On World Vitamin B12 Awareness Day, we feature an exclusive interview with Prof. Dominic Harrington, Chief Scientific Officer at Synnovis and world-leading expert in this field. We delve into the importance of vitamin B12, how to accurately test for deficiencies, and why early detection is crucial.
Why is vitamin B12 important?
Vitamin B12 is an essential micronutrient that plays a crucial role in various bodily functions. It is vital for DNA synthesis, the production of red blood cells, and the functioning of the nervous system. Although we only need 2–3 μg of vitamin B12 each day, deficiency is common and has serious health implications if left untreated.
Vitamin B12 is only made by certain bacterial strains. Fermentation in the guts of herbivores helps the growth of these microorganisms and the B12 they make is incorporated into their tissues. Plants cannot make or store B12 which means we can only obtain B12 by eating animal-derived food such as meat, dairy, and eggs or by taking supplements. It is estimated that around 6% of people under the age of 60 and up to 20% of those over 60 are affected by B12 deficiency. Without adequate B12, individuals can develop anaemia, neurological issues, and neuropsychiatric disorders.
What could be signs and symptoms of a B12 deficiency?
The signs and symptoms of B12 deficiency vary considerably from person-to-person. Common symptoms include fatigue, weakness, constipation, loss of appetite, and weight loss. Neurological symptoms might include numbness and tingling in the hands and feet, difficulty maintaining balance, depression, confusion, dementia, and poor memory.
It's important to note that these symptoms can develop slowly and may be subtle at first – and that not all B12 deficient patients develop signs such as anaemia. B12 deficiency is often undiagnosed because its symptoms can be non-specific and overlap with other conditions. Studies suggest that B12 deficiency is frequently missed. This underscores the need for better diagnostic practices and increased awareness among both patients and healthcare providers.
Who is at risk of B12 deficiency?
Testing for B12 deficiency is particularly important for individuals at higher risk. This includes older adults, vegetarians and vegans, people with gastrointestinal disorders like pernicious anaemia, Crohn's disease or celiac disease, and those who have had gastrointestinal surgery. Additionally, individuals taking certain medications, such as proton pump inhibitors or metformin, should also consider testing.
How can B12 deficiency be tested accurately?
Traditionally, serum B12 assays have been used to evaluate B12 status, but they have limitations in sensitivity and specificity. More accurate testing involves a combination of biomarkers. For instance, measuring holotranscobalamin (active B12) and methylmalonic acid (MMA) levels can provide a clearer picture. Elevated MMA levels, in particular, are a strong indicator of B12 deficiency. Using a first- and second-line testing algorithm, as we do at Synnovis, helps to improve diagnostic accuracy.
How can a B12 deficiency be treated? Can B12 deficiency-related illnesses be cured?
Treatment for B12 deficiency typically involves dietary changes, oral supplements, or B12 injections, depending on the severity of the deficiency and the underlying cause. For some people, increasing dietary intake of B12-rich foods like meat, dairy, and fortified cereals can be effective. In more severe cases, or when absorption is an issue, B12 injections are essential.
Importantly, the treatment must be tailored to the needs of the patient. With appropriate treatment, many of the symptoms of B12 deficiency can be reversed, and related illnesses can be managed effectively.