Watch your vitamins

Lack of vitamin B12 can interfere with the body’s production of red blood cells and lead to severe health problems


Vitamin B12, or colabin, is responsible for the proper functioning of the brain and nervous system. Photo: iStockphoto
Vitamin B12, or colabin, is responsible for the proper functioning of the brain and nervous system. Photo: iStockphoto

A Chennai-based homemaker, 42, had been suffering from chronic exhaustion for over a year. She felt a distinct weakness on the left side of her body. It gradually became worse, to a point where she could barely sling a purse over her left shoulder without pain. But it was the constant tingling alternating with numbness in her hands and feet, much like the pins and needles sensation, that finally drove her to see a physician. She mentioned that she faced difficulty walking, had trouble with balance, felt sluggish and weak. The doctor, after ruling out diabetes, sent her to a neurologist, because he suspected she had multiple sclerosis, a disease that affects the central nervous system. However, when the neurologist questioned her about her diet, he learnt she had turned vegan for health reasons (eliminating all dairy and animal products from her diet) just a year ago. He ordered a blood test, which confirmed a severe vitamin B12 deficiency.

She was given periodic B12 injections and later, daily B12 supplements were prescribed. Six months into the treatment, much of the feeling of lethargy and discomfort has been reversed.

Vitamin B12, or colabin, is responsible for the proper functioning of the brain and nervous system. Deficiencies, however, are commonplace.

A study published in 2011 in the International Journal Of Pharma And Bio Sciences observed that deficiencies were more common among the urban population and that women were at greater risk. Of the 422 people (of all ages) screened in Delhi, 12% were found deficient.

Why we need it

Vitamin B12 plays a critical role in the way our bodies function. “It is essential for proper red blood cell (RBC) formation and neural (nerve) functioning. It governs the transmission of signals in our nervous system,” says Manjari Tripathi, professor (neurology), All India Institute of Medical Sciences (Aiims), Delhi.

Vitamin B12 levels can be ascertained through a simple blood test that costs Rs1,500-2,000, yet it’s seldom a mandatory part of health check-ups either during pregnancy or as a matter of course. “It’s certainly one of the most misdiagnosed and under-treated conditions,” says Prof. Tripathi.

How deficiency occurs

B12 is absorbed by our bodies when we consume meat and animal-based products such as milk, cheese and eggs. Vegetarians and vegans who do not consume B12 supplements and eliminate meat and animal products entirely from their diets are at risk of deficiency. “The levels of B12 in our bodies should range from 200-900mcg (ideally above 400),” says Prof. Tripathi.

While non-vegetarians do get plenty of B12 with their intake of meat, they too can develop a deficiency if their bodies are unable to absorb the vitamin properly. That’s why regular monitoring and supplementation (if deficient) are necessary. “We require 2.4mcg of B12 a day,” says Manish Sinha, consultant neurologist at Alchemist Hospital in Panchkula, Chandigarh, and Nerve Care Centre, Delhi. “Deficiencies develop over a span of several years of continued deprivation,” he adds.

Dietary Sources

In a vegetarian diet, you can get B12 only from fermented foods, probiotic yogurt and yeast, says Prof. Tripathi. In a non-vegetarian diet, fish, seafood and poultry are rich sources. Of course, just consuming these foods won’t ensure that you get your daily supply.

“Several medical conditions can cause situations where your body won’t absorb B12 as effectively. If you self-medicate frequently with over-the-counter antacids, your stomach lining is at risk of damage, preventing absorption of B12 from the foods you eat,” says Prof. Tripathi. Bariatric surgery (often performed on obese patients to shrink their stomachs) can cripple the ability to absorb B12. Other factors can influence absorption too—old age, poor immunity and a lack of other crucial vitamins, such as folic acid and D, in the diet.

In fact, a 2015 study published in the Journal Of Family Medicine And Primary Care found that of the 100 patients with B12 deficiency surveyed, only 33% were vegetarian. The major cause of the deficiency in the others was low levels of folic acid, which hindered B12 absorption from foods.

Complications

If a B12 deficiency is left untreated, it can unleash a Pandora’s box of health complications.

“Lack of B12 can interfere with your body’s production of RBCs. Your RBCs are often immature in development and are bigger in appearance. This can leave you feeling exhausted and drained, a condition called pernicious anaemia,” says Dr Sinha. Pernicious anaemia is considered more severe than the regular, better-known anaemia caused by a lack of iron. This is because it leads to poor oxygen circulation, causing muscular pain, spasms and a build-up of chemicals that stimulate the nerves. It can also cause palpitations and breathlessness.

This, in turn, can lead to significant nerve damage. “Vitamin B12 protects the myelin sheath—the outer covering of the nerves—in the peripheral nervous system. When myelin is destroyed, nerve signals slow down. It’s accompanied by a burning, tingling feeling in the extremities—the hands and feet. A loss of sensation and numbness follow.” At this stage, supplements aren’t enough, especially if your doctor suspects problems with absorption of B12.

“Nerve damage must be treated with injections of B12 to ensure that it is being absorbed. We prescribe daily injections for a week and taper it to weekly doses for a month and monthly doses for a year,” says Prof. Tripathi.

Excessive B12 is not harmful—there are no proven side effects. Your body takes what it needs to repair the damage and stores the rest. “When treatment is given in the early stage, nerve damage can be entirely reversed. Even at a later stage, 80% of the damage can be repaired. That’s why it’s critical to catch this deficiency early,” adds Prof. Tripathi. Some patients may require physiotherapy.

Depression, fatigue, apathy, lack of concentration and panic attacks are all typical symptoms of a B12 deficiency, says V. Umamaheswari Vanamoorthy, consultant in neuropsychiatry and geriatric psychiatry at KG Hospitals and Nalavind Medical Centre, Coimbatore. “In the early stages, it can cause occasional memory lapse. When left untreated, it can even lead to dementia. However, when dementia is caused by a B12 deficiency, it can be reversed. That’s why all dementia patients (and the elderly) must take a blood test to ascertain their B12 levels and to see if their condition is reversible,” says Dr Vanamoorthy.

Research by the UK’s University of Warwick established that a B12 deficiency during pregnancy may predispose the child to metabolic problems such as type 2 diabetes. A study published in 2015 in the Journal Of Family Medicine And Family Care noted that B12 deficiency was often accompanied by a folic acid deficiency—another critical B vitamin vital for the developing baby. “For this reason, it is important for women to be tested for B12 deficiency during pregnancy,” says Sanjiv Agarwal, managing director-founder, Diabetacare, Bengaluru. “Women with B12 deficiency in early pregnancy were up to five times more likely to have a child with neural tube defects, such as spina bifida. Mothers with low B12 levels had a higher body mass index (BMI) and were more likely to give birth to babies with low birth weight as well as high cholesterol levels,” he says.

So, diagnosing vitamin B12 deficiency in time and providing effective treatment can limit the burden of disease and disability.

More From Livemint