Tiredness That Won’t Go Away
Persistent fatigue is among the most reported symptoms of vitamin B12 deficiency, and it’s often overlooked. According to a 2024 study by the American Society of Hematology, over 65% of adults diagnosed with B12 deficiency reported chronic tiredness that didn’t improve with sleep. This type of tiredness is different from typical exhaustion because it lingers even after adequate rest and affects daily functioning. Experts suggest that B12 plays a key role in red blood cell formation, and without enough, less oxygen reaches your tissues, leading to fatigue. Foods rich in B12, such as fortified breakfast cereals, eggs, and dairy products, are recommended for vegetarians, while meat and fish remain top sources for omnivores. Newly published dietary guidelines in 2025 emphasize including at least two servings of B12-rich foods per day to combat this symptom. For plant-based eaters, nutritional yeast and fortified plant milks are practical alternatives.
Pale or Jaundiced Skin
Noticeable paleness or a subtle yellow hue to the skin is a red flag for B12 deficiency. In a 2024 report from the Mayo Clinic, dermatologists noted that pallor develops as red blood cell production declines, while jaundice results from increased breakdown of fragile red cells. This shift is most visible in the face and sometimes in the whites of the eyes. Experts at Johns Hopkins Medicine recommend routine blood tests for those with unexplained paleness, particularly older adults, since B12 deficiency incidence increases with age—affecting nearly 15% of adults over 60 in the United States as of 2024. To address this, consuming clams, salmon, and fortified tofu has been shown to support healthy skin tone by boosting B12 levels. Regular intake of these foods helps prevent the subtle but significant changes in complexion that come with deficiency.
Mouth Ulcers and a Swollen Tongue
Painful mouth ulcers and glossitis—a swollen, inflamed tongue—are increasingly recognized as signs of B12 deficiency. The British Journal of Nutrition highlighted in January 2025 that 28% of B12-deficient patients presented with oral symptoms before any blood changes were detected. These mouth issues can make eating and speaking uncomfortable, often leading to weight loss or poor nutrition. Dentists are now encouraged to screen for B12 deficiency in patients with recurring mouth sores. Foods like lean beef, Swiss cheese, and fortified nutritional yeast are recommended for quick dietary intervention. The latest guidelines from the World Health Organization advise adults to monitor for these oral signs, especially if following restrictive diets, and to add B12-fortified foods to daily meals to reverse symptoms.
Numbness and Tingling in Hands or Feet
Neurological symptoms, such as numbness, tingling, or a “pins and needles” sensation in the hands and feet, are now recognized as hallmark warning signs of B12 deficiency. A 2024 review from the National Institutes of Health reveals that 40% of undiagnosed B12-deficient individuals eventually experience these symptoms due to damage to nerve coverings. If left untreated, these issues can progress and become irreversible. Neurologists recommend early dietary changes for those at risk, suggesting increased consumption of shellfish, trout, and fortified plant-based milks. A case study published in Neurology Today (February 2025) demonstrated symptom reversal in patients who increased B12 intake through fortified foods and supplements. Regular B12 intake remains critical for nerve health, especially in populations over 50.
Shortness of Breath and Dizziness
Shortness of breath and unexplained dizziness are often tied to anemia caused by B12 deficiency. The Centers for Disease Control and Prevention (CDC) reported in March 2025 that nearly 10% of anemia cases in U.S. adults stemmed from low B12 levels, particularly among women and older adults. This occurs when the body cannot produce enough healthy red blood cells to carry oxygen efficiently. Cardiologists advise that individuals experiencing these symptoms, especially without clear cardiac or respiratory causes, should have their B12 levels checked. Increasing intake of sardines, beef liver, and fortified breakfast cereals has been linked to improved symptoms. The CDC now recommends routine B12 screening for anyone with persistent dizziness and breathlessness to enable early dietary correction.
Vision Problems
Blurry or disturbed vision, including double vision or seeing spots, can arise when B12 deficiency damages the optic nerve. A 2024 study published in Ophthalmology found that up to 5% of chronic B12-deficient patients reported visual changes, some of which were reversed with timely intervention. The mechanism involves impaired blood flow to the eye’s retina, leading to temporary or sometimes permanent vision loss. Eye specialists now counsel patients with unexplained vision issues to consider nutritional deficiencies, particularly in older adults or those on vegan diets. Incorporating foods like mackerel, fortified plant milks, and eggs can help restore B12 levels and protect eye health. Early detection and dietary changes are strongly encouraged to prevent progression.
Difficulty Walking or Balance Issues
Trouble with walking, balance, or frequent falls may indicate advanced B12 deficiency affecting the spinal cord. The American Academy of Neurology issued a 2025 advisory highlighting several recent cases in which older adults misattributed poor balance to aging, when it was actually caused by B12-related nerve damage. In these cases, dietary adjustments led to significant improvements within months. The Academy’s data shows that those over age 65 are most at risk, especially if they consume little animal protein. Adding more salmon, fortified soy products, and low-fat dairy can reduce risk and improve mobility. Doctors now recommend routine B12 assessments for anyone with new onset balance problems, regardless of age.
Mood Changes and Cognitive Decline
Irritability, depression, and memory problems are increasingly connected to B12 deficiency, especially among seniors. The Lancet Psychiatry reported in January 2025 that up to 22% of patients diagnosed with major depressive disorder had low B12 levels. Cognitive symptoms may include confusion, difficulty concentrating, and even early-onset dementia. Psychiatrists and geriatricians now routinely check B12 as part of mental health evaluations in older patients. Dietary strategies include more turkey, fortified nutritional yeast, and fish to help stabilize mood and cognition. The Alzheimer’s Association recommends adults over 55 monitor B12 intake closely, as deficiency may accelerate cognitive decline if left unaddressed.
Heart Palpitations
B12 deficiency can cause heart palpitations—an irregular, fast, or pounding heartbeat—due to its impact on the cardiovascular system. The American Heart Association released updated guidance in April 2024 warning that low B12 can mimic symptoms of heart disease, leading to unnecessary treatments. In clinical trials, nearly 12% of patients with palpitations were found to have B12 deficiency as a root cause. Cardiologists now stress getting B12 levels checked before starting cardiac medications, especially in younger adults without heart disease risk factors. Eating more tuna, eggs, and B12-fortified cereals can help regulate the heartbeat and reduce symptoms. The Heart Association also encourages regular dietary reviews for those experiencing unexplained palpitations.
