Vitamin B12 deficiency in men: What signs did my patient ignore till he collapsed?

Yet B12 is one of the most important vitamins that’s needed for DNA synthesis, brain function, maintaining healthy nerves and forming red blood cells. While the liver can store B12 for three to five years, deficiencies occur when intake or absorption fails. Humans must obtain B12 through diet (meat, fish, dairy) or supplements, as the body cannot create it.

Why men tend to ignore vitamin B12 deficiency

It started subtly. A tingling sensation in his toes. Occasional dizziness. Increasing forgetfulness. His family noticed mood swings and uncharacteristic irritability. “I thought I was just stressed,” he would later recall.

Men are least likely to get themselves tested for vitamin B12 deficiency compared to women because they do not consider it to be a serious health issue. They visit doctors less frequently, delay routine bloodwork and avoid reporting mood or cognitive symptoms. So, vitamin B12 deficiency can go undetected for years. Besides, they tend to attribute the obvious symptom of fatigue to stress, depression, low testosterone, diabetes, cholesterol, obesity and stress. Even doctors may check testosterone or glucose levels first — not B12.

What are signs and symptoms?

By the time my patient was admitted to hospital, he was struggling to walk in a straight line. He had difficulty recalling recent conversations. Blood tests revealed profound megaloblastic anaemia, a condition of enlarged, dysfunctional red blood cells associated with critically low B12 levels. An MRI scan confirmed what I had feared, early signs of subacute combined degeneration, a serious neurological complication where the spinal cord begins to deteriorate. Without B12, the nervous system literally starts malfunctioning.

In extreme cases, deficiency can lead to psychosis, paralysis, permanent nerve damage, sudden weight loss and very poor appetite. Alcohol use can further complicate matters by contributing to thiamine (vitamin B1) deficiency, increasing the risk of brain disorders. Sore tongue, mouth ulcers, reduced vibration and position sense, leading to poor balance, memory problems and brain fog, are fairly noticeable. Vitamin B12 levels lower than 100 can push up levels of homocysteine, a half broken down amino acid that can thicken the blood and form clots. Then patients could develop pernicious anaemia, an autoimmune condition that prevents your body from absorbing vitamin B12 and damaging the nervous system irreversibly if left untreated.

What about treatment?

I started my patient on high-dose injectable B12 and nutritional therapy. In severe deficiency cases, we recommend daily shots for a week, then taper it out to weekly and monthly jabs. A deficient person needs over four weeks to report normal blood counts.

His anaemia improved within weeks. His cognitive clarity slowly returned. But some nerve damage lingered as a consequence of delayed diagnosis.

Those at highest risk include strict vegans without supplementation, older adults with absorption issues, individuals with gastrointestinal disorders, and people with chronic alcohol dependence.

My patient’s story serves as a stark reminder that sometimes the most dangerous health threats are not dramatic illnesses, but silent deficiencies hiding in plain sight.

(Dr Tickoo is Director, Internal Medicine, Max Healthcare)