A look into the role of Vitamin B12 and how to know if you’re deficient

Vitamin B₁₂ is a nutrient that’s essential for not only the making of DNA but also DNA repair, two process that are absolutely critical for your survival. To continue replicating, you need to keep manufacturing DNA and you also need to ensure that your DNA, which undergoes daily bombardment by a host of environmental and internal insults, is preserved in its pristine primordial form. Damaged DNA can seed abnormal cells, which can morph into cancers, an evolution that can unfold without setting off any undue warning signals. This is a development that can progress to a lethal presence when it’s too late to reverse what has already become cataclysmic.

Aside from nurturing and protecting DNA vitamin B12 also provides us with energy.

Aside from nurturing and protecting DNA, vitamin B₁₂ also stands at the epicentre of methylation, an essential biochemical process that provides us with energy, allows our livers to function and detoxify, impacts on the way our genes express themselves and drives our emotions and mental capacity. The clarity of our thoughts, how well we remember, our emotions, calmness, depression or anxiety all rely on the presence and activity of vitamin B₁₂. Rather than latch on to Prozac and Valium as panaceas for emotional distress, it might be more worthwhile assessing and optimising vitamin B₁₂ status to alleviate emotions that have become unhinged.

Vitamin B₁₂ also contributes to the formation of red blood cells, which carry oxygen around our bodies to our cells, which need this critical substance to produce energy and without which we would not be able to function. Our nerve cells are insulated by a protective covering called myelin, which is dependent on vitamin B₁₂.

The problem

The problem with B₁₂ is it can be sourced only from foods of animal origin. We cannot really obtain it in any meaningful way from vegetables, nor do we make it in sufficient quantities in our intestines. This means vegetarians and vegans are going to lack B₁₂. Then we need to produce adequate amounts of stomach acid and digestive enzymes to absorb B₁₂, functions that can be compromised in many of us and that also diminish as we age.

There’s a bunch of disorders that undermine B₁₂ absorption, including coeliac disease or gluten sensitivity, inflammatory diseases of the bowel, the presence of abnormal germs in the gut and autoimmune diseases whereby our immune systems attack molecules that are responsible for the absorption of this critical vitamin. Drugs called proton pump inhibitors that are used to treat indigestion and reflux by suppressing stomach acid can undermine B₁₂ status, as can a popular medication used to manage diabetes, called Metformin.

A host of antibiotics and the contraceptive pill can lower B₁₂ levels. Alcohol is also the enemy of B₁₂. There’s a number of genes that affect the way B₁₂ is absorbed and utilised and, with genetic testing becoming more sought-after by consumers and embraced by some practitioners, having a gene profile can provide useful information about B₁₂’s utility.

Deficiency

Given the multitude of reasons for not achieving the amount of B₁₂ we need to service its wide-ranging portfolio, it should come as no surprise that many of us are deficient. Fatigue, memory deficits, irritability, loss of concentration, pins and needles, numbness, unsteadiness and abnormal walking patterns, disorientation, shortness of breath, a smooth red tongue, insomnia and mouth ulcers are indicators that we aren’t getting enough B₁₂.

If you have any of these symptoms a blood test can confirm a B₁₂ deficiency and, while the normal range resides between 135 pmol/L and 650pmol/L, even conservative medical authorities recommend that optimal B₁₂ status sits above 350pmol/L. They go on to add that younger adults absorb 50 per cent of ingested B₁₂, while between 10 and 30 per cent of older patients may not be able to absorb adequate amounts from normal dietary sources. As a consequence, they suggest that patients older than 50 years should consume foods fortified with vitamin B₁₂ and take B₁₂ supplements.

Whether taking extra B₁₂ can prevent our brains from going into decline is still up for discussion. One thing B₁₂ does is allow your body to recycle homocysteine, a protein found in all of us, one of the initial reactions of the methylation cycle that is so vital for activating our genes, making energy, safeguarding DNA and facilitating all the other biochemical events that oversee our mental and emotional wellbeing. When homocysteine is high it can harm our brains and there’s some evidence that taking extra B₁₂ can lower homocysteine, but studies documenting that this actually preserves our mental function are conflicted, some showing benefits, others not.

What’s most concerning is whether taking supplementary B₁₂ can actually be harmful given the notion that many of us lack sufficient B₁₂. There are clinics where patients are administered extravagant amounts of this vitamin. Cancer cells need B₁₂ as much as our healthy cells do and, with studies linking high levels of B₁₂ to increased cancer risk, there’s the alarming possibility that taking extra B₁₂ might turn budding cancer cells into full-blown cancers, an event that would occur under the radar of medical surveillance. This possibility should give all those advocating excessive vitamin B₁₂ supplementation serious pause.