health. Good sources include fish, meat, eggs, dairy products, nutritional yeast, and fortified cereals. Those diagnosed with a deficiency may need B-12 supplements, either orally or through injections.

Basic blood panels conducted by primary care doctors can determine if an individual is deficient or has low vitamin B-12 levels. Salinas explains, “Oral B12 supplements are effective for most patients, while injectable forms are used in more severe cases. Blood testing is the most reliable way to determine whether dietary intake alone is adequate.”

Testing for B-12 deficiency is essential to prevent progression to irreversible levels. Early treatment can reverse memory loss, mood changes, and concentration problems. In contrast, untreated deficiencies may lead to permanent memory loss or even dementia, as highlighted by Copeland. “In the most severe forms, this can progress to frank dementia with behavioral symptoms including psychosis,” he warns.

This information underscores the importance of monitoring vitamin B-12 levels, particularly in individuals experiencing unexplained memory loss or cognitive decline.